TRICKLE-L: 199709XX
is the compilation of discussion during Sep 97
via AB4EL Web Digests @ SunSITE
Date: Wed, 03 Sep 1997 00:03:07 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 29 Aug 1997 to 2 Sep 1997
There is one message totalling 60 lines in this issue.
Topics of the day:
1. August '97 Archives/New emitter technology
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
----------------------------------------------------------------------
Date: Wed, 3 Sep 1997 04:24:14 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: August '97 Archives/New emitter technology
Fellow Trickle-L subscribers:
The August 1997 archives have been compiled and organized on the
Microirrigation Forum web site.
Issues discussed last month were [URL in brackets]:
-Aggressive Yellow-Green Algae [www.mif.org/aggyga.html]
-Drip tape design for Emission Uniformity [www.mif.org/tades.html]
-Does gypsum improve water holding capacity [www.mif.org/gypwat.html]
-Graphical software [www.mif.org/graph.html]
-Irrigation system evaluations [www.mif.org/syseval.html]
-Langelier Saturation Index [www.mif.org/langsat.html]
-Oil clogging problems in buried drip [www.mif.org/oil.html]
-USBR Water Measurement Manual [www.mif.org/usbr.html]
----------------
After reading an article in "International Water and Irrigation Review"
(Vol. 17, No.1 pp-20-23),
there seems to be a new technology for creating a better drip emitter on
the horizon, although the particular article left many questions in my mind
regarding the validity of such technology.
The article stated that the new emitter has a mechanical device (a modified
and variable moving labyrinth) which during low pressures, water flows
through a short version of the labyrinth and under high pressures, water
flows through longer versions of the labyrinth. The main reason for various
movement of the labyrinth was to maintain emitter output regardless of
operating pressure.
Not being a nano-emitter technology specialist, I understood the general
goal and generic concept of developing this emitter: It could lead to
longer distribution laterals and dramatically decrease the pressure buildup
time for a large system to create a rapidly balanced microirrigation
infrastructure.
The particular emitter is patented by Metzerplas-Lego and was engineered by
Amir Cohen. The article stated that tests were performed at the 'Technion'
in Israel using water of various qualities (sewage, river water with algae,
flood water), and subjected emitters to variable topographies and laterals
of variable length. However, not too many specs (numbers/statistics) were
presented in the article and it made me wonder how authentic this
information was (sorry for being so objective).
Anyone out there have any more details regarding this new emitter device
patented by Metzerplas-Lego? Another question: The article referred to
button or cylindrical drippers as A.D.I.
What is A.D.I.?
Richard Mead
Trickle-L owner/manager
www.mif.org
------------------------------
End of TRICKLE-L Digest - 29 Aug 1997 to 2 Sep 1997
***************************************************
Date: Thu, 04 Sep 1997 00:03:40 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 2 Sep 1997 to 3 Sep 1997
There are 4 messages totalling 145 lines in this issue.
Topics of the day:
1. Software/hardware for using PC as data logger. (3)
2. MIF update
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
----------------------------------------------------------------------
Date: Wed, 3 Sep 1997 11:35:05 -0700
From: "Alan S. Wicks" (awicks@TELEVAR.COM)
Subject: Software/hardware for using PC as data logger.
Greetings,
Many years ago I used an Apple IIe as a data logger using some software
and hardware from a company called ADALAB back in Pennsylvania. Does
anyone know where I might find info on this type of software/hardware
for use on a PC so I can use an old 386 as a data logger? DOS or
Windows programs are of interest.
Thanks,
Alan S. Wicks
Kennewick, WA
------------------------------
Date: Wed, 3 Sep 1997 23:52:00 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: MIF update
Dear Trickle-L web surfers,
Yesterday I made an announcement regarding placement of the August archives
on the Microirrigation Forum web site. At the moment,[September 3 at 11:45
am my time], the www.mif.org URL is not functioning, yet the DNS number does.
Hence, if you want to refer to MIF during this, please use "209.36.115.150"
instead of "www.mif.org" (excluding quotes).
I will investigate this problem some time today. Thanks for your patience!
Richard Mead
Trickle-L owner/manager
http://209.36.115.150
------------------------------
Date: Wed, 3 Sep 1997 17:07:08 -0500
From: Joe Poirier (poirier@ACCN.ORG)
Subject: Re: Software/hardware for using PC as data logger.
Alan, I just received a copy of the September issure of Test and =
Measurement World. On page 13 there is an article on using Office97 =
(the Excel97 part of it) to control analog and digital I/O ports. It =
includes the schematic diagram for a circuit and the address to obtain =
the necessary software to communicate with the circuit through the =
parallel port on a PC. I have not tried this set-up and am not an =
expert on this type of data acquisition and control. But it looks like =
a fairly easy way to record analog data. If you know someone who is =
into electronics you could ask them to build that circuit for you. I =
have heard of other people writing macro's (control programs) in Excel =
Basic to get data into an Excel spreadsheet. So I don't think you would =
have to have Excel97. An older version of Excel would probably work. =
If you cannot get a copy of Test and Measurement World I could fax you =
the pages if you send me your fax number. I also have another source =
that supplies inexpensive circuits and software for data acquisition and =
control. I cannot find it now but I could also fax those things when I =
find them. JP
----------
From: Alan S. Wicks [SMTP:awicks@TELEVAR.COM]
Sent: Wednesday, September 03, 1997 1:35 PM
To: TRICKLE-L@crcvms.unl.edu
Subject: Software/hardware for using PC as data logger.
Greetings,
Many years ago I used an Apple IIe as a data logger using some software
and hardware from a company called ADALAB back in Pennsylvania. Does
anyone know where I might find info on this type of software/hardware
for use on a PC so I can use an old 386 as a data logger? DOS or
Windows programs are of interest.
Thanks,
Alan S. Wicks
Kennewick, WA
Attention list subscribers! Please DO NOT send any attached files =
(graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
------------------------------
Date: Wed, 3 Sep 1997 19:03:44 -0700
From: Marty Grogan (ges@OWT.COM)
Subject: Re: Software/hardware for using PC as data logger.
)Greetings,
)
)Many years ago I used an Apple IIe as a data logger using some software
)and hardware from a company called ADALAB back in Pennsylvania. Does
)anyone know where I might find info on this type of software/hardware
)for use on a PC so I can use an old 386 as a data logger? DOS or
)Windows programs are of interest.
)
)Thanks,
)
)Alan S. Wicks
)Kennewick, WA
)
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
)
)
Most Data Acquisition boards have rudimentary software with them. I have
used Quick Basic on occassion. See "Personal Engineering" magazine for many
sources.
M. G.
Marty Grogan, BSAE, MSEE
Owner, Grogan Engineering Services
1320 Adair Drive
Richland, WA 99352
(509)627-3083 (voice and FAX)
ges@oneworld.owt.com
Specializing in Electronics Based Products and Services for Precision
Agriculture: Research, Instrumentation, Data Systems, Telemetry and Remote
Sensing.
GES--The technology buckstopper.
(Detailed Resume Available: http://www.owt.com/users/ges/resume.html)
------------------------------
End of TRICKLE-L Digest - 2 Sep 1997 to 3 Sep 1997
**************************************************
Date: Fri, 05 Sep 1997 00:03:30 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 3 Sep 1997 to 4 Sep 1997
There are 7 messages totalling 259 lines in this issue.
Topics of the day:
1. Porous pipe made from recycled tires (4)
2. Porous pipe (Comments from F Lamm)
3. porous hose
4. August '97 Archives/New emitter technology
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
----------------------------------------------------------------------
Date: Thu, 4 Sep 1997 10:25:43 -0400
From: Larry Duane Geohring (ldg5@CORNELL.EDU)
Subject: Porous pipe made from recycled tires
Trickle Members,
Can anyone fill me in on the use of recycled and ground tires being used to
make porous pipe for subirrigation. It's my understanding that this type
of pipe is being buried 1 meter deep and being used in subirrigation.
Who makes this? Where is it sold? How much does it cost? What is the
performance experience with it?
Any info would be greatly appreciated.
Larry
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
++++++
Larry D. Geohring, Sr. Extension Associate
Department of Agricultural and Biological Engineering
212 Riley Robb
Cornell University
Ithaca, NY 14853
ph. 607-255-2481, FAX 607-255-4080, e-mail ) ldg5@cornell.edu
======
------------------------------
Date: Thu, 4 Sep 1997 16:15:43 -0500
From: "W. Bryan Smith" (wsmth@CLEMSON.EDU)
Subject: Re: Porous pipe made from recycled tires
) Can anyone fill me in on the use of recycled and ground tires being used to
) make porous pipe for subirrigation. It's my understanding that this type
) of pipe is being buried 1 meter deep and being used in subirrigation.
)
) Who makes this? Where is it sold? How much does it cost? What is the
) performance experience with it?
)
) Any info would be greatly appreciated.
)
) Larry
Larry,
I was told that a product called Leaky Pipe used to make this
claim some years ago ( I think around 1991 or so). At that time
they had offices in California and sold throughout the US. I
never had any experience with them, but was told it was a
porous-pipe type product of approximately garden hose size.
The fellow I talked with was a brand-new dealer and claimed it
had been used successfully on agricutural row crops, but had no info
on how long it had been buried, what the uniformity was, etc.
Hope this gets you started.
Bryan
=|===|===|===|===|===|===|===|===|===|===|=
W. Bryan Smith
Area Extension Agent - Irrigation / Water Quality
Clemson Extension Service
P.O. Box 160, Newberry, South Carolina 29108 USA
Office: 803 276-1091 FAX: 803 276-1095
Internet: wsmth@clemson.edu
=|===|===|===|===|===|===|===|===|===|===|=
All opinions are my own and not reflective of the
policies of Clemson University or the Cooperative
Extension Service.
------------------------------
Date: Thu, 4 Sep 1997 16:42:44 -0400
From: George Kunkel (gkunkel@CRIS.COM)
Subject: Re: Porous pipe made from recycled tires
At 10:25 AM 9/4/97 -0400, you wrote:
)Trickle Members,
)
)Can anyone fill me in on the use of recycled and ground tires being used to
)make porous pipe for subirrigation. It's my understanding that this type
)of pipe is being buried 1 meter deep and being used in subirrigation.
)
)Who makes this? Where is it sold? How much does it cost? What is the
)performance experience with it?
)
)Any info would be greatly appreciated.
)
)Larry
)++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
)++++++
)Larry D. Geohring, Sr. Extension Associate
)Department of Agricultural and Biological Engineering
)212 Riley Robb
)Cornell University
)Ithaca, NY 14853
)
)ph. 607-255-2481, FAX 607-255-4080, e-mail ) ldg5@cornell.edu
)
)============================================================================
)======
)
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
)
)I have used the "leaky pipe". It's readily available in hardware stores. I
had hoped it would be more permanent than conventional plastic drip,which
it is, but __any silt that gets through your filter will too quickly plug
it up so that water distribution becomes unpredictable. For this reason I
no longer use it at all. George Kunkel
)
------------------------------
Date: Thu, 4 Sep 1997 17:56:01 -0400
From: Tim1Utah@AOL.COM
Subject: Re: Porous pipe made from recycled tires
CIT at CA st. Univ., Fresno has done extensive testing of this product. you
might call them for information 209-278-2066 Tim W.
------------------------------
Date: Thu, 4 Sep 1997 17:38:47 -0500
From: Freddie Lamm (FLamm@OZNET.KSU.EDU)
Subject: Porous pipe (Comments from F Lamm)
In my estimation this stuff would be better suited for small
landscapes systems and gardens and situations where the water supply
can vary to match varying capacities. There are typically larger
variations in manufacturing in these products and some evidence of
performance changes with time (curing or hardening of rubber???). The
hydraulic pathways are also fairly small which can lead to easier
plugging.
Neither application fits typical agriculture where there are large fields with a finite
water pumping system to match a irrigation system hooked to it.
There are some ASAE papers by Allen Smajstrla and Ron Yoder which
discuss porous pipe or it's other names. Yoder's paper is in 5th
Microirrigation Congress proceeding and I believe Smajstrla's was at
1994 Winter ASAE Meeting in Atlanta .
If there is a realistic ag setting, I'd be happy to be informed.
Freddie
-------------------------------------------------------------------
Freddie Lamm *
Research Agricultural Engineer *** o
KSU Northwest Research-Extension Center ***** /|\
105 Experiment Farm Road *******\\
Colby, Kansas 67701-1697 *********
Ph. 913-462-6281 ***********
FAX 913-462-2315 *************
Email:flamm@oznet.ksu.edu It's all downhill from here.
------ THERE'S NO DOMAIN LIKE OZ, THERE'S NO DOMAIN LIKE OZ. ------
------------------------------
Date: Fri, 5 Sep 1997 00:37:14 +0000
From: "Frank Pacosa, M.S., PA 734 X3218" (PACOSAFR@KPNWOA.MTS.KPNW.ORG)
Subject: porous hose
"I'd like to hear about ag uses of recycled tire hose"
I have a small 1/4 acre organic raspberry farm in Cascade mtns of
washington. Top 12 inches porous sandy loam, old forest floor with
volcanic ash and landslide material. I use a recycled 3/4 inch porous
black hose bought at COSTCO My rows are 100 foot lengths spliced where
needed of a black tire recycled material.
I have well water at 60-80 lbs. pressure. Initial problems were plugging
with sand and a blue algae. These problems seemed to be resolved when I
upped my pump pressure, limited my lengths to no more than 100 ft, and
no more than 3x100 lengths per spigot from 1" pipe direct to pressure
tank. My sand plugging seems to have disappeared since I have
"developed" my well by pumping a lot of water over the last three years.
We had 5 weeks of no rain this summer I ran the porous hose on
alternating rows for 24hrs at a time every 2-3 day and added some hand
flooding to particularly dry areas about once a week.
None of my berries had white spots indicative of drought. (It rained
profusely the last week of august and I lost 80% of my crop to
botrytis)
I am expanding my fields to 1+ acres and intend to use the hose. At $9
per 80 foot length it is the only cost effective method I have seen.
If there is something less expensive let me know. My berries are far
superior to anything I've seen grown in the Pacific Northwest if I could
only solve some of the other environmental problems like root rot from
90inches of rain a year mostly in the winter. Hope I'm not to wordy.
Wind River Berry Farm Frank Pacosa 503 698 2515
Pacosafr@kpnwoa.mts.kpnw.org
------------------------------
Date: Thu, 4 Sep 1997 18:15:58 -0700
From: Rodney Ruskin (geoflow1@SLIP.NET)
Subject: Re: August '97 Archives/New emitter technology
)After reading an article in "International Water and Irrigation Review"
)(Vol. 17, No.1 pp-20-23),
)there seems to be a new technology for creating a better drip emitter on
)the horizon, although the particular article left many questions in my mind
)regarding the validity of such technology.
)
)The article stated that the new emitter has a mechanical device (a modified
)and variable moving labyrinth) which during low pressures, water flows
)through a short version of the labyrinth and under high pressures, water
)flows through longer versions of the labyrinth. The main reason for various
)movement of the labyrinth was to maintain emitter output regardless of
)operating pressure.
)
)Not being a nano-emitter technology specialist, I understood the general
)goal and generic concept of developing this emitter: It could lead to
)longer distribution laterals and dramatically decrease the pressure buildup
)time for a large system to create a rapidly balanced microirrigation
)infrastructure.
)
)The particular emitter is patented by Metzerplas-Lego and was engineered by
)Amir Cohen. The article stated that tests were performed at the 'Technion'
)in Israel using water of various qualities (sewage, river water with algae,
)flood water), and subjected emitters to variable topographies and laterals
)of variable length. However, not too many specs (numbers/statistics) were
)presented in the article and it made me wonder how authentic this
)information was (sorry for being so objective).
)
)Anyone out there have any more details regarding this new emitter device
)patented by Metzerplas-Lego? Another question: The article referred to
)button or cylindrical drippers as A.D.I.
)What is A.D.I.?
)
I know this dripper quite well - they use ROOTGUARD in it.
They have two drippers - one in-pipe, the other on-pipe - I have no idea why
they chose names like A.D.I. The technology appears to be valid. I have no
doubt that it is better than a diaphragm against a slit (e.g. Agrifim Agri+
or Netafim Ram), but it may not be better than a diaphragm against a
key-hole (e.g. Drip In P/C). I also would like to see more hard numbers and
more reliable objective tests for plugging resistance. This is difficult due
to the many different ways that plugging occurs so manufacturers select
conditions to favor their product.
Rodney Ruskin
rr@geoflow.com
)
------------------------------
End of TRICKLE-L Digest - 3 Sep 1997 to 4 Sep 1997
**************************************************
Date: Sat, 06 Sep 1997 00:02:19 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 4 Sep 1997 to 5 Sep 1997
There are 5 messages totalling 236 lines in this issue.
Topics of the day:
1. Introduction of new subscriber
2. porous hose (3)
3. Ag uses of porous hose (F Lamm comment II)
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Fri, 5 Sep 1997 07:19:45 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: Introduction of new subscriber
Here is an introduction of Nawee Jiracheewee from Thailand.
Welcome Nawee!
------------------------------------------------------------------------------
Thank you for giving me information about the Trickle-L and
adding me into the list. I would like to post brief introduction:
1. Briefly, what is your affiliation with drip irrigation?
) I work for the Dept. of Agriculture, Thailand and my job deals with the
use of micro-irrigation (mini-sprinkler and drip systems).
2. What crops or plants do you use drip irrigation on?
) Tropical fruits (Durain, Lichee, Longan), and landscape.
3. If using subsurface drip irrigation, what is the average depth of
placement of the drip lateral?
) I am planning to conduct a pilot-scale experiment on the use of SDI with
treated effluent. The placement of emitter will be approximately 25 cm
for maize. I have an experience on SDI for grape vine in Israel, there is
no significant difference of the yield between the placement of 25 cm and
40 cm.
4. What problems have you encountered with drip irrigation?
)emitter clogging, uneven water distribution when using too long lateral.
5. Fertigation is a real advantage of drip irrigation. What form of N, P
and K have you been trying and to what success?
) Fertilizers were applied manually. Only the method of irrigation has
been changed from the use of 2 inch-PVC hose (labor).I agree that
fertigation is more efficient when using drip irrigation.
6. Have you experinced a reduction in fertilizer and/or water use?
) I used to compare drip system with conventional method (PVC hose). Drip
irrigation applies water twice a week at the rate of 50-60 L/day, while
conventional method applies water approximately 140-200 L/day (once a
week).
7. Do you have water quality problem? If so, how do you tackle the
situation?
) The problem is not so serious, but sometimes the accumulation of
suspened soild can cause clogging. Normally, I use online emitter with
microtube extension attached on the stake so that drop of water can be
observed easily. Of course, filter system is cleand every irrigation.
8. How frequent do you irrigate?
)Several hours, twice a week.
9. Do you have rodent damage? If so, how do you control the problem?
) Very often, lateral lines are cut by knife or blade of mower when
weeding. I bury the lateral and keep only the microtube extention and
emitter above the ground.
10. Are you pleased with the uniformity of your systems? Were they
designed correctly.?
)Yes, when the emitter is clogged, it is cleaned or replaced. Once I used
too long lateral, the distribution of water along the lateral was
uneven. This problem was already solved.
11. How did you find out about the Trickle-L mailing list?
)I was introduced by a member of the list.
Thank you.
Nawee Jiracheewee
Dept. of agriculture, and Water Engineering and Management Program,
Agric. Engineering Div. School of Civil Engineering,
Chatuchak, Bangkok 10900, Asian Institute of technology,
Thailand Klong Luang, Pathumthani 10120, Thailand
Tel: 66--5798519 Tel: 66-2-5245795
FAX: 66-2-9405791 FAX: 66-2-5162126
------------------------------
Date: Fri, 5 Sep 1997 11:22:11 -0600
From: Gary Clark (GCLARK@FALCON.AGE.KSU.EDU)
Subject: Re: porous hose
Dear Mr. Pacosa,
Nice can of worms that you just opened. Regarding the porous hose:
Please check on the hydraulic properties (e.g. gpm per foot) at
different pressures,
How stable are the flow characteristics with time and distance
along the length of hose?
How uniform is the discharge of water with time and distance
(length)?
Other drip products are available and I am sure that these will be
posted very soon. Others and myself have worked with ground rubber
porous hose products and have found most to be very nonuniform, they
have varying discharge rates along the length of hose and at certain
locations the flow varies with time even with good pressure
regulation.
Basically, I would encourage you to investigate the water discharge
properties of the product very thoroughly.
G. Clark
*********************************************
Gary A. Clark, Ph.D., P.E.
Professor
Biological and Agricultural Engineering
147 Seaton Hall
Kansas State University
Manhattan, KS 66506-2906
Tel: 913-532-5580; Fax: 913-532-5825
*
*** Management Is The Key To Conservation ***
*
*********************************************
------------------------------
Date: Fri, 5 Sep 1997 13:38:08 -0400
From: "Craig A. Storlie" (storlie@AESOP.RUTGERS.EDU)
Subject: Re: porous hose
Porous Pipe - Tire Mire?
I didn't know porous pipe could be purchased so cheaply ($9/80 ft =
$0.11/ft). That is substantially cheaper than some of the industry's
top-shelf products but 2-3 times the cost of products that are being
used in ag for subsurface drip irrigation.
The others are right about the uniformity issues. For a GAIA 3/8" ID
porous hose, CIT reported a CV of 0.481, a discharge exponent of 1.14,
and Design Emission Uniformities ranging from 36-39% (all for pressures
ranging from 1-7 psi). In comparison to other drip products, these
values are poor.
However, porous hose certainly gets a lot of attention! BUT WHY? Is
it ease of use (P regulation, filtering, fittings), cost, longevity, or
just good marketing? I would appreciate hearing reasons from the list.
Craig Storlie
Extension Specialist in Agricultural Engineering
Rutgers University
------------------------------
Date: Fri, 5 Sep 1997 14:03:03 -0500
From: Freddie Lamm (FLamm@OZNET.KSU.EDU)
Subject: Ag uses of porous hose (F Lamm comment II)
Frank said (edited for brevity):
I have a small 1/4 acre organic raspberry farm in Cascade mtns of
washington. My rows are 100 foot lengths spliced where
needed of a black tire recycled material.
I have well water at 60-80 lbs. pressure. Initial problems were plugging
with sand and a blue algae. These problems seemed to be resolved when I
upped my pump pressure, limited my lengths to no more than 100 ft, and
no more than 3x100 lengths per spigot from 1" pipe direct to pressure
tank.
Freddie replied:
This ag use satisfied the two cases I said in my earlier remarks,
short rows and small systems; and a water supply that can handle
variation in water capacity of material. Your relatively high water
pressure when connected to the water tank can handle variation in
water flow from one lot of material to the next, since the system is
small. However on larger system blocks a few percentage points of
flow variation multiplied by a large number of acres would make pump
sizing a nightmare and you still would have the potential problem of
changes in the performance of the material with time (hardening or
curing of rubber). Perhaps you discard the material every year, but
I am not sure that upping the pump pressure could be a long term fix.
It would appear to me the plugging would still be occurring and
eventually would overcome your upped pressure. Maybe you replace
hose before that time.
Frank said:
....... and added some hand flooding to particularly dry areas about once a week.
Freddie replied: No way for me to know definitively but those dry
areas could be indicative of flow variation in the hose.
Frank said:
At $9 per 80 foot length it is the only cost effective method I have seen.
If there is something less expensive let me know.
Freddie replied: At 11.25 cents/ft there might be cheaper
alternatives or at least ones that might require a lower operating
pressure. The drip tape products in general would be considerably
cheaper and would use a much lower operating pressure. The hard
hose type products with inline emitters **might** be very similar in
cost and would use a lower operating pressure. These products would
generally have a lower coefficient of variation, because their
manufacturing process are much different.
Freddie commented: I noticed you did not indicate the flow capacity
of the material. That often tends to be the case with the porous
pipe type products. The flow capacity is loosely defined or may not
even be stated. Once again that's what make it most questionable to use
in design of larger agricultural systems where a pumping system must
provide the water directly to it without the aid of a pressure tank
or water tower (municipal settings)
Freddie
*.
-------------------------------------------------------------------
Freddie Lamm *
Research Agricultural Engineer *** o
KSU Northwest Research-Extension Center ***** /|\
105 Experiment Farm Road *******\\
Colby, Kansas 67701-1697 *********
Ph. 913-462-6281 ***********
FAX 913-462-2315 *************
Email:flamm@oznet.ksu.edu It's all downhill from here.
------ THERE'S NO DOMAIN LIKE OZ, THERE'S NO DOMAIN LIKE OZ. ------
------------------------------
Date: Fri, 5 Sep 1997 16:24:44 -0400
From: Loren Welch (LWelch5168@AOL.COM)
Subject: Re: porous hose
Gary...happy to see you are weighing in on the porous pipe questions.....you
know about the applications of porous pipe vs other products. Thanks
Frosty
------------------------------
End of TRICKLE-L Digest - 4 Sep 1997 to 5 Sep 1997
**************************************************
Date: Sun, 07 Sep 1997 00:03:14 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 5 Sep 1997 to 6 Sep 1997
There is one message totalling 30 lines in this issue.
Topics of the day:
1. Fw: irrigation management software program
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Sat, 6 Sep 1980 16:59:42 -0700
From: "Aron A. Quist" (stanworth@MAIL.TELIS.ORG)
Subject: Fw: irrigation management software program
Does anyone know of a good, simple irrigaiton management software program
for scheduling irrigaitons for crops based upon the "feel" method? I
have
seen Roy, but I believe it may be too user unfriendly.
I am a consultant using this method in the desert south west on primarily
agronomic crops in basin or furrow irrigated fields. Right now I am
using paper, pencil, calculator and Cimis info.
I know this does not pertain directly to drip irrigaiton, but I could
use
some suggestions, comments or referals.
Thanks,
Aron
Aron A. Quist, CPAg/SS
Stanworth Crop Consultants, Inc.
Blythe California
stanworth@mail.telis.org
------------------------------
End of TRICKLE-L Digest - 5 Sep 1997 to 6 Sep 1997
**************************************************
Date: Tue, 09 Sep 1997 00:01:11 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 6 Sep 1997 to 8 Sep 1997
There are 2 messages totalling 131 lines in this issue.
Topics of the day:
1. Fw: irrigation management software program
2. ALUMINUM TOXICITY 1
##############################################################
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or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Mon, 8 Sep 1997 09:11:47 -0400
From: Fedro Zazueta (fsz@GNV.IFAS.UFL.EDU)
Subject: Re: Fw: irrigation management software program
At 04:59 PM 9/6/80 -0700, you wrote:
)Does anyone know of a good, simple irrigaiton management software program
)for scheduling irrigaitons for crops based upon the "feel" method?
Aron,
In a newly developed CDROM on citrus, there is a some scheduling software
available. The software was written specifically for citrus but can be used
for any microirrigated crop.
If you are interested in more details please contact me per the email below.
Fedro S. Zazueta, Director
IFAS Information Technologies Office
IFAS, Bldg. 162
University of Florida
Gainesville, FL 32611
Tel: 352-392-3196
FAX: 352-392-3520
Email:fsz@gnv.ifas.ufl.edu
Web: www.agen.ufl.edu/~fzazueta/
------------------------------
Date: Sun, 7 Sep 1997 20:02:18 -0400
From: Frank Hartman (suemc@GATE.NET)
Subject: ALUMINUM TOXICITY 1
ALUMINUM TOXICITY IN AGRICULTURE- How it works and how to reverse it;
implications in irrigation.
The fact that aluminum is toxic to living arganisms is well documented.
What has not been understood is the method of action and how to reverse
it.
The ability of any aqueous solution including water, blood and urine to
carry material in suspension without settling out is a function of a
minute, electrical charge on small particles in the solution.
These particles (colloids) are usually one micron or less in size and
not visible to the naked eye. As long as the particles carry an negative
charge of -20 millivolts (Mv) or greater, the solution is stable.
Aluminum is a trivalent cation (three positive electrons) which
destroys the electronegative charge on the particles in suspension.A
substance with three posive electrons has 6000 times more effect on
suspension stability than a substance with one positive electron making
aluminum very destructive of
supension stability..
As the negative charge on particles is reduced, the small particles
begin to clump together and either settle out or look for a receptor
with the appropriate charge to attach themselves. Scale in pipes.is a
classic example of the principle at work as is biofilm corrosion in
pipes and condensers. Algae and biofilms are caused by the same
mechanism. Any air conditioner with an aluminum drip pan will have a
problem with algae growth in the discharge line though few realize it is
the aluminum that causes it.
When the abiltiy of the water.to carry material in solution is
destroyed, plants are being fed by water that has almost the same
characteristics as distilled water.The water is unable to carry
nutrients into the plant and disease will flourish not only from
undernourished plants but also from the clumping of other materials in
suspension.Many potenially toxic materials are handled in living systems
without a problem as small colloids and may even contribute to the
vitality of the system. When the charge on the entire system drops below
about -10mv., they become toxic to the system.
Implications is agriculture.
There are several other principles that affect suspension stability
that are germane to irrigation.
1. Lowering the pH, lowers the electronegative charge. Aeration lowers
the pH due to the ineraction with atmospheric carbon dioxide (0.03%)
2. Depth of the water in the reservoir has an effect as the top one
third will contain about 0.03 carbon dioxide;below thirty feet carbon
dioxide may be as high as as 40-50 ppm..
3. Electromagnetic radiation, 60 cycle AC, as from a motor on a
pump reduces the charge.
4. Any colloidal system can be "salted out" by the addition of too
much salt regardless of the source.
Reversal
The obvious solutions of eliminating salt and aluminum are not, at
present, practical. Whats works is this;
1.. For normal irrigation, there are devices which impart a high
electronegative charge on water and cause about a 20% drop in surface
tension. The effect of the reduction in surface tension is the water
will dissolve more nutrients from the soil and carry them to the
plant.(.System cost about $3000.00
with almost no maintainence; uses about seven cents of electricity per
day.)
2. Coupled with the above, the addition of a small amount of
eitherof two mineralized rock dusts
in small quantities into the water will stabilze the colloidal solution.
(Cost less than $100.00 for most systems) Also a trivalent anion like
potassium citrate can be added which has three negative ions.
3. In severe salted out situations, there is a product used in
oilfield remediation which may be necessary.
Information for products for particular applications is available from
esystems@flash.net or from the author.
This is a over-simplification of the whole area of colloidal chemistry
dealing with this subject which is little understoood. Most of the more
recent texts deal with the more esoteric aspects of Zeta potential,
surface charge and colloidal chemistry rather than what I call practical
Zeta Potential.
For those interested in a better understanding the following are
recommended:
1. Zeta Potential- the complete course in 5 minutes available from Zeta
Meter- fax 540 886-3728; sales@zetameter.com.
2.Intoduction to Colloidal Chemistry-Mysels-Wiley/Interscience 1959
edition
3.Control of Colloidal Stabilty through Zeta Potential - Thomas
Riddick.available on interlibrary loan
as it is out of print.
C 1997 Frank H._
.
------------------------------
End of TRICKLE-L Digest - 6 Sep 1997 to 8 Sep 1997
**************************************************
Date: Wed, 10 Sep 1997 00:01:53 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 8 Sep 1997 to 9 Sep 1997
There are 10 messages totalling 505 lines in this issue.
Topics of the day:
1. (Fwd) (Fwd) VIRUS WARNING (2)
2. ALUMINUM TOXICITY 1 (2)
3. New emitter technology
4. Porous pipe made from recycled tires
5. ALUMINUM TOXICITY: The debate continues (2)
6. Water treatments
7. Re PENPAL virus Another hoax
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Tue, 9 Sep 1997 09:18:22 +0000
From: Adriaan van Niekerk (IRRI7@ING1.AGRIC.ZA)
Subject: (Fwd) (Fwd) VIRUS WARNING
------- Forwarded Message Follows -------
From: "Anelda Dorfling" (ING1/DATA5)
To: #everyone
Date: Tue, 9 Sep 1997 08:45:18 GMT-2
Subject: (Fwd) VIRUS WARNING
ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
Name: Adriaan van Niekerk
Company: Institute for Agricultural Engineering (ARC)
Address: Private Bag X 519
Silverton
South Africa
0127
Telephone: International: 02712 842 4037
Local: 012 842 4037
Fax: International: 02712 804 0753
Local: 012 804 0753
E-mail: irri7@ing1.agric.za
ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
------------------------------
Date: Tue, 9 Sep 1997 15:11:05 +0000
From: Adriaan van Niekerk (IRRI7@ING1.AGRIC.ZA)
Subject: (Fwd) (Fwd) VIRUS WARNING
Bryan,
Thank you for letting me know that the message did not came through
completly. My apology to the group!!
I wil try once more. I think I know what the problem was and I have
hopefully corrected it. Here goes!
------- Forwarded Message Follows -------
From: "Anelda Dorfling" (ING1/DATA5)
To: #everyone
Date: Tue, 9 Sep 1997 08:45:18 GMT-2
Subject: (Fwd) VIRUS WARNING
------- Forwarded Message Follows -------
) IMPORTANT!!!!
))
)) A few hours ago, Someone opened an E-mail that had the subject
)) heading of ao4free.com
))
)) Within seconds of opening it, a window appeared and began to
)) display all files that were being deleted. The user immediately
)) shut down the computer, but it was too late.
))
)) This virus wiped all out. It ate the Anti-Virus Software that
)) comes with the Windows '95 Program along with F-Prot AVS.
)) Neither was able to detect it.
))
)) Please be careful and send this to as many people as possible,
)) so maybe this new virus can be eliminated.
))
)) Please pass this on,...........to anyone you know
))
)) This information was received this morning from IBM, please
)) share it with anyone that might access the Internet mail
)) system.
))
)) If anyone receives e-mail entitled "PENPAL GREETINGS!" please
)) delete it WITHOUT READING IT!! This is a warning for all
)) Internet mail users - there is a dangerous virus propagating
)) across the Internet through an e-mail message entitled "PENPAL
)) GREETINGS!"
))
)) DO NOT DOWNLOAD ANY MESSAGE ENTITLED "PENPAL GREETINGS"!!
)) This message appears to be a friendly letter asking you if you
)) are interested in a penpal, but by the time you read the
)) letter, it is too late.
))
)) The "trojan horse" virus will have already infected the boot
)) sector of your hard drive, destroying all of the data present.
)) It is a self-replicating virus, and once the message is read,
)) it will AUTOMATICALLY forward itself to anyone whose e-mail
)) address is present in YOUR mailbox!
))
)) This virus will DESTROY your hard drive, and holds the
)) potential to DESTROY the hard drive of anyone whose mail is in
)) your IN BOX, and whose mail is in their in box and so on.
))
)) If this virus keeps getting passed, it has the potential to do
)) a great deal of damage to computer networks worldwide!!!!
Regards
Adriaan
ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
Name: Adriaan van Niekerk
Company: Institute for Agricultural Engineering (ARC)
Address: Private Bag X 519
Silverton
South Africa
0127
Telephone: International: 02712 842 4037
Local: 012 842 4037
Fax: International: 02712 804 0753
Local: 012 804 0753
E-mail: irri7@ing1.agric.za
ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
------------------------------
Date: Tue, 9 Sep 1997 06:44:24 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: Re: ALUMINUM TOXICITY 1
Regarding a recent posting on Alumimum:
) 1.. For normal irrigation, there are devices which impart a high
)electronegative charge on water and cause about a 20% drop in surface
)tension. The effect of the reduction in surface tension is the water
)will dissolve more nutrients from the soil and carry them to the
)plant.(.System cost about $3000.00
)with almost no maintainence; uses about seven cents of electricity per
)day.)
First of all, what is surface tension? I have never heard of this as a
chemical phenomena. Secondly, we've already gone through several
discussions on electro charging water..doesn't seem to be any merit in
this. Please check out:
- http://www.mif.org/ion.html on the Microirrigation Forum web site
Don't mean to sound too skeptical, but I am yet to be convinced of such a
technology. Why isn't 'Control of Colloidal Stabilty through Zeta
Potential' by Thomas Riddick in a Scientific Journal? or is it? I need more
objective facts.
Sincerely,
Richard Mead
Trickle-L owner/manager
www.mif.org
------------------------------
Date: Tue, 9 Sep 1997 06:44:33 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: Re: New emitter technology
The following is from Gerard Pothuis regarding my query on ADI technology.
Gerard has been having Trickle-L posting problems. If any of you also share
this problem, please notify me personally and not the group.
RMM
----------------------
)To : Richard Mead
)Ref : ADI
)
)Dear Richard
)
)I have been "lurking" on your trickel list for quite a while, mainly
because of some hiccup
)in the system which doesn't let me reply to the trickel list directly.
Although as you can check
)being on the receiving end. Perhaps some more subscribers are
experiencing the same
)problem ?
)Anyway, to come to the point, we have been using ADI from Metzer / Lego
here in Ecuador
)for quite a while ( aprox.. two years ). We are using it because of it's
autoregulation qualities
)which are very good. We did not use the dripper with dirty or problematic
water yet, but will
)definitively give it a try after your remarks
)
)Best Regards
)
)Gerard Pothuis
)NITZAN AGRO-SYSTEMS
)
)
)Gerard Pothuis
)
)Internet: gpothuis@pi.pro.ec
)
)
------------------------------
Date: Tue, 9 Sep 1997 11:15:06 -0400
From: GroAire@AOL.COM
Subject: Re: Porous pipe made from recycled tires
Be very careful in purchasing porous tubing made from recycled tires. The
steel belted radials that are ground up cause the pipe to rust shut after a
period of years or sometimes even months. A dealer almost ruined the drip
irrigation martket here in the Denver area by selling this inferior product
to the public. It didn't take very long for the public to obtain a general
sense that subsurface drip irrigation doesn't work and was something to stay
away from.Also watch out for calcium carbonate levels in your water as well
as other minerals. It has been an uphill battle to educate the public about
successful subsurface irrigation in crops and turf, but I'm confident we'll
win the day.
Dave Enyeart
GroAire@aol.com
------------------------------
Date: Mon, 8 Sep 1997 17:48:34 -0400
From: Frank Hartman (suemc@GATE.NET)
Subject: Re: ALUMINUM TOXICITY 1
Richard Mead wrote:
) Regarding a recent posting on Alumimum:
)
) ) 1.. For normal irrigation, there are devices which impart a high
) )electronegative charge on water and cause about a 20% drop in surface
) )tension. The effect of the reduction in surface tension is the water
) )will dissolve more nutrients from the soil and carry them to the
) )plant.(.System cost about $3000.00
) )with almost no maintainence; uses about seven cents of electricity per
) )day.)
)
) First of all, what is surface tension? I have never heard of this as a
) chemical phenomena. Secondly, we've already gone through several
) discussions on electro charging water..doesn't seem to be any merit in
) this. Please check out:
)
) - http://www.mif.org/ion.html on the Microirrigation Forum web site
)
) Don't mean to sound too skeptical, but I am yet to be convinced of such a
) technology. Why isn't 'Control of Colloidal Stabilty through Zeta
) Potential' by Thomas Riddick in a Scientific Journal? or is it? I need more
) objective facts.
)
) Sincerely,
)
) Richard Mead
) Trickle-L owner/manager
) www.mif.org
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files (graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
Lets see if I can answer your questions one at a time.
1. Surface tension is what holds a drop of water together. Normal water in the
US is about 75 dynes/cm as it comes from the tap. (using a Fisher Ring
tensionometer). Surface tension is the quality of water that allows a water
spider to walk on the surface or allows one to float a needle on the surface.
Surface tension is decreased by surfacants, or by increasing Zeta Potential
i.e. electronegative charge on colloids in suspension. The water becomes
wetter, feels like soft water but without the calcium/sodium exchange from a
water softener. Raising water to a boil decreases surface tension to about 55
dynes/cm which causes water to dissolve better. In essence, it is wettter
water.
2. As to the comments on ionized water- As with most things, until we
understand the mechanism by which things work, results are spotty. The
ionization site focuses on magnetic water treatment. The
ASHRAE works in keeping down scale in Heating and AC units as do studies by
NASA, DOD and the Air Force. The problem is that magnetic treatment will not
work consistently and, when it doesn't,
and the mechanism of action isn't understood, what do you do then.Looking at
the comments on the site, it appears that this is what happened. This has been
the case for many of the non-chemical devices for water treatment and we have
experimented with at least 20 different ones.
3.There is no magic or mystery in what was described and the science of surface
charge and Zeta
Potential has been around for 100 years. The practical implications have not
been recognized because the frame of reference for most people is ionic
chemistry not colloidal. Al toxicity is a colloidal problem that cannot be
solved with ionic chemistry.
4. Ridddicks work is a book of 370 pages and it is considered a seminal work in
ZP. It will be an eye opener. The implications of this go far beyong
agriculture.I would suggest getting the first reference
from Zeta Meter on the five minute course.
Hope this answers some of your questions.
Frank H
------------------------------
Date: Tue, 9 Sep 1997 17:00:54 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: ALUMINUM TOXICITY: The debate continues
Frank,
Excellent rebuttal. Now that I've gone through my soil physics memory
banks, I do recall studying water surface tension (Hillel: Soil and Water).
Thus, I didn't mean to lie when I said I've never heard of this chemical
phenomena when actually it's more physical.
Nevertheless, I'm puzzled how any of this has relevance to normal irrigated
agriculture. Specifically to:
)The practical implications have not
)been recognized because the frame of reference for most people is ionic
)chemistry not colloidal. Al toxicity is a colloidal problem that cannot be
)solved with ionic chemistry.
My questions here is; does the plant respond to colloidal chemistry or
ionic chemistry? I would think ionic due to the ionic exchange at the
soil-root interface. It seems when the pH of a soil is too low, Al ions are
toxic to plants, even as low as 1 ppm. Thus, are we to measure and correct
this problem using colloidal thinking via changing the zeta potential?
What's the difference if its colloidal or ionic if we just need to add lime
[CaCO3] to the acid/Al toxic soil?
This is all very interesting and I would like to continue, but let's focus
on how drip irrigation per se would implement then contribute to enhancing
the soil from such technology. I guess what I'm saying is, this is NOT
Zeta-potential-L. So, what would be needed to change the zeta potential of
irrigation water which consequently would change the zeta potential of
soil-water?
Thanks again Frank for reminding me of my physical chemistry (blush) and
enlightening us with an interesting yet curious concept.
Any other physical chemist out there yearning to respond?
Richard Mead
Trickle-L owner/manager
------------------------------
Date: Tue, 9 Sep 1997 17:45:29 +0000
From: Todd Hurlburt (toddh@MAIL.EWA.NET)
Subject: Water treatments
I have been having difficulty getting unbiased information about water
treatments for my drip system. My irrigation equipment supplier told me to
go to suppliers of acid, chlorine, etc. The suppliers are trying to sell
certain products (high profit items?), plus I'm not convinced I am getting
information about what I need to accomplish.
My water source is from an irrigation system that diverts river water. My
filtration system is disk filters.
I got some information from the Trickle-L archives, but I was wondering if
there is some more comprehensive source that would also be unbiased.
Thanks for any help.
Todd Hurlburt
------------------------------
Date: Mon, 8 Sep 1997 21:59:24 -0400
From: Frank Hartman (suemc@GATE.NET)
Subject: Re: ALUMINUM TOXICITY: The debate continues
Richard Mead wrote:
) Frank,
)
) Excellent rebuttal. Now that I've gone through my soil physics memory
) banks, I do recall studying water surface tension (Hillel: Soil and Water).
) Thus, I didn't mean to lie when I said I've never heard of this chemical
) phenomena when actually it's more physical.
)
) Nevertheless, I'm puzzled how any of this has relevance to normal irrigated
) agriculture. Specifically to:
)
) )The practical implications have not
) )been recognized because the frame of reference for most people is ionic
) )chemistry not colloidal. Al toxicity is a colloidal problem that cannot be
) )solved with ionic chemistry.
)
) My questions here is; does the plant respond to colloidal chemistry or
) ionic chemistry? I would think ionic due to the ionic exchange at the
) soil-root interface. It seems when the pH of a soil is too low, Al ions are
) toxic to plants, even as low as 1 ppm. Thus, are we to measure and correct
) this problem using colloidal thinking via changing the zeta potential?
) What's the difference if its colloidal or ionic if we just need to add lime
) [CaCO3] to the acid/Al toxic soil?
)
) This is all very interesting and I would like to continue, but let's focus
) on how drip irrigation per se would implement then contribute to enhancing
) the soil from such technology. I guess what I'm saying is, this is NOT
) Zeta-potential-L. So, what would be needed to change the zeta potential of
) irrigation water which consequently would change the zeta potential of
) soil-water?
)
) Thanks again Frank for reminding me of my physical chemistry (blush) and
) enlightening us with an interesting yet curious concept.
)
) Any other physical chemist out there yearning to respond?
)
) Richard Mead
) Trickle-L owner/manager
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files (graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
Great! lets stick to the practical. The effect of impressing a
electronegative charge on irrigation water is the following:
1. Elimination of scale and algae in the line although at first there may be an
increase as scale formed inside the pipe goes back into suspension.
2. major increase in plant vitality and disease resistance as nutrients
including trace chemicals locked up in soil are freed by the change in surface
temsion which disolves them..
3. Reduction or elimination of the need for supplemental feeding as the plant
can now take up the nutrients that have been unlocked from the soil.
By reducing the artificial feeding, salting out of soils from fertilizer
salts is eliminated.
This part I don't understand unlesss Professor Phil Callahan is right about
insects being drawn to less healthy plants.In adjacent rows of corn and lima
beans (treated vs untreated0
no bean beetle damage and very minor corn borer on the treated without
pesticides and
normal damage on the untreated using pesticide. Go figure?
A lot of what has been done in the past is treating symptoms. Addressing
Zeta potential
treats the cause.
When cause is understood, treatment becomes simple. Ocam's razor.
I hope this clears some of this up.
PS I am using a new version of netscape and clicking " return to sender" not
sender and all recipients. If this isn't going to where it should let me know
kindest regards
Frank H.
------------------------------
Date: Wed, 10 Sep 1997 14:19:25 +0930
From: meissner.tony@WPO.PI.SA.GOV.AU
Subject: Re PENPAL virus Another hoax
This is the advice I received from our IT people.
I am on a mailing list of two recognised security sources that advise on computer vulnerabilities
and these type of threats. "JOIN THE CREW" and "PENPAL GREETINGS" have been identified
as Internet e-mail hoaxes. "AOL4FREE.COM" was a program that was supposed to steal free
Internet access time from a particular Internet Service Provider. A hoax was spread to suggest
that it would destroy hard disks.
The Internet e-mail hoaxes are the equivalent of chain letters and rely on people sending them to
10 of their friends and so on. The warnings are the point of the e-mails and they prey on the need
to warn your friends/colleagues. The real damage done by these e-mails is the needless worry,
the sending and responding to the e-mails.
For your own information opening an e-mail message is not dangerous in itself. The danger is if
there are any attachments to the e-mail which are saved and run. These attachments can be
programs that detroy a the contents of a hard disk. These programs will not be detected by virus
scanners as viruses, unless they actually do contain a virus. Therefore the rule is not to run any
programs sent from unknown sources, especially any unsolicited e-mail. The problem is that
e-mails of this type will usually have a extremely convincing spiel on why you cannot live with out
the program, so be wary.
The other rule is to back up your C: drive often. This is good practice and should be done
regardless of these types of threats.
Tony Meissner
*********************************************
*Senior Research Scientist (Irrigation) *
*Irrigated Crop Management Service *
*South Australian Research & Development *
*Institute, Loxton Centre, *
* PO Box 411, Loxton SA Aust 5333 *
*Tel: +61 8 85 95 9146 *
*Fax: +61 8 85 95 9180 *
*email: meissner.tony@pi.sa.gov.au *
*********************************************
------------------------------
End of TRICKLE-L Digest - 8 Sep 1997 to 9 Sep 1997
**************************************************
Date: Thu, 11 Sep 1997 00:02:00 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 9 Sep 1997 to 10 Sep 1997
There are 8 messages totalling 450 lines in this issue.
Topics of the day:
1. (Fwd) (Fwd) VIRUS WARNING
2. Re PENPAL virus Another hoax (2)
3. Porous pipe made from recycled tires
4. porous hose
5. Water treatments (2)
6. ALUMINUM TOXICITY: The debate continues
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Wed, 10 Sep 1997 00:44:05 -0600
From: bricmont (bricmont@CRUZIO.COM)
Subject: Re: (Fwd) (Fwd) VIRUS WARNING
At 03:11 PM 9/9/97 +0000, Adriaan van Niekerk wrote:
)Bryan,
)Thank you for letting me know that the message did not came through
)completly. My apology to the group!!
)I wil try once more. I think I know what the problem was and I have
)hopefully corrected it. Here goes!
)
)
)
)
)------- Forwarded Message Follows -------
)From: "Anelda Dorfling" (ING1/DATA5)
)To: #everyone
)Date: Tue, 9 Sep 1997 08:45:18 GMT-2
)Subject: (Fwd) VIRUS WARNING
)
)------- Forwarded Message Follows -------
)
)) IMPORTANT!!!!
)))
))) A few hours ago, Someone opened an E-mail that had the subject
))) heading of ao4free.com
)))
))) Within seconds of opening it, a window appeared and began to
))) display all files that were being deleted. The user immediately
))) shut down the computer, but it was too late.
)))
))) This virus wiped all out. It ate the Anti-Virus Software that
))) comes with the Windows '95 Program along with F-Prot AVS.
))) Neither was able to detect it.
)))
))) Please be careful and send this to as many people as possible,
))) so maybe this new virus can be eliminated.
)))
))) Please pass this on,...........to anyone you know
)))
))) This information was received this morning from IBM, please
))) share it with anyone that might access the Internet mail
))) system.
)))
))) If anyone receives e-mail entitled "PENPAL GREETINGS!" please
))) delete it WITHOUT READING IT!! This is a warning for all
))) Internet mail users - there is a dangerous virus propagating
))) across the Internet through an e-mail message entitled "PENPAL
))) GREETINGS!"
)))
))) DO NOT DOWNLOAD ANY MESSAGE ENTITLED "PENPAL GREETINGS"!!
))) This message appears to be a friendly letter asking you if you
))) are interested in a penpal, but by the time you read the
))) letter, it is too late.
)))
))) The "trojan horse" virus will have already infected the boot
))) sector of your hard drive, destroying all of the data present.
))) It is a self-replicating virus, and once the message is read,
))) it will AUTOMATICALLY forward itself to anyone whose e-mail
))) address is present in YOUR mailbox!
)))
))) This virus will DESTROY your hard drive, and holds the
))) potential to DESTROY the hard drive of anyone whose mail is in
))) your IN BOX, and whose mail is in their in box and so on.
)))
))) If this virus keeps getting passed, it has the potential to do
))) a great deal of damage to computer networks worldwide!!!!
)
)
)
)Regards
)Adriaan
)
)
)
)ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
)Name: Adriaan van Niekerk
)Company: Institute for Agricultural Engineering (ARC)
)Address: Private Bag X 519
) Silverton
) South Africa
) 0127
)Telephone: International: 02712 842 4037
) Local: 012 842 4037
)Fax: International: 02712 804 0753
) Local: 012 804 0753
)E-mail: irri7@ing1.agric.za
)
)ooooooooooooooooooooooooooooooooooooooooooooooooooooooooooo
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
).-
)
)
Bernard "Barney" Bricmont 1920 Maciel Ave. Santa Cruz, CA 95062-1902
voice 408-476-0504 fax 408-475-2638
------------------------------
Date: Wed, 10 Sep 1997 00:52:15 -0700
From: Robert Carian (grapegrower@EARTHLINK.NET)
Subject: Re: Re PENPAL virus Another hoax
)The other rule is to back up your C: drive often. This is good practice
)and should be done
)regardless of these types of threats.
Or just get a mac and be done with all things virus and 2000ad.
------------------------------
Date: Wed, 10 Sep 1997 22:57:45 +1000
From: Wally Menke (wallym@OZEMAIL.COM.AU)
Subject: Re: Porous pipe made from recycled tires
At 10:25 AM 4/09/97 -0400, you wrote:
)Trickle Members,
)
)Can anyone fill me in on the use of recycled and ground tires being used to
)make porous pipe for subirrigation. It's my understanding that this type
)of pipe is being buried 1 meter deep and being used in subirrigation.
)
)Who makes this? Where is it sold? How much does it cost? What is the
)performance experience with it?
)
)Any info would be greatly appreciated.
)
)Larry
)++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
)++++++
)Larry D. Geohring, Sr. Extension Associate
)Department of Agricultural and Biological Engineering
)212 Riley Robb
)Cornell University
)Ithaca, NY 14853
Dear Larry
Save your valuable time and effort on this tangent as pourous pipe is
regarded in the serious irrigation world as another means of turning old
tyres into landfill in other peoples gardens or farms. And getting them to
part with $$ on the way. There has been much written on these products,
including a 75 page thesis I have from Sydney University to show that the
uniformity and consistency of output is nothing short of astonishingly bad.
Basically the pours are very fine say 50 micron and a torturous path. In
theory to protect the pours you would need to filter down to say 10 micron,
which in the real world of irrigation is not practical. I have seen and
heard of numerous disasters with these types of products, if you get 2 years
use you may be luck.
Save yourself the headaches, use a turbulent flow dripline with built in
root protect like Geoflow Rootguard, it has a 10 year warranty.
Regards
Wally Menke - Triangle Filtration
------------------------------
Date: Tue, 9 Sep 1997 15:51:37 -0700
From: Jochen Eberhard (Jochen.Eberhard@T-ONLINE.DE)
Subject: Re: porous hose
Craig A. Storlie wrote:
)
) Porous Pipe - Tire Mire?
)
) I didn't know porous pipe could be purchased so cheaply $9/80
ft =
) $0.11/ft). That is substantially cheaper than some of the industry's
) top-shelf products but 2-3 times the cost of products that are being
) used in ag for subsurface drip irrigation.
)
) The others are right about the uniformity issues. For a GAIA
3/8" ID
) porous hose, CIT reported a CV of 0.481, a discharge exponent of
1.14,
) and Design Emission Uniformities ranging from 36-39% (all for
ressures
) ranging from 1-7 psi). In comparison to other drip products, these
) values are poor.
)
) However, porous hose certainly gets a lot of attention! BUT
WHY? Is
) it ease of use (P regulation, filtering, fittings), cost, longevity,
or
) just good marketing? I would appreciate hearing reasons from the
ist.
)
) Craig Storlie
) Extension Specialist in Agricultural Engineering
) Rutgers University
I do not know either why there is so much attention on the porous pipe
even here in Germany. Maybe it is the word *recycled* that makes it
popular. An used tires are a cheap material, one usually gets paid for
if he takes them. So this kind of deal is the best one can make: to get
paid for the tires and get paid again for the porpus pipe.
We had it in an asparagus field for testing on our vegetable research
farm for one or two years. Then we took some 100 meter out, kept it wet
(like the manufacturer told us) and tested it on discharge variation.
The results were so disappointing that we do not recommend it for
agricultural purposes. The discharge rate changed dramaticaly every
running meter and after the first 20 to 30 meters it generally declined
to about 10 to 20% at the end of the line. There was hardly any water
coming out of the pipe at the end no matter if we injected the water
the one end or the other. A test in the field with water meters showed
similar results. As far as I am informed the product disappeared from
the agricultural scene but is propagated for home gardens with a lengt
of 10 to 15 meters what might work very well for a good numbers of
years.
My personal opinion: I would use it for my lawn - it is better than
doing the spinkling by hand - but I would not use it for agricultural
production even if I would get paid for.
Best regards
_____________________________________________________________
| Jochen Eberhard * * |
| SLFA Versuchsbetriebe ( \ / ) |
| Queckbrunnerhof \ / |
| Dannstadter Str. 91 --- |
| 67105 Schifferstadt (o|o) |
| Germany ( ~~~ ) |
| ( ) |
| Tel: 0049 - 6235 - 2672 ( ) |
| Fax: - - 82741 ( ooO Ooo ) |
| email: Jochen.Eberhard@t-online.de |
|_____________________________________________________________|
------------------------------
Date: Wed, 10 Sep 1997 10:20:50 -0400
From: "Dr. Don Pitts" (djp@ICON.IMOK.UFL.EDU)
Subject: Re: Water treatments
Todd,
Please provide a mailing address.
Don Pitts
University of Florida
At 05:45 PM 9/9/97 +0000, you wrote:
)I have been having difficulty getting unbiased information about water
)treatments for my drip system. My irrigation equipment supplier told me to
)go to suppliers of acid, chlorine, etc. The suppliers are trying to sell
)certain products (high profit items?), plus I'm not convinced I am getting
)information about what I need to accomplish.
)
)My water source is from an irrigation system that diverts river water. My
)filtration system is disk filters.
)
)I got some information from the Trickle-L archives, but I was wondering if
)there is some more comprehensive source that would also be unbiased.
)
)Thanks for any help.
)
)Todd Hurlburt
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
------------------------------
Date: Wed, 10 Sep 1997 10:04:46 -0700
From: "J.D. Oster" (oster@MAIL.UCR.EDU)
Subject: Re: Water treatments
Todd: If you send me an analysis of the water (Na, Ca, Mg, K, HCO3, Cl,
SO4, and B, I may be able to help. At 05:45 PM 9/9/97 +0000, you wrote:
)I have been having difficulty getting unbiased information about water
)treatments for my drip system. My irrigation equipment supplier told me to
)go to suppliers of acid, chlorine, etc. The suppliers are trying to sell
)certain products (high profit items?), plus I'm not convinced I am getting
)information about what I need to accomplish.
)
)My water source is from an irrigation system that diverts river water. My
)filtration system is disk filters.
)
)I got some information from the Trickle-L archives, but I was wondering if
)there is some more comprehensive source that would also be unbiased.
)
)Thanks for any help.
)
)Todd Hurlburt
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
J.D.(Jim) Oster
Soil and Water Specialist and Adjunct Professor
Soil and Environmental Sciences
University of California
Riverside, CA.
FAX: 909 787-5522
P.O Box 1344
Graeagle CA 96103
Telehones
VOICE:
Riverside Office 909 787-5100 Nov 1997
Graeagle Office 916 8360938 May through October 1997
e-mail: Oster@mail.ucr.edu
http://esce.ucr.edu
------------------------------
Date: Wed, 10 Sep 1997 10:04:47 -0700
From: "J.D. Oster" (oster@MAIL.UCR.EDU)
Subject: Re: ALUMINUM TOXICITY: The debate continues
Zeta Potential of a particle suspended in water can be measured; it is the
chemical potential at the boundary between the water which moves with the
particle (hydration shell) and the rest of the water. The water itself does
not have a zeta potential.
Aluminum (Al) toxicity: This is very dependent on the pH of the soil. Al
forms complexes with hydroxyls (OH ions) and the degree of complex
formation depends on pH. At a pH of 3, Al is not associated with hydroxyls,
consequently it is a simple, hydrated ion in water, with a charge of plus
3. This form is toxic to plants. At higher pH's, the aluminum hydroxide
complexes begin to form, and the charge of the complexes varies. It
decreases from plus 2.9 to near zero as the pH increases from 3 to about 8.
What all this means in terms of flocculation (adding alum (aluminum
sulfate)) to enhance flocculation and remove suspended colloids in water
and Al toxicity to plants is an interesting subject. I will pose a
generalization: The addition of alum to flocculate suspended solids will
not cause a problem with Al toxicity unless the pH of the soil solution, to
which the treated water is applied, is less than 5. in At 05:00 PM 9/9/97
-0700, you wrote:
)Frank,
)
)Excellent rebuttal. Now that I've gone through my soil physics memory
)banks, I do recall studying water surface tension (Hillel: Soil and Water).
)Thus, I didn't mean to lie when I said I've never heard of this chemical
)phenomena when actually it's more physical.
)
)Nevertheless, I'm puzzled how any of this has relevance to normal irrigated
)agriculture. Specifically to:
)
))The practical implications have not
))been recognized because the frame of reference for most people is ionic
))chemistry not colloidal. Al toxicity is a colloidal problem that cannot be
))solved with ionic chemistry.
)
)My questions here is; does the plant respond to colloidal chemistry or
)ionic chemistry? I would think ionic due to the ionic exchange at the
)soil-root interface. It seems when the pH of a soil is too low, Al ions are
)toxic to plants, even as low as 1 ppm. Thus, are we to measure and correct
)this problem using colloidal thinking via changing the zeta potential?
)What's the difference if its colloidal or ionic if we just need to add lime
)[CaCO3] to the acid/Al toxic soil?
)
)This is all very interesting and I would like to continue, but let's focus
)on how drip irrigation per se would implement then contribute to enhancing
)the soil from such technology. I guess what I'm saying is, this is NOT
)Zeta-potential-L. So, what would be needed to change the zeta potential of
)irrigation water which consequently would change the zeta potential of
)soil-water?
)
)Thanks again Frank for reminding me of my physical chemistry (blush) and
)enlightening us with an interesting yet curious concept.
)
)Any other physical chemist out there yearning to respond?
)
)Richard Mead
)Trickle-L owner/manager
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
J.D.(Jim) Oster
Soil and Water Specialist and Adjunct Professor
Soil and Environmental Sciences
University of California
Riverside, CA.
FAX: 909 787-5522
P.O Box 1344
Graeagle CA 96103
Telehones
VOICE:
Riverside Office 909 787-5100 Nov 1997
Graeagle Office 916 8360938 May through October 1997
e-mail: Oster@mail.ucr.edu
http://esce.ucr.edu
------------------------------
Date: Wed, 10 Sep 1997 14:33:56 -0700
From: "Alan S. Wicks" (awicks@TELEVAR.COM)
Subject: Re: Re PENPAL virus Another hoax
Greetings,
I strongly suggest that each of us bookmark the following page.
http://www.kumite.com/myths/
The title is "Computer Virus Myths home page". It discusses the history
of viruses - real and imagined.
Sincerely,
Alan Wicks
------------------------------
End of TRICKLE-L Digest - 9 Sep 1997 to 10 Sep 1997
***************************************************
Date: Fri, 12 Sep 1997 00:02:54 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 10 Sep 1997 to 11 Sep 1997
There are 2 messages totalling 157 lines in this issue.
Topics of the day:
1. ALUMINUM TOXICITY: The debate continues (2)
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Wed, 10 Sep 1997 12:03:29 -0400
From: Frank Hartman (suemc@GATE.NET)
Subject: Re: ALUMINUM TOXICITY: The debate continues
J.D. Oster wrote:
) Zeta Potential of a particle suspended in water can be measured; it is the
) chemical potential at the boundary between the water which moves with the
) particle (hydration shell) and the rest of the water. The water itself does
) not have a zeta potential.
)
) Aluminum (Al) toxicity: This is very dependent on the pH of the soil. Al
) forms complexes with hydroxyls (OH ions) and the degree of complex
) formation depends on pH. At a pH of 3, Al is not associated with hydroxyls,
) consequently it is a simple, hydrated ion in water, with a charge of plus
) 3. This form is toxic to plants. At higher pH's, the aluminum hydroxide
) complexes begin to form, and the charge of the complexes varies. It
) decreases from plus 2.9 to near zero as the pH increases from 3 to about 8.
)
) What all this means in terms of flocculation (adding alum (aluminum
) sulfate)) to enhance flocculation and remove suspended colloids in water
) and Al toxicity to plants is an interesting subject. I will pose a
) generalization: The addition of alum to flocculate suspended solids will
) not cause a problem with Al toxicity unless the pH of the soil solution, to
) which the treated water is applied, is less than 5. in At 05:00 PM 9/9/97
) -0700, you wrote:
) )Frank,
) )
) )Excellent rebuttal. Now that I've gone through my soil physics memory
) )banks, I do recall studying water surface tension (Hillel: Soil and Water).
) )Thus, I didn't mean to lie when I said I've never heard of this chemical
) )phenomena when actually it's more physical.
) )
) )Nevertheless, I'm puzzled how any of this has relevance to normal irrigated
) )agriculture. Specifically to:
) )
) ))The practical implications have not
) ))been recognized because the frame of reference for most people is ionic
) ))chemistry not colloidal. Al toxicity is a colloidal problem that cannot be
) ))solved with ionic chemistry.
) )
) )My questions here is; does the plant respond to colloidal chemistry or
) )ionic chemistry? I would think ionic due to the ionic exchange at the
) )soil-root interface. It seems when the pH of a soil is too low, Al ions are
) )toxic to plants, even as low as 1 ppm. Thus, are we to measure and correct
) )this problem using colloidal thinking via changing the zeta potential?
) )What's the difference if its colloidal or ionic if we just need to add lime
) )[CaCO3] to the acid/Al toxic soil?
) )
) )This is all very interesting and I would like to continue, but let's focus
) )on how drip irrigation per se would implement then contribute to enhancing
) )the soil from such technology. I guess what I'm saying is, this is NOT
) )Zeta-potential-L. So, what would be needed to change the zeta potential of
) )irrigation water which consequently would change the zeta potential of
) )soil-water?
) )
) )Thanks again Frank for reminding me of my physical chemistry (blush) and
) )enlightening us with an interesting yet curious concept.
) )
) )Any other physical chemist out there yearning to respond?
) )
) )Richard Mead
) )Trickle-L owner/manager
) )
) ) ##############################################################
) )Attention list subscribers! Please DO NOT send any attached files (graphics
) )or text documents) to the Trickle-L list. If experiencing any problems
) )obtaining Trickle-L information, please contact the list owner, Richard
) )Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ) ##############################################################
) )
) J.D.(Jim) Oster
) Soil and Water Specialist and Adjunct Professor
) Soil and Environmental Sciences
) University of California
) Riverside, CA.
) FAX: 909 787-5522
)
) P.O Box 1344
) Graeagle CA 96103
)
) Telehones
) VOICE:
) Riverside Office 909 787-5100 Nov 1997
) Graeagle Office 916 8360938 May through October 1997
)
) e-mail: Oster@mail.ucr.edu
) http://esce.ucr.edu
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files (graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
Jim
Thanks for the reply. I agree with your generalization on pH and aluminum
toxicity but if we look at
that as a symptom and look to the change in zP as the cause the picture
changes.. All the studies have focused on ionic changes in solution when
unsuccessfully trying to understand the method of aluminum toxicity.
Given that reduction of ph reduces the Zeta potential and the solution is in
the -15 to -25mv range, the reduction in zP drops the solution past the
threshold of agglomeration; so nutrients are no longer
carried as colloids in solution.
This is something for the research guys to determine.
From a practical standpoint, when an electronegative charge is induced
artificially on the solution say by electrostatics, aluminum toxicity
disappears. No change in pH,; no change in chemistry. Plants suddenly thrive and
material like calcium and algae which caused a prolem with clogging of nozzles
disappear. There may be an initial period of higher clogging unless the system
is flushed. This is due to the material like scale which has adhered to pipe in
the past breaking free from the pipe wall. After the initial period, the water
will remain clear with no scale or algae.
So If we look at aluminum toxicity as a pure zP problem, a different
picture emerges. Even where aluminum toxity is not a problem, the same results
occur. In part, the increase in growth and reduction in feeding requirements may
be from two factors:
1. By keeping small particles in suspension, they are more bioavailable to the
plant. As a corollary,
toxic materials such as metals seem to lose their toxicity as colloids. Another
one for the research guys.
2. Why surface tension decreases as ZP rises isn't clear but, it clearly does.
If you have an explanation for that, it would be appreciated. The reduced
surface tension of the water produces wetter water which dissolves material from
the soil and makes it bio avaiialble.
All this started 7 years ago when changing the zP of aqueos solutions with
no chemisrty change
caused impressive effects which didn't fit the ionic model.The zP model accounts
for a whole series of analmous effects that have been observed by various
experimenters.
------------------------------
Date: Thu, 11 Sep 1997 11:35:13 -0700
From: charles e kome (cek9749@USL.EDU)
Subject: Re: ALUMINUM TOXICITY: The debate continues
I need information on practical and economic methods to reduce the pH of
water used to clean sugarcane at a sugar refinery. About 3000 galons
per minute of water are needed to clean sugarcane at a refinery that
runs 24 hours a day for about 90 to 100 days each year. The resulting
water drops to a pH level between 3 and 4. Disposal of this water is
into wetlands has resulted in fish kills and dead birds. Quick lime is
being used every other day to treat the water but this is very
expensive. Are there ways to reduce the acidification procces or
accelerate complete oxidation of these sugar substrates?
------------------------------
End of TRICKLE-L Digest - 10 Sep 1997 to 11 Sep 1997
****************************************************
Date: Sat, 13 Sep 1997 00:02:11 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 11 Sep 1997 to 12 Sep 1997
There are 2 messages totalling 92 lines in this issue.
Topics of the day:
1. unsubscribe
2. Fwd: Schedule
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Fri, 12 Sep 1997 09:08:58 -0400
From: "Dr. Don Pitts" (djp@ICON.IMOK.UFL.EDU)
Subject: unsubscribe
Richard,
I have decided to leave the University of Florida, so please unsubscribe
me from Trickle-L.
My new address will be NRCS, USDA, 1902 Fox Drive, Champaign, IL 61820
(Ph. 217-398-5272). I'll be in the process of moving for the next two or
three weeks.
Don Pitts
------------------------------
Date: Fri, 12 Sep 1997 11:52:57 -0400
From: Tim1Utah@AOL.COM
Subject: Fwd: Schedule
FYI
---------------------
Forwarded message:
From: lori@irrigation.org (Lori Brown)
To: Tim1Utah@aol.com (Tim)
Date: 97-09-10 02:06:26 EDT
THE IRRIGATION ASSOCIATION EDUCATION SCHEDULE
ALABAMA
AUBURN
ELECTRICAL TROUBLESHOOTING - SEPTEMBER 14, 1997
SPONSORED BY: ALABAMA IRRIGATION ASSOCIATION
NEW MEXICO
RUIDOSO
LANDSCAPE IRRIGATION AUDITOR - SEPTEMBER 15-16, 1997
SPONSORED BY THE NEW MEXICO IRRIGATION ASSOCIATION
HOSTED BY RMSAWWWA/RMWEA
CALIFORNIA
CORONA
INSTALLATION SUMMER CAMP - OCTOBER 6-10, 1997
SPONSORED BY CALIFORNIA LANDSCAPE CONTRACTORS ASSOCIATION
RIVERSIDE CORONA CONSERVATION DISTRICT
HOSTED BY CITY OF CORONA
NEW YORK
PLAINVIEW
LANDSCAPE IRRIGATION AUDITOR - OCTOBER 15-16, 1997
SPONSORED BY LONG ISLAND IRRIGATION ASSOCIATION
HOSTED BY CORNELL COOPERATIVE EXTENSION
TEXAS
MIDLAND/ODESSA
UNDERSTANDING PUMPS - NOVEMBER 11, 1997
GRAPEVINE
ELECTRICAL TROUBLESHOOTING - NOVEMBER 12, 997
SPRINKLER SYSTEM SCHEDULING
SAN MARCOS
ELECTRICAL TROUBLESHOOTING - NOVEMBER 13, 1997
SPRINKLER SYSTEM SCHEDULING
TYLER
ELECTRICAL TROUBLESHOOTING - NOVEMBER 14, 1997
DESIGN HYDRAULICS
SPONSORED BY TEXAS TURF IRRIGATION ASSOCIATION
KANSAS
KANSAS CITY
FIELD HYDRAULICS
ELECTRICAL TROUBLESHOOTING - NOVEMBER 13, 1997
SPONSORED BY WATER DISTRICT #1 OF JOHNSON COUNTY
THE IRRIGATION ASSOCIATION RESERVES THE RIGHT TO CANCEL ANY OR ALL
CLASSES AS NECESSARY.
*FOR GENERAL INFORMATION CONCERNING REGISTRATION FORMS AND INFORMATION
CONTACT:
LORI M. BROWN
EDUCATION MANAGER
PHONE: (703) 573-3551 FAX: (703) 573-1913
ADDITIONAL SITES AND DATES WILL BE FORTHCOMING
------------------------------
End of TRICKLE-L Digest - 11 Sep 1997 to 12 Sep 1997
****************************************************
Date: Tue, 16 Sep 1997 00:03:32 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 12 Sep 1997 to 15 Sep 1997
There are 3 messages totalling 152 lines in this issue.
Topics of the day:
1. (No subject given)
2. irrigation (2)
##############################################################
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or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Mon, 15 Sep 1997 17:21:19 -0400
From: Norris Powell (nlpow@VT.EDU)
Subject: (No subject given)
Subsurface microirrigated alfalfa, according to tissue analysis before the
third cutting (9 1 97) of this spring planted alfalfa (cv Cimmeron) is low
in Mg, Mn, and Zn.
What are the recommendations for nutrient application to correct the
deficiency - foliar application or water application through the irrigation
system?
The irrigation system is buried 15" beiow the soil surface with the
laterals spaced 36" apart.
Which materials and recommended rates?
Sandy soil in southeast Virginia with a soil pH = 6.2.
Any ideas will be helpful.
Norris L. Powell
Crop and Soil Environmental Sciences
Virginia Polytechnic Institute and State University
Tidewater Agricultural Research and Extension Center
6321 Holland Road
Suffolk, VA 23437
757-657-6450 ext 112
FAX: 757-657-9333
------------------------------
Date: Sun, 14 Sep 1997 19:15:09 -0400
From: Frank Hartman (suemc@GATE.NET)
Subject: Re: irrigation
Is the soil particularly low in these elements or only the plant ? You are in myold
area of the world. Born and raised in Hampton.
Kindest regards
Frank
Norris Powell wrote:
) Subsurface microirrigated alfalfa, according to tissue analysis before the
) third cutting (9 1 97) of this spring planted alfalfa (cv Cimmeron) is low
) in Mg, Mn, and Zn.
)
) What are the recommendations for nutrient application to correct the
) deficiency - foliar application or water application through the irrigation
) system?
)
) The irrigation system is buried 15" beiow the soil surface with the
) laterals spaced 36" apart.
)
) Which materials and recommended rates?
)
) Sandy soil in southeast Virginia with a soil pH = 6.2.
)
) Any ideas will be helpful.
) Norris L. Powell
) Crop and Soil Environmental Sciences
) Virginia Polytechnic Institute and State University
) Tidewater Agricultural Research and Extension Center
) 6321 Holland Road
) Suffolk, VA 23437
) 757-657-6450 ext 112
) FAX: 757-657-9333
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files (graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
------------------------------
Date: Mon, 15 Sep 1997 19:37:29 -0400
From: Norris Powell (nlpow@VT.EDU)
Subject: Re: irrigation
All three elements (Mg, Mn, and Zn) are low in these soils. We normally
use dolomitic lime, apply Zn to the soil (broadcast) for corn and use
foliar applied Mn on peanut.At 07:15 PM 9/14/97 -0400, you wrote:
)Is the soil particularly low in these elements or only the plant ? You are
in myold
)area of the world. Born and raised in Hampton.
)
)Kindest regards
)Frank
)
)Norris Powell wrote:
)
)) Subsurface microirrigated alfalfa, according to tissue analysis
before the
)) third cutting (9 1 97) of this spring planted alfalfa (cv Cimmeron) is low
)) in Mg, Mn, and Zn.
))
)) What are the recommendations for nutrient application to correct
the
)) deficiency - foliar application or water application through the irrigation
)) system?
))
)) The irrigation system is buried 15" beiow the soil surface with the
)) laterals spaced 36" apart.
))
)) Which materials and recommended rates?
))
)) Sandy soil in southeast Virginia with a soil pH = 6.2.
))
)) Any ideas will be helpful.
)) Norris L. Powell
)) Crop and Soil Environmental Sciences
)) Virginia Polytechnic Institute and State University
)) Tidewater Agricultural Research and Extension Center
)) 6321 Holland Road
)) Suffolk, VA 23437
)) 757-657-6450 ext 112
)) FAX: 757-657-9333
))
)) ##############################################################
)) Attention list subscribers! Please DO NOT send any attached files (graphics
)) or text documents) to the Trickle-L list. If experiencing any problems
)) obtaining Trickle-L information, please contact the list owner, Richard
)) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
)) ##############################################################
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
Norris L. Powell
Crop and Soil Environmental Sciences
Virginia Polytechnic Institute and State University
Tidewater Agricultural Research and Extension Center
6321 Holland Road
Suffolk, VA 23437
757-657-6450 ext 112
FAX: 757-657-9333
------------------------------
End of TRICKLE-L Digest - 12 Sep 1997 to 15 Sep 1997
****************************************************
Date: Wed, 17 Sep 1997 00:01:59 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 15 Sep 1997 to 16 Sep 1997
There are 4 messages totalling 220 lines in this issue.
Topics of the day:
1. Irrigation Coorespondence Training
2. Porous pipe made from recycled tires
3. irrigation
4. Pourous Pipe/Moisture Measurement/Wind Powered Pumping for Irrigation
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Tue, 16 Sep 1997 06:32:16 -0700
From: "Thomas L. Spofford" (tspofford@WCC.NRCS.USDA.GOV)
Subject: Irrigation Coorespondence Training
Discussion Group Members,
I have received an inquiry as to various correspondence courses
in irrigation available to individuals in developing countries. Does
anyone have a list developed on the subject that they can share
with me. I would appreciate a short description of the course and
associated costs.
Thank you for the iinformation.
Thomas L. Spofford, Irrigation Engineer
USDA - Natural Resources Conservation Service
National Water & Climate Center, Water Science & Technology
Staff
101 SW Main St., Suite 1600
Portland, OR 97204
PH (503) 414-3075 / FAX (503) 414-3101
e-mail: (tspofford@wcc.nrcs.usda.gov)
*********************************************************
"Farming looks mighty easy when your plow is a pencil and you're
a thousand miles from the corn field." Dwight D. Eisenhower (34
th. President of the United States).
*********************************************************
------------------------------
Date: Tue, 16 Sep 1997 11:26:21 -0400
From: Loren Welch (LWelch5168@AOL.COM)
Subject: Re: Porous pipe made from recycled tires
Glad to see you are also weighing in on the porous pipe question. Gary
Clarke also had a few words to say about porous pipe.
I am enjoying my semi-retirement, but do miss meeting new people and the
travel to new locations.
Later
------------------------------
Date: Tue, 16 Sep 1997 17:31:23 -0700
From: "Aron A. Quist" (stanworth@MAIL.TELIS.ORG)
Subject: Re: irrigation
Dear Norris:
I have never seen a response to zinc application to alfalfa. Our soils are
alkaline and sometimes very sandy. Out dtpa levels for zinc can be as low
as 0.3 ppm. Yet these fields have tissue levels that are adequate and
produce excellent yields of alflafla, that is 9-10 tons of hay per year (8
cuttings).
Aron
"abide in His stride"
Aron A. Quist, CPAg/SS
stanworth@mail.telis.org
Stanworth Crop Consultants, Inc.
Blythe California
v 619.922.3106, f 619.922.2770
----------
) From: Norris Powell (nlpow@VT.EDU)
) To: TRICKLE-L@crcvms.unl.edu
) Subject: Re: irrigation
) Date: Monday, September 15, 1997 4:37 PM
)
) All three elements (Mg, Mn, and Zn) are low in these soils. We
normally
) use dolomitic lime, apply Zn to the soil (broadcast) for corn and use
) foliar applied Mn on peanut.At 07:15 PM 9/14/97 -0400, you wrote:
) )Is the soil particularly low in these elements or only the plant ? You
are
) in myold
) )area of the world. Born and raised in Hampton.
) )
) )Kindest regards
) )Frank
) )
) )Norris Powell wrote:
) )
) )) Subsurface microirrigated alfalfa, according to tissue
analysis
) before the
) )) third cutting (9 1 97) of this spring planted alfalfa (cv Cimmeron) is
low
) )) in Mg, Mn, and Zn.
) ))
) )) What are the recommendations for nutrient application to
correct
) the
) )) deficiency - foliar application or water application through the
irrigation
) )) system?
) ))
) )) The irrigation system is buried 15" beiow the soil surface
with the
) )) laterals spaced 36" apart.
) ))
) )) Which materials and recommended rates?
) ))
) )) Sandy soil in southeast Virginia with a soil pH = 6.2.
) ))
) )) Any ideas will be helpful.
) )) Norris L. Powell
) )) Crop and Soil Environmental Sciences
) )) Virginia Polytechnic Institute and State University
) )) Tidewater Agricultural Research and Extension Center
) )) 6321 Holland Road
) )) Suffolk, VA 23437
) )) 757-657-6450 ext 112
) )) FAX: 757-657-9333
) ))
) )) ##############################################################
) )) Attention list subscribers! Please DO NOT send any attached files
(graphics
) )) or text documents) to the Trickle-L list. If experiencing any problems
) )) obtaining Trickle-L information, please contact the list owner,
Richard
) )) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) )) ##############################################################
) )
) ) ##############################################################
) )Attention list subscribers! Please DO NOT send any attached files
(graphics
) )or text documents) to the Trickle-L list. If experiencing any problems
) )obtaining Trickle-L information, please contact the list owner, Richard
) )Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ) ##############################################################
) )
) Norris L. Powell
) Crop and Soil Environmental Sciences
) Virginia Polytechnic Institute and State University
) Tidewater Agricultural Research and Extension Center
) 6321 Holland Road
) Suffolk, VA 23437
) 757-657-6450 ext 112
) FAX: 757-657-9333
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files
(graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
------------------------------
Date: Tue, 16 Sep 1997 20:00:57 -0700
From: ClemWehner (cww@PACIFICCOAST.NET)
Subject: Pourous Pipe/Moisture Measurement/Wind Powered Pumping for Irrigation
I have been following discussions started by
Larry Geohring's enquiry from Cornell U. Ag & Bio,
Engineering Dept. concerning recycled, ground-up
tires turned into porous pipe for sub-irrigation.
Five years ago I visited a Consulting Engineer in
West Vancourver, BC, Canada who was then trying to make
pourous pipe from tires using a process he sought,
maybe bought, from someone in Texas. The Engineer's
experimental porous-pipe production was done in association
with a nearby rubber-products manufacturer in Richmond, BC.
Sample lengths of their batches of pipe were submitted
to CIT, Fresno for evaluation.
Around that time I was doing market studies for two new
products relevant to sub-irrigation. These two new concepts were
being developed in Victoria, BC, Canada:
1) A moisture-measuring system based on Time Domain Reflectometry
(TDR). Uniquely, one design of this system's probes can measure a
profile of moisture, delivered-to-root-zone, downward, in segments
of 30cm, to depth of a meter or more. Accurate, fast and non-invasive.
2) A water-pumping system based on the phenomenon of flutter,
the bane of aircraft design and performance; but cleverly put
to work in a new wind-powered pump. This wind-powered machine
can be positioned to lift water from a well or floated -- on a
reservoir, pond, lake or river -- to move water to storage thence
distributed.
Works well in low-wind regions yet can safely withstand gale-force
blasts. Costs half that of conventional wind mills and can be
set up at ground level by one person. Uses steel cable rather
than pull-rods when mounted over a well.
Results from the above-mentioned studies are that the West Vancouver
porous-pipe-from-tires project was abandoned owing to problems
like those mentioned in Trickle-L discussions about this topic.
More positively, the TDR moisture-measuring system and the "flutter"
wind-powered water pumping system are both doing well.
Should anyone want details about these successful
irrigation-related systems: soil-moisture-measuring
or wind-powered water-pumping, I would be glad to inform
or pass your interest along for direct link with the manufacturers.
Regards,
Clem Wehner C. Wehner & Associates
Marketing Consultants International
905 Gordon Street
Victoria, BC, Canada V8W 3P9
PH/FX: 250-383-1959
E-mail: cww@pacificcoast.net
------------------------------
End of TRICKLE-L Digest - 15 Sep 1997 to 16 Sep 1997
****************************************************
Date: Thu, 18 Sep 1997 00:03:07 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 16 Sep 1997 to 17 Sep 1997
There are 5 messages totalling 137 lines in this issue.
Topics of the day:
1. Irrigation Coorespondence Training
2. lawns (3)
3. Porous pipe made from recycled tires
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Wed, 17 Sep 1997 07:49:54 -0600
From: Clare Prestwich (clarep@MAGICLINK.COM)
Subject: Re: Irrigation Coorespondence Training
At 06:32 AM 9/16/97 -0700, you wrote:
)Discussion Group Members,
)
)I have received an inquiry as to various correspondence courses
)in irrigation available to individuals in developing countries. Does
)anyone have a list developed on the subject that they can share
)with me. I would appreciate a short description of the course and
)associated costs.
)
)Thank you for the iinformation.
)
)Thomas L. Spofford, Irrigation Engineer
)USDA - Natural Resources Conservation Service
)National Water & Climate Center, Water Science & Technology
)Staff
)101 SW Main St., Suite 1600
)Portland, OR 97204
)PH (503) 414-3075 / FAX (503) 414-3101
)e-mail: (tspofford@wcc.nrcs.usda.gov)
)
)*********************************************************
)"Farming looks mighty easy when your plow is a pencil and you're
)a thousand miles from the corn field." Dwight D. Eisenhower (34
)th. President of the United States).
)*********************************************************
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
)
Tom,
Utah State University has put together a whole series of short courses I
don't know all the details but you might want to contact them. I am sure
alot of the other universities have something similar.
Clare
------------------------------
Date: Wed, 17 Sep 1997 07:14:03 -0800
From: Jerry Neufeld (jneufeld@FS.SCS.UNR.EDU)
Subject: lawns
I have a question about SDI in turf applications. Is root intrustion
a problem in turf applictions? Is there a need to inject something
through the system to inhibit root intrusion? If so what materials
should be used? What types of injection equipment should be used?
Thanks,
Jerry Neufeld
------------------------------
Date: Wed, 17 Sep 1997 07:37:44 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: Re: lawns
Jerry,
Check out:
http://www.atinet.org/cati/cit/rese/95/950104/index.html
It is a CIT article entitled Subsurface Drip Irrigation (SDI on Turfgrass:
A University Experience, By D. F. Zoldoske, S. Genito, G. S. Jorgensen
RMM
Trickle-L owner/manager
------------------------------
Date: Wed, 17 Sep 1997 20:34:10 -0700
From: Rodney Ruskin (geoflow1@SLIP.NET)
Subject: Re: lawns
At 07:14 AM 9/17/97 -0800, Jerry Neufeld wrote:
) I have a question about SDI in turf applications. Is root intrustion
) a problem in turf applictions? Is there a need to inject something
) through the system to inhibit root intrusion? If so what materials
) should be used? What types of injection equipment should be used?
)
) Thanks,
)
) Jerry Neufeld
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
Unless you use porous pipe or the odl Hardie Bi-Wall root intrusion is a
problem with SDI in any crop except concrete paving. See CIT study as
suggested by our leader Richard Mead.
No chemicals which work are registered for use in lawns.
There are only two alternatives - either ROOTGUARD by Geoflow - see
www.geoflow.com or the impregnated filter by Netafim (they have a website
which you will easily find).
Rodney Ruskin
rr@geoflow.com
------------------------------
Date: Thu, 18 Sep 1997 00:41:28 -0400
From: Fermin Perez (FPrez0640@AOL.COM)
Subject: Re: Porous pipe made from recycled tires
I am glad to see the responses to the porous pipe question.
I wouldn't even put it in a lawn. What a waste of money.
I am glad you are enjoying your retirement. Why don't you buy a plane?
There are golf courses all over the U.S.
Fermin
------------------------------
End of TRICKLE-L Digest - 16 Sep 1997 to 17 Sep 1997
****************************************************
Date: Tue, 23 Sep 1997 00:02:36 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 17 Sep 1997 to 22 Sep 1997
There are 5 messages totalling 308 lines in this issue.
Topics of the day:
1. subsurface laterals - how deep?
2. Depth of SDI laterals - how deep? Reply from F. Lamm (3)
3. Algae and Scale elimination in Irrigation
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Mon, 22 Sep 1997 14:15:30 -0700
From: Jochen Eberhard (Jochen.Eberhard@T-ONLINE.DE)
Subject: subsurface laterals - how deep?
Hi trickle-l members,
I need your experiences. To make a multiseasonal subsurface installation
successful it is essential to bury the tape as deep as possible to have
the chance to drive on the field with heavy machinery and do some kind
of tillage. But if the laterals are to deep, one has a hard time to
establish a crop. What are the limits in both directions. Are there
differences in the type of soil? I tried a few meters with tape 15
inches deep (35cm) on a sandy loam and it was not possible to establish
transplanted lettuce under sunny and hot weather conditions. So I would
have to use overhead irrigation for the first one or two weeks. But I do
not like the idea to have two irrigationsystems in the field.
It would be very kind if I could participate on your experience
Best regards
Jochen Eberhard
_____________________________________________________________
| Jochen Eberhard * * |
| SLFA Versuchsbetriebe ( \ / ) |
| Queckbrunnerhof \ / |
| Dannstadter Str. 91 --- |
| 67105 Schifferstadt (o|o) |
| Germany ( ~~~ ) |
| ( ) |
| Tel: 0049 - 6235 - 2672 ( ) |
| Fax: - - 82741 ( ooO Ooo ) |
| email: Jochen.Eberhard@t-online.de |
|_____________________________________________________________|
------------------------------
Date: Mon, 22 Sep 1997 09:41:30 -0500
From: Freddie Lamm (FLamm@OZNET.KSU.EDU)
Subject: Depth of SDI laterals - how deep? Reply from F. Lamm
Jochen.Eberhard said (edited for brevity):
To make a multiseasonal subsurface installation
successful it is essential to bury the tape as deep as possible to have
the chance to drive on the field with heavy machinery and do some kind
of tillage. But if the laterals are to deep, one has a hard time to
establish a crop. What are the limits in both directions. Are there
differences in the type of soil?
Freddie Lamm replied: Jochen, there is no set depth that works for
all cases. It will be depend on soil and crop, which you already
have stated. If you have a row crop, you might try limiting tillage
and traffic to zones that do not include the tape (ie. Don't drive
over dripline, Till to the sides and above dripline.)
Here is the standard answer, I give to your often asked question. The specifics
of each case, would require modifications to it.
STANDARD ANSWER:
The installation depth is also related to the crop and soil type.
Deep installations reduce the potential for soil evaporation and also
allow for a wider range of tillage practices. However, deep
installations may limit the effectiveness of the SDI system for
germination and may restrict availability of surface-applied
nutrients. Acceptable results have been obtained with depths of
approximately 18 inches in KSU corn irrigation studies in western
Kansas on deep silt loam soils. Dripline probably should be installed above any
restrictive clay layers that might exist in the soil. This would help
increase lateral soil water redistribution.
Freddie
*
Best regards
Jochen Eberhard
_____________________________________________________________
| Jochen Eberhard * * |
| SLFA Versuchsbetriebe ( \ / ) |
| Queckbrunnerhof \ / |
| Dannstadter Str. 91 --- |
| 67105 Schifferstadt (o|o) |
| Germany ( ~~~ ) |
| ( ) |
| Tel: 0049 - 6235 - 2672 ( ) |
| Fax: - - 82741 ( ooO Ooo ) |
| email: Jochen.Eberhard@t-online.de |
|_____________________________________________________________|
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
-------------------------------------------------------------------
Freddie Lamm *
Research Agricultural Engineer *** o
KSU Northwest Research-Extension Center ***** /|\
105 Experiment Farm Road *******\\
Colby, Kansas 67701-1697 *********
Ph. 785-462-6281 ***********
FAX 785-462-2315 *************
Email:flamm@oznet.ksu.edu It's all downhill from here.
------ THERE'S NO DOMAIN LIKE OZ, THERE'S NO DOMAIN LIKE OZ. -------
------------------------------
Date: Mon, 22 Sep 1997 13:13:09 -0400
From: Drip tape (Driptape@AOL.COM)
Subject: Re: Depth of SDI laterals - how deep? Reply from F. Lamm
TRY A DEEP ROOTED CROP YEAR ONE AND A SHALLOW ROOTED CROP FOR THE 2ND YEAR.
IF PLASTIC MULCH IS USED CUT STALKS AND PULL UP PLASTIC THEN REFORN BED FOR
2ND CROP. HOWEVER, THERE IS NO SET RULE AS PREVIOUSLY STATED.. SOIL
CONDITIONS AND CROP ARE CRITERIA TO BE ADDED TO WITH OTHER VARIABLES.
------------------------------
Date: Mon, 22 Sep 1997 15:19:37 -0400
From: Norris Powell (nlpow@VT.EDU)
Subject: Re: Depth of SDI laterals - how deep? Reply from F. Lamm
Try the Arizona Drip Systems,Inc. For information contact:
Patrick Fernandes or
Charles R. Schultz
3227 W. Bechtel Road
Coolidge, Arizona 85228
Phone (520) 723-9226
Fax (520) 723-9210
Norris L. Powell
At 01:13 PM 9/22/97 -0400, you wrote:
)TRY A DEEP ROOTED CROP YEAR ONE AND A SHALLOW ROOTED CROP FOR THE 2ND YEAR.
)IF PLASTIC MULCH IS USED CUT STALKS AND PULL UP PLASTIC THEN REFORN BED FOR
)2ND CROP. HOWEVER, THERE IS NO SET RULE AS PREVIOUSLY STATED.. SOIL
)CONDITIONS AND CROP ARE CRITERIA TO BE ADDED TO WITH OTHER VARIABLES.
)
) ##############################################################
)Attention list subscribers! Please DO NOT send any attached files (graphics
)or text documents) to the Trickle-L list. If experiencing any problems
)obtaining Trickle-L information, please contact the list owner, Richard
)Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
Norris L. Powell
Crop and Soil Environmental Sciences
Virginia Polytechnic Institute and State University
Tidewater Agricultural Research and Extension Center
6321 Holland Road
Suffolk, VA 23437
757-657-6450 ext 112
FAX: 757-657-9333
------------------------------
Date: Sun, 21 Sep 1997 23:06:55 -0400
From: Frank H (suemc@GATE.NET)
Subject: Algae and Scale elimination in Irrigation
Algae and scale in irrigation can be eliminated by several methods
but it is helpful to have at least a cursory understanding of the
underlying mechanism of particles in suspension.
In any water based solution, the formation of algae and scale is a
physical chemistry (surface charge) problem not an ionic one. Inorganic
materials and proteins are held in suspension in water by the repulsive
force of a small electro-negative charge on the microscopic particles.
(generally less than 1 micron and called colloids)
While every situation will differ, some rough values are as follows:
0 to -15 millivolts Powerful agglomeration, coagulation and
precipitation
-15 to -30 millivolts Area of gentle dispersion
-30 to - 40 mv. moderate stability
--40 to -60mv. good stability
above - 60 excellent stability.
Water with a particle charge of -60mv is able to carry a larger number
of particles in suspension without precipitation or clumping. As the
charge reduces toward -15 to -30mv., the small particles in suspension
will begin clump together and the heavier materials will begin to
settle out. Algae and scale form from this clumping of small of
particles into large.
Chemical Remedy
Take a sample of the water to a colloidal chemistry firm or to the
physical science departmant of your local university. Have the surface
charge measured.
They should be able to recommend a colloid which can be added to the
water to increase the charge. Generally a very small amount of a
material with three or four negative electrons such as potassium citrate
will stabilize the suspension.
)From Lab to Field.
In the field, there are several factors which affect the surface
charge.
1. Aeration will reduce the charge as the .3% carbon dioxide in air will
lower the pH. Lower pH = lower charge. Increasing pH by the addition of
lime will work but is a poor alternative as the lime adds more dissolved
solids to the solution. No matter how stable any suspension is, there
is a point where it will not carry any more material. The water becomes
supersaturated and the charge on the particles is destroyed. ( Bulk
Stress)
2. AC electromagnetic radiation particularly 60 cycle reduces the
charge.
3. Excessive salts will "salt out" the suspension completely.
4. Aluminum has three positive electrons and is used in drinking water
to destroy the charge so material in suspension will settle out and the
water will be clear. Any tri valent cation will destroy Zeta potential
and cause algae formation. As an aside; in home air conditioning, the
aluminum drip pan is the cause of the algae formation and clogging of
the drain. Paint or line the pan and the problem disappears.
Non Ionic Remedies- Water Ionization
There are a number of devices for artificial ionization of water.
Because the method of action has not been understood, the effects have
been inconsistent. The amount of charge needed is a function of initial
surface charge, flow rates, pipe size and length of run.
Without understanding the method of action, there was not a way to
calculate how much charge was needed. That mechanism now exists and
there are good guidelines for electrostatics. The results can be
achieved consistently with the right equipment at a very low operating
cost.
Ancillary benefits from increase in surface charge
Normally the surface tension of water is about 75 dynes/cm. Increasing
the surface charge on particles in suspension reduces the surface
tension to around 58. This is the surface tension of boiling water.. The
dissolving power of irrigation water at room temperature becomes that of
boiling water. Less water is needed and more nutrients are freed from
the soil to become available to the plant. The water can carry them to
the plant because of the increased charge.. Feeding is reduced.
Disadvantage
Clogging of heads will initially be a problem. The scale and algae in
the system is going to go back into suspension and may break loose from
pipe walls. in larger pieces. Flushing mitigates this. Once the system
cleans up, this is no longer a problem.
Baseline Field measurements
It is both too time consuming and impractical to retest for surface
charge in a lab whenever a change occurs. From a practical standpoint,
field monitoring can be done as follows:
Purchase a large glass U tube ann two platinum electrodes from a
chemical supply house and get a 100 volt or higher Dc power supply.( Low
amperage) Place the water in the tube with an electrode on each side.
When energized, the water on the negative pole side of the U tube will
rise. The difference in height between the positive electrode side and
the negative is a measure of the surface charge on particles in
solution. If the U tube is filled to the same level each time, you can
measure whether the charge has increased or decreased. Use the initial
lab results as a baseline. To test for the effect of an addition of any
material to the feeding, add it to the water sample and check the change
in water height. This is only necessary on chemical changes.
Ionization with the right equipment is not as sensitive.
For many, this will be a totally new and confusing model and this is a
very cursory, simplified look at a complicated subject. The underlying
principles are simple and elegant. Occams Razor stuff !
There is no magic or mystery here. These principles are well proven
science. only the application has not been understood. It is not
necessary to understand this for it to work. This is intened to be a
practical rather than theoretical explantion.
For those who wish to understand the principles and their
application better but are not ready to back for a complete course in
colloidal chemistry, the following are recommended:
Zeta Potential- the complete course in 5 minutes sales@zetameter.com
free brochure.
Control of colloidal Stability through Zeta Potential - seminal work in
the field by Thomas Riddick. Now out of print but available in almost
any college library or on interlibrary loan.
Introduction to colloidal Chemistry. Mysels-Interscience-Wiley
Non Ionic Surfactants- Martin J Schick -Marcel Dekker
These are all older texts on practical understanding and application of
the principles. The newer texts are caught up in the esoteric nuances of
the profession.
For specific applications : email the following information: pump size
in gpm longest run, water source, If a well; depth of well and simple
description of the system.
------------------------------
End of TRICKLE-L Digest - 17 Sep 1997 to 22 Sep 1997
****************************************************
Date: Wed, 24 Sep 1997 00:01:50 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 22 Sep 1997 to 23 Sep 1997
There are 3 messages totalling 282 lines in this issue.
Topics of the day:
1. mail failed, returning to sender (2)
2. Algae and Scale elimination in Irrigation
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Tue, 23 Sep 1997 18:09:37 +0000
From: Brian Peadon (irrigate@LISP.COM.AU)
Subject: mail failed, returning to sender
|------------------------- Message log follows: -------------------------|
no valid recipients were found for this message
|------------------------- Failed addresses follow: ---------------------|
(Jochen.Eberhar@T-ONLINE.DE) ... unknown user
|------------------------- Message text follows: ------------------------|
Received: from sunny.lisp.com.au ([203.21.133.1]) by mailin02.btx.dtag.de with
smtp (S3.1.29.1) id (m0xDJIY-000CVbC); Tue, 23 Sep 97 02:57 MET DST
Received: from lisp.lisp.com.au (lisp-ip72.lisp.com.au [203.21.133.72])
by sunny.lisp.com.au (8.8.7/1.0CNS) with SMTP
id LAA28802 for (Jochen.Eberhar@T-ONLINE.DE); Tue, 23 Sep 1997 11:00:20 +1000 (EST)
Message-Id: (199709230100.LAA28802@sunny.lisp.com.au)
Comments: Authenticated sender is (irrigate@lisp.com.au)
From: "Brian Peadon" (irrigate@lisp.com.au)
To: Jochen.Eberhar@T-ONLINE.DE
Date: Tue, 23 Sep 1997 11:00:15 +0000
Content-type: text/plain; charset=US-ASCII
Content-transfer-encoding: 7BIT
Subject: Re: subsurface laterals - how deep?
Reply-to: irrigate@lisp.com.au
Priority: normal
In-reply-to: (3426DFF2.4006@t-online.de)
X-mailer: Pegasus Mail for Win32 (v2.54)
) Date: Mon, 22 Sep 1997 14:15:30 -0700
) From: Jochen Eberhard (Jochen.Eberhard@T-ONLINE.DE)
) Subject: subsurface laterals - how deep?
) To: TRICKLE-L@crcvms.unl.edu
) Reply-to: Jochen.Eberhar@T-ONLINE.DE
) Organization: SLFA Neustadt, Versuchsbetrieb
) Hi trickle-l members,
)
) I need your experiences. To make a multiseasonal subsurface installation
) successful it is essential to bury the tape as deep as possible to have
) the chance to drive on the field with heavy machinery and do some kind
) of tillage. But if the laterals are to deep, one has a hard time to
) establish a crop. What are the limits in both directions. Are there
) differences in the type of soil? I tried a few meters with tape 15
) inches deep (35cm) on a sandy loam and it was not possible to establish
) transplanted lettuce under sunny and hot weather conditions. So I would
) have to use overhead irrigation for the first one or two weeks. But I do
) not like the idea to have two irrigationsystems in the field.
) It would be very kind if I could participate on your experience
)
) Best regards
) Jochen Eberhard
)
) _____________________________________________________________
) | Jochen Eberhard * * |
) | SLFA Versuchsbetriebe ( \ / ) |
) | Queckbrunnerhof \ / |
) | Dannstadter Str. 91 --- |
) | 67105 Schifferstadt (o|o) |
) | Germany ( ~~~ ) |
) | ( ) |
) | Tel: 0049 - 6235 - 2672 ( ) |
) | Fax: - - 82741 ( ooO Ooo ) |
) | email: Jochen.Eberhard@t-online.de |
) |_____________________________________________________________|
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files (graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
)
We bury 8 to 10" in row crop situations, depending on soil type.
Initially we had problems germinating using conventional insertion
techniques.
The technique we use now is to form furrows as you would for a
surface system. We lay the tape down between every second furrow on
the surface,( or just below) then irrigate lightly. On one more pass
the furrows are collapsed and a bed formed on top of the tape. Subing
up irrigation is then carried out. The tape is now 10" under the bed
surface and it probably takes half the time to close out the beds,
with uniform surface wetting.
Regards,
Brian Peadon
------------------------------
Date: Tue, 23 Sep 1997 08:48:18 -0400
From: Al Shields (shieldsa@ANDREWS.EDU)
Subject: Re: mail failed, returning to sender
Brian Peadon wrote:
) Message-Id: (199709230100.LAA28802@sunny.lisp.com.au)
) Comments: Authenticated sender is (irrigate@lisp.com.au)
) From: "Brian Peadon" (irrigate@lisp.com.au)
) To: Jochen.Eberhar@T-ONLINE.DE
) Date: Tue, 23 Sep 1997 11:00:15 +0000
)
) Subject: Re: subsurface laterals - how deep?
) Reply-to: irrigate@lisp.com.au
) Priority: normal
) ) ##############################################################
) )
)
) We bury 8 to 10" in row crop situations, depending on soil type.
) Initially we had problems germinating using conventional insertion
) techniques.
)
) The technique we use now is to form furrows as you would for a
) surface system. We lay the tape down between every second furrow on
) the surface,( or just below) then irrigate lightly. On one more pass
) the furrows are collapsed and a bed formed on top of the tape. Subing
) up irrigation is then carried out. The tape is now 10" under the bed
) surface and it probably takes half the time to close out the beds,
) with uniform surface wetting.
)
) Regards,
) Brian Peadon
)
Can you detail the tape flow rate, spacing, etc that you use and the total flow volume needed to
sub up after furrow closing?
Al Shields
------------------------------
Date: Mon, 22 Sep 1997 20:43:11 -0400
From: Frank H (suemc@GATE.NET)
Subject: Algae and Scale elimination in Irrigation
Algae and scale in irrigation can be eliminated by several methods
but it is helpful to have at least a cursory understanding of the
underlying mechanism of particles in suspension.
In any water based solution, the formation of algae and scale is a
physical chemistry (surface charge) problem not an ionic one.
Microscopic particles of inorganic materials and proteins are held in
suspension by the repulsive
force of a small electro-negative charge on the particles. These
particles are generally less than 1 micon and are called colloids.
While every situation will differ, some rough values are as follows:
0 to -15 millivolts Powerful agglomeration, coagulation and
precipitation
-15 to -30 millivolts Area of gentle dispersion
-30 to - 40 mv. moderate stability
--40 to -60mv. good stability
above - 60 excellent stability.
Water with a particle charge of -60mv is able to carry a larger number
of particles in suspension without precipitation or clumping. As the
charge reduces toward -15 to -30mv., the small particles in suspension
will begin clump together and the heavier materials will begin to
settle out. Algae and scale form from this clumping of small of
particles into large.
Chemical Remedy for low stabilty creating algae and scaling
Take a sample of the water to a colloidal chemistry firm or to the
physical science departmant of your local university. Have the surface
charge measured.
They should be able to recommend a colloid which can be added to the
water to increase the charge. Generally a very small amount of a
material with three or four negative electrons such as potassium citrate
will stabilize the suspension.
)From Lab to Field.
In the field, there are several factors which affect the surface
charge.
1. Aeration will reduce the charge as the .3% carbon dioxide in air will
lower the pH. Lower pH = lower charge. Increasing pH by the addition of
lime will work but is a poor alternative as the lime adds more dissolved
solids to the solution. No matter how stable any suspension is, there
is a point where it will not carry any more material. The water becomes
supersaturated and the charge on the particles is destroyed. ( Bulk
Stress)
2. AC electromagnetic radiation particularly 60 cycle reduces the
charge.
3. Excessive salts will "salt out" the suspension completely.
4. Aluminum has three positive electrons and is used in drinking water
to destroy the charge so material in suspension will settle out and the
water will be clear. Any tri valent cation will destroy the charge on a
colloid
and cause algae and/or scale formation.
Non Ionic Remedies- Water Ionization
There are a number of devices for artificial ionization of water.
Because the method of action has not been understood, the effects have
been inconsistent. The amount of charge needed is a function of initial
surface charge, flow rates, pipe size and length of run.
Without understanding the method of action, there was not a way to
calculate how much charge was needed. That mechanism now exists and
there are good guidelines for electrostatics. The results can be
achieved consistently with the right equipment at a very low operating
cost.
Ancillary benefits from increase in surface charge
Normally the surface tension of water is about 75 dynes/cm. Increasing
the surface charge on particles in suspension reduces the surface
tension to around 58. This is the surface tension of boiling water.. The
dissolving power of irrigation water at room temperature becomes that of
boiling water. Less water is needed and more nutrients are freed from
the soil to become available to the plant. The water can carry them to
the plant because of the increased charge.. Feeding is reduced.
Initial Challenges/?Disadvantages
Clogging of heads will initially be a problem. The scale and algae in
the system is going to go back into suspension and may break loose from
pipe walls. in larger pieces. Flushing mitigates this. Once the system
cleans up, this is no longer a problem.
Baseline Field measurements
It is both too time consuming and impractical to retest for surface
charge in a lab whenever a change occurs. From a practical standpoint,
field monitoring can be done as follows:
Purchase a large glass U tube ann two platinum electrodes from a
chemical supply house and get a 100 volt or higher Dc power supply.( Low
amperage) Place the water in the tube with an electrode on each side.
When energized, the water on the negative pole side of the U tube will
rise. The difference in height between the positive electrode side and
the negative is a measure of the surface charge on particles in
solution. If the U tube is filled to the same level each time, you can
measure whether the charge has increased or decreased. Use the initial
lab results as a baseline. To test for the effect of an addition of any
material to the feeding, add it to the water sample and check the change
in water height. This is only necessary on chemical changes.
Ionization with the right equipment is not as sensitive.
For many, this will be a totally new model and is a very
cursory,simplified look at a subject that initially seems very
complicated. The principles are simple and the mechanism clear once we
recognize that this is a different way of viewing the problem. Another
tool ! "When the only tool you have is a hammer,
every problem begins to look like a nail".
There is no magic or mystery here. These principles are well proven
science. only the application has not been understood. It is not
necessary to understand this for it to work and this is intended to be
more
practical rather than theoretical.
For those who wish to understand the principles and their
application better but are not ready to back for a complete course in
colloidal chemistry, the following are recommended:
Zeta Potential- the complete course in 5 minutes sales@zetameter.com
free brochure.
Control of colloidal Stability through Zeta Potential - seminal work in
the field by Thomas Riddick. Now out of print but available in almost
any college library or on interlibrary loan.
Introduction to colloidal Chemistry. Mysels-Interscience-Wiley
Non Ionic Surfactants- Martin J Schick -Marcel Dekker
These are all older texts on practical understanding and application of
the principles. The newer texts are caught up in the esoteric nuances of
the profession.
For specific applications : email the following information: pump size
in gpm longest run, water source, If a well; depth of well and simple
description of the system.
------------------------------
End of TRICKLE-L Digest - 22 Sep 1997 to 23 Sep 1997
****************************************************
Date: Thu, 25 Sep 1997 00:02:14 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 23 Sep 1997 to 24 Sep 1997
There are 2 messages totalling 224 lines in this issue.
Topics of the day:
1. Introduction of new member
2. Algae and Scale elimination in Irrigation attn Louis Ravina
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Wed, 24 Sep 1997 07:39:37 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: Introduction of new member
Below are answers to the introductory questions for new subscribers.=20
Please welcome Carole Isb=E9rie.
p.s.
Carole, your English is by far better than my French :-)
RMM
Trickle-L owner
--------------------------------------
)WELCOME NEW MEMBER!!
Dear Richard M. Mead
Thank you for welcome me. Here are my answers. Excuse me for my bad
english, I hope it is nevertheless understandable.
)-----
)1) Briefly, what is your affiliation with trickle/drip irrigation?
I am agronomist, researcher in Cemagref (french research institut), and
have led experimentations about irrigation water requirements with drip
irrigation.
)2) What crops or plants do you use drip irrigation on?
orchards and vine.
)3) If using subsurface drip irrigation, what is the average depth of
)placement of the drip lateral?
I haven't used it
)4) What problems have you encountered with drip irrigation?
In France irrigation is the complement of the naturally disponible water
(from soil reserve or rain).
This amount of water cannot be good estimated with only hydric balance
methods. So it is necessary to use measurements (in my case tensiometers)
to schedule irrigation and to minimize irrigation water, without harming
orchard and yield.
We work too to develop this scheduling method for farmers.
)5) Fertigation is a real advantage of drip irrigation. What form of N, P
)and K have you been trying and to what success?
I cannot answer
)6) Have you experienced a reduction in fertilizer and/or water use?
see question 4 above
)7) Do you have water quality problems? If so, how do you tackle the
situation?
yes, we have had. It was necessary to clean the system with acid.
)8) How frequent do you irrigate? Many times a day, one long session per
)day, or once every several days?
If manually tensiometric measurements, usually one session per day.
If automatically, it can be many times a day.
)9) Do you have rodent damage? If so, how do you control the problem?
/
)10) Are you pleased with the uniformity of your system or systems? Were
)they designed correctly?
/
)11) How did you find out about the Trickle-L mailing list?
Yesterday, in "Zeitshrift f=FCr Bew=E4sserungswirtschaft" 1/97 (=3DJ. =
Appl.
Irrig. Sci.)
Before P. Revol of Cemagref Grenoble had told me about it, but I haven't
noted adress.
Best regards
Carole Isb=E9rie
Carole ISBERIE
Cemagref
Division OIAX, Equipe Irrigation
Le Tholonet
B.P. 31
13612 AIX-EN-PROVENCE CEDEX 1
tel.: +33 (0)4 42 66 99 44
fax : +33 (0)4 42 66 88 65
e-mail : carole.isberie@cemagref.fr
------------------------------
Date: Tue, 23 Sep 1997 15:31:59 -0400
From: Frank H (suemc@GATE.NET)
Subject: Algae and Scale elimination in Irrigation attn Louis Ravina
Algae and scale in irrigation can be eliminated by several methods
but it is helpful to have at least a cursory understanding of the
underlying mechanism of particles in suspension.
In any water based solution, the formation of algae and scale is a
physical chemistry (surface charge) problem not an ionic one.
Microscopic particles of inorganic materials and proteins are held in
suspension by the repulsive force of a small electro-negative charge on
the particles. These particles are generally less than 1 micon and are
called colloids.
While every situation will differ, some rough values are as follows:
0 to -15 millivolts Powerful agglomeration, coagulation and
precipitation
-15 to -30 millivolts Area of gentle dispersion
-30 to - 40 mv. moderate stability
--40 to -60mv. good stability
above - 60 excellent stability.
Water with a particle charge of -60mv is able to carry a larger number
of particles in suspension without precipitation or clumping. As the
charge reduces toward -15 to -30mv., the small particles in suspension
will begin clump together and the heavier materials will begin to
settle out. Algae and scale form from this clumping of small of
particles into large.
Chemical Remedy for low stabilty creating algae and scaling
Take a sample of the water to a colloidal chemistry firm or to the
physical science departmant of your local university. Have the surface
charge measured.
They should be able to recommend a colloid which can be added to the
water to increase the charge. The solution may only need a small amount
of a material with three or four negative electrons such as potassium
citrate to stabilize the suspension.
)From Lab to Field.
In the field, there are several factors which affect the surface
charge.
1. Aeration will reduce the charge as the .3% carbon dioxide in air will
lower the pH. Lower pH = lower charge. Increasing pH by the addition of
lime will work but is a poor alternative as the lime adds more dissolved
solids to the solution. No matter how stable any suspension is, there
is a point where it will not carry any more material. The water becomes
supersaturated and the charge on the particles is destroyed. ( Bulk
Stress)
2. AC electromagnetic radiation particularly 60 cycle reduces the
charge.
3. Excessive salts will "salt out" the suspension completely.
4. Aluminum has three positive electrons and is used in drinking water
to destroy the charge so material in suspension will settle out and the
water will be clear. Cations will reduce the charge; A divalent cation
has a 3000 times more powerful effect than a substance with a single
posive ion. A trivalent cation like aluminum is 6000 times more powerful
than a single cation. Any tri valent cation will destroy the charge on
a colloid and cause algae and/or scale formation.
Non Ionic Remedies- Water Ionization
There are a number of devices for artificial ionization of water.
Because the method of action has not been understood, the effects have
been inconsistent. The amount of charge needed is a function of initial
surface charge, flow rates, pipe size and length of run.
Without understanding the method of action, there was not a way to
calculate how much charge was needed. That mechanism now exists and
there are good guidelines for electrostatics. The results can be
achieved consistently with the right equipment at a very low operating
cost.
Ancillary benefits from increase in surface charge
Normally the surface tension of water is about 75 dynes/cm. Increasing
the surface charge on particles in suspension reduces the surface
tension to around 58. This is near the surface tension of boiling
water.. The dissolving power of irrigation water at room temperature
becomes that of boiling water. Less water is needed and more nutrients
are freed from the soil to become available to the plant. The water can
carry them to the plant because of the increased charge.. Feeding is
reduced.
Initial Challenges/?Disadvantages
Clogging of heads will initially be a problem. The scale and algae in
the system is going to go back into suspension and may break loose from
pipe walls. in larger pieces. Flushing mitigates this. Once the system
cleans up, this is no longer a problem.
Baseline Field measurements
It is both too time consuming and impractical to retest for surface
charge in a lab whenever a change occurs. From a practical standpoint,
field monitoring can be done as follows:
Purchase a large glass U tube ann two platinum electrodes from a
chemical supply house and get a 100 volt or higher Dc power supply.( Low
amperage) Place the water in the tube with an electrode on each side.
The difference in height between the positive electrode side and
the negative is a measure of the surface charge on particles in
solution. If the U tube is filled to the same level each time, you can
measure whether the charge has increased or decreased. Use the initial
lab results as a baseline. To test for the effect of an addition of any
material to the feeding, add it to the water sample and check the change
in water height. This is only necessary on chemical changes.
Ionization with the right equipment is not as sensitive.
For many, this will be a totally new model and is a very
cursory,simplified look at a subject that initially seems very
complicated. The principles are simple and the mechanism clear once we
recognize that this is a different way of viewing the problem. Another
tool ! "When the only tool you have is a hammer, every problem begins
to look like a nail".
There is no magic or mystery here. These principles are well proven
science. only the application has not been understood. It is not
necessary to understand this for it to work and this is intended to be
more practical rather than theoretical.
For those who wish to understand the principles and their
application better but are not ready to back for a complete course in
colloidal chemistry, the following are recommended:
Zeta Potential- The complete course in 5 minutes. info@zeta-meter.com
free brochure.
Control of colloidal Stability through Zeta Potential - seminal work in
the field by Thomas Riddick. Now out of print but available in almost
any college library or on interlibrary loan.
Introduction to colloidal Chemistry. Mysels-Interscience-Wiley
Non Ionic Surfactants- Martin J Schick -Marcel Dekker
These are all older texts on practical understanding and application of
the principles. The newer texts are caught up in the esoteric nuances of
the profession.
specific applications: e mail author
------------------------------
End of TRICKLE-L Digest - 23 Sep 1997 to 24 Sep 1997
****************************************************
Date: Fri, 26 Sep 1997 00:02:32 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 24 Sep 1997 to 25 Sep 1997
There are 6 messages totalling 353 lines in this issue.
Topics of the day:
1. Algae and Scale elimination in Irrigation attn Louis Ravina
2. A.D.I
3. lateral depth (3)
4. lateral depth, FR Lamm comment 2
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Thu, 25 Sep 1997 12:56:38 +0200
From: amirim (amirim@INTER.NET.IL)
Subject: Re: Algae and Scale elimination in Irrigation attn Louis Ravina
Frank H wrote:
)
) Algae and scale in irrigation can be eliminated by several methods
) but it is helpful to have at least a cursory understanding of the
) underlying mechanism of particles in suspension.
)
) In any water based solution, the formation of algae and scale is a
) physical chemistry (surface charge) problem not an ionic one.
) Microscopic particles of inorganic materials and proteins are held in
) suspension by the repulsive force of a small electro-negative charge on
) the particles. These particles are generally less than 1 micon and are
) called colloids.
)
) While every situation will differ, some rough values are as follows:
) 0 to -15 millivolts Powerful agglomeration, coagulation and
) precipitation
) -15 to -30 millivolts Area of gentle dispersion
) -30 to - 40 mv. moderate stability
) --40 to -60mv. good stability
) above - 60 excellent stability.
)
) Water with a particle charge of -60mv is able to carry a larger number
) of particles in suspension without precipitation or clumping. As the
) charge reduces toward -15 to -30mv., the small particles in suspension
) will begin clump together and the heavier materials will begin to
) settle out. Algae and scale form from this clumping of small of
) particles into large.
)
) Chemical Remedy for low stabilty creating algae and scaling
) Take a sample of the water to a colloidal chemistry firm or to the
) physical science departmant of your local university. Have the surface
) charge measured.
) They should be able to recommend a colloid which can be added to the
) water to increase the charge. The solution may only need a small amount
) of a material with three or four negative electrons such as potassium
) citrate to stabilize the suspension.
)
) )From Lab to Field.
) In the field, there are several factors which affect the surface
) charge.
)
) 1. Aeration will reduce the charge as the .3% carbon dioxide in air will
) lower the pH. Lower pH = lower charge. Increasing pH by the addition of
) lime will work but is a poor alternative as the lime adds more dissolved
) solids to the solution. No matter how stable any suspension is, there
) is a point where it will not carry any more material. The water becomes
) supersaturated and the charge on the particles is destroyed. ( Bulk
) Stress)
) 2. AC electromagnetic radiation particularly 60 cycle reduces the
) charge.
) 3. Excessive salts will "salt out" the suspension completely.
) 4. Aluminum has three positive electrons and is used in drinking water
) to destroy the charge so material in suspension will settle out and the
) water will be clear. Cations will reduce the charge; A divalent cation
) has a 3000 times more powerful effect than a substance with a single
) posive ion. A trivalent cation like aluminum is 6000 times more powerful
) than a single cation. Any tri valent cation will destroy the charge on
) a colloid and cause algae and/or scale formation.
)
) Non Ionic Remedies- Water Ionization
) There are a number of devices for artificial ionization of water.
) Because the method of action has not been understood, the effects have
) been inconsistent. The amount of charge needed is a function of initial
) surface charge, flow rates, pipe size and length of run.
) Without understanding the method of action, there was not a way to
) calculate how much charge was needed. That mechanism now exists and
) there are good guidelines for electrostatics. The results can be
) achieved consistently with the right equipment at a very low operating
) cost.
)
) Ancillary benefits from increase in surface charge
)
) Normally the surface tension of water is about 75 dynes/cm. Increasing
) the surface charge on particles in suspension reduces the surface
) tension to around 58. This is near the surface tension of boiling
) water.. The dissolving power of irrigation water at room temperature
) becomes that of boiling water. Less water is needed and more nutrients
) are freed from the soil to become available to the plant. The water can
) carry them to the plant because of the increased charge.. Feeding is
) reduced.
)
) Initial Challenges/?Disadvantages
)
) Clogging of heads will initially be a problem. The scale and algae in
) the system is going to go back into suspension and may break loose from
) pipe walls. in larger pieces. Flushing mitigates this. Once the system
) cleans up, this is no longer a problem.
)
) Baseline Field measurements
) It is both too time consuming and impractical to retest for surface
) charge in a lab whenever a change occurs. From a practical standpoint,
) field monitoring can be done as follows:
) Purchase a large glass U tube ann two platinum electrodes from a
) chemical supply house and get a 100 volt or higher Dc power supply.( Low
) amperage) Place the water in the tube with an electrode on each side.
) The difference in height between the positive electrode side and
) the negative is a measure of the surface charge on particles in
) solution. If the U tube is filled to the same level each time, you can
) measure whether the charge has increased or decreased. Use the initial
) lab results as a baseline. To test for the effect of an addition of any
) material to the feeding, add it to the water sample and check the change
) in water height. This is only necessary on chemical changes.
)
) Ionization with the right equipment is not as sensitive.
)
) For many, this will be a totally new model and is a very
) cursory,simplified look at a subject that initially seems very
) complicated. The principles are simple and the mechanism clear once we
) recognize that this is a different way of viewing the problem. Another
) tool ! "When the only tool you have is a hammer, every problem begins
) to look like a nail".
)
) There is no magic or mystery here. These principles are well proven
) science. only the application has not been understood. It is not
) necessary to understand this for it to work and this is intended to be
) more practical rather than theoretical.
) For those who wish to understand the principles and their
) application better but are not ready to back for a complete course in
) colloidal chemistry, the following are recommended:
)
) Zeta Potential- The complete course in 5 minutes. info@zeta-meter.com
) free brochure.
)
) Control of colloidal Stability through Zeta Potential - seminal work in
) the field by Thomas Riddick. Now out of print but available in almost
) any college library or on interlibrary loan.
)
) Introduction to colloidal Chemistry. Mysels-Interscience-Wiley
)
) Non Ionic Surfactants- Martin J Schick -Marcel Dekker
)
) These are all older texts on practical understanding and application of
) the principles. The newer texts are caught up in the esoteric nuances of
) the profession.
)
) specific applications: e mail author
)
) ##############################################################
) Attention list subscribers! Please DO NOT send any attached files (graphics
) or text documents) to the Trickle-L list. If experiencing any problems
) obtaining Trickle-L information, please contact the list owner, Richard
) Mead (rmead@agrilink-int.com) and not the Trickle-L group.
) ##############################################################
ccccccccccccccccccccccccc
------------------------------
Date: Thu, 25 Sep 1997 13:40:25 +0200
From: amirim (amirim@INTER.NET.IL)
Subject: Re: A.D.I
amirim wrote:
)
) subject; trickle-l 3.9.97; new emitter technology
)
) let me introduce myself
) I am the inventor of the A.D.I dripper (us patent 5400973), and now
) working with
) Lego and Metzerplas.
)
) I will try to answer your questions but please forgive me for my
) english.
)
) The A.D.I compensation dripper is based on new regulation principles.
) the pressure compensationof the new dripper is achieved by varying the
) effective
) length of the regulated labyrinth.
) the larger the pressure, the longer the effective length of the
) labyrinth.
)
) this is achieved by a clearances between a membrane and a labyrinth,this
) clearances are sequentially
) closed with the increasing of thepresure and maintain a uniform flow.
)
) advantage of the technology:
)
) *large water passages
) *critical water passages remain large and permanent at high pressure.
) *trubulent flow also in the regulated zone.
) *almost flat curve at a pressure range 0.6-4.5 at.
) *trubalen flushing of all water passages.
) *self cleaning
)
) advantage in the field:
)
) *good resistance to clogging.
) *fast entry to compensation mode.
) *steady flow during the all irrigation cycle
) *highest discharge uniformity.
)
) for more information you can contact LEGO and METZERPLAS , the owners of
) the exlusive right
) or me.
)
) Amir cohen.
------------------------------
Date: Thu, 25 Sep 1997 16:49:38 -0700
From: Jochen Eberhard (Jochen.Eberhard@T-ONLINE.DE)
Subject: lateral depth
Hallo,
thanks for the comments about my question about the optimum depth of
laterals in subsurfaces drip. So if I understood it right that laterals
around 18 inch deep will not be affected by normal agricultural traffic.
As this is to deep for transplanted vegetables but what about 12 to 15
inch. This is the distance water comes up in our soil. Can anybody tell
me yes or no it is possible to drive accross the laterals without
damageing the tape. We do not yet have the equippement to try it ourself
and to avoid the big mistakes prior installation I want to participate
on your experience. Thanks again for any help
Best regards
Jochen
--
_____________________________________________________________
| Jochen Eberhard * * |
| SLFA Versuchsbetriebe ( \ / ) |
| Queckbrunnerhof \ / |
| Dannstadter Str. 91 --- |
| 67105 Schifferstadt (o|o) |
| Germany ( ~~~ ) |
| ( ) |
| Tel: 0049 - 6235 - 2672 ( ) |
| Fax: - - 82741 ( ooO Ooo ) |
| email: Jochen.Eberhard@t-online.de |
|_____________________________________________________________|
------------------------------
Date: Thu, 25 Sep 1997 13:41:33 -0500
From: "W. Bryan Smith" (wsmth@CLEMSON.EDU)
Subject: Re: lateral depth
) but what about 12 to 15
) inch. This is the distance water comes up in our soil. Can anybody tell
) me yes or no it is possible to drive accross the laterals without
) damageing the tape.
Jochen,
We have row crops here (cotton) with lateral 12" deep. So far no
problems after a few years. The farmer I am thinking about is
careful with his tillage and apparently hasn't damaged the tape yet.
Hope this helps - I'm sure the folks in the Midwest USA have more
info and experience with this.
Bryan
=|===|===|===|===|===|===|===|===|===|===|=
W. Bryan Smith
Area Extension Agent - Irrigation / Water Quality
Clemson Extension Service
P.O. Box 160, Newberry, South Carolina 29108 USA
Office: 803 276-1091 FAX: 803 276-1095
Internet: wsmth@clemson.edu
=|===|===|===|===|===|===|===|===|===|===|=
All opinions are my own and not reflective of the
policies of Clemson University or the Cooperative
Extension Service.
------------------------------
Date: Thu, 25 Sep 1997 21:41:42 -0700
From: Matej Knapic (matej.knapic@UNI-LJ.SI)
Subject: Re: lateral depth
Hi,
In my short two years experience I can say that is unlike to damage the
laterals with normal cultivation and effective planning. You should only
know how deep you will cultivate in the future and install the laterals
bellow that level. Safety distance between cultivation and laterals
depends how exact you will install the laterals. If you have rocky or
heavy gravely soil you can expect that you won't be able to install the
tape on exact desire depth. You should expect variation of laterals
depth +- 5 cm or even more. I installed the subsurface system in hops at
aprox. 30 to 35 cm depth and so far I didn't have any damage.
If you have an extremely gravely or rocky soil you should increase inlet
pressure to avoid compression of laterals at the end of the long lines.
Best regards
Matej Knapic
------------------------------
Date: Thu, 25 Sep 1997 13:29:28 -0500
From: Freddie Lamm (FLamm@OZNET.KSU.EDU)
Subject: Re: lateral depth, FR Lamm comment 2
Jochen said (edited for brevity):
..... So if I understood it right that
laterals around 18 inch deep will not be affected by normal
agricultural traffic. As this is to deep for transplanted
vegetables but what about 12 to 15 inch. This is the distance water
comes up in our soil. Can anybody tell me yes or no it is possible to
drive accross the laterals without damageing the tape.
Freddie replied: My earlier comments were that 16-18 inches has
worked for us on our soils, with our crop, with our climate, and with
our tillage schemes. It can't be safely extended to include all
cases of agricultural traffic.
Can anybody tell you yes or no for the 12-15 inch depth?? I wouldn't
dare say yes or no.
There may be some guidelines but I am unaware of any directly applicable. It
is still going to depend on soil type (I believe you said sandy),
soil water conditions, and weight of equipment and cross sectional
area of tire or track. I know there are some equations, laws and/or
rules of thumbs in soil mechanics and porous media that deal with
minimum depths for pipes in trenches, and others dealing with
compaction under agricultural tires. BUT, they may not really fit
your needs very well.
If you limit your loads on the soil (Basically pressure, kPa or psi)
and you avoid wet soils ideal for compaction, I would THINK that
12-15 depth would be sufficient, but there is no easy
one-size-fits-all answer.
Freddie
-------------------------------------------------------------------
Freddie Lamm *
Research Agricultural Engineer *** o
KSU Northwest Research-Extension Center ***** /|\
105 Experiment Farm Road *******\\
Colby, Kansas 67701-1697 *********
Ph. 785-462-6281 ***********
FAX 785-462-2315 *************
Email:flamm@oznet.ksu.edu It's all downhill from here.
------ THERE'S NO DOMAIN LIKE OZ, THERE'S NO DOMAIN LIKE OZ. -------
------------------------------
End of TRICKLE-L Digest - 24 Sep 1997 to 25 Sep 1997
****************************************************
Date: Tue, 30 Sep 1997 00:03:01 -0600
From: Automatic digest processor (LISTSERV@crcvms.unl.edu)
Subject: TRICKLE-L Digest - 25 Sep 1997 to 29 Sep 1997
There are 2 messages totalling 186 lines in this issue.
Topics of the day:
1. New member introductions
2. Soil Moisture Sensor Comparison Papers (Independent Sources)
##############################################################
Attention list subscribers! Please DO NOT send any attached files (graphics
or text documents) to the Trickle-L list. If experiencing any problems
obtaining Trickle-L information, please contact the list owner, Richard
Mead (rmead@agrilink-int.com) and not the Trickle-L group.
##############################################################
----------------------------------------------------------------------
Date: Mon, 29 Sep 1997 08:44:51 -0700
From: Richard Mead (rmead@AGRILINK-INT.COM)
Subject: New member introductions
The following info is from two new members to Trickle-L; Doug McClymont of
Zimbabwe and Julia Tien of the San Francisco Bay area.
--------------------
1) Briefly, what is your affiliation with trickle/drip irrigation?
I am a partner in a soluble fertilizer distribution company and a
consultant for drip schemes.
2) What crops or plants do you use drip irrigation on?
Virginia tobacco; paprika; tomatoes; potatoes; roses and field flowers;
onions and garlic
3) If using subsurface drip irrigation, what is the average depth of
placement of the drip lateral?
2 - 10 cm depending on crop
4) What problems have you encountered with drip irrigation?
Conservatism and price of equipment in Zimbabwe
5) Fertigation is a real advantage of drip irrigation. What form of N, P
and K have you been trying and to what success?
Very successful with all of the following depending on programme Ammonium
Nitrate; Calcium Nitrate; Potassium Nitrate; Potassium Chloride; Mono
Ammonium Phosphate; MonoPotassium Phosphate; Urea; solupotasse Potassium
Sulphate; Magnesium Nitrate Ammonium Sulphate and the Haifa (Israel) range
of soluble compounds in the "Polyfeed" Range and the Ocean Agriculture
South Africa range of Microfeeds. These ranges are quite popular because of
the added chelates and other trace elements.
6) Have you experienced a reduction in fertilizer and/or water use?
Definite reduction in water use - no reduction in fert use but improved
yields e.g. in canning tomatoes impact sprinklers 35 - 50 tonnes/ha, + drip
75 - 85 tonnes/ha, drip + soluble fert 100 -110 tonnes/ha
7) Do you have water quality problems? If so, how do you tackle the situation?
Very seldom as all our water is stored water ex rainfall (dams and
reservoirs) very few rivers and a number of boreholes. All schemes have
standard strainers of various types.
8) How frequent do you irrigate? Many times a day, one long session per
day, or once every several days?
Depends entirely on crop, stage in season and Et/Eo ratio and soil type.
Generally once every several days to start and once root "onion" is of
correct size and shape every day.
9) Do you have rodent damage? If so, how do you control the problem?
Often - perhaps you can tell me!!!!
10) Are you pleased with the uniformity of your system or systems? Were
they designed correctly?
We have a number of professional designers in the country and generally
they are pretty good - the only disasters are when the farmers do it on the
cheap - then it costs them more to put it right. Uniformity is generally
exceptional and is a continually good selling point.
11) How did you find out about the Trickle-L mailing list?
Surfing the Net.
Best wishes & Rgds
Doug McClymont
----------------------------------------------------------------------------
------------
) 1) Briefly, what is your affiliation with trickle/drip irrigation?
Home gardener in the San Francisco Bay area where the climate permits
almost year-round gardening but it doesn't rain from April until
November.
) 2) What crops or plants do you use drip irrigation on?
Small garden beds for ornamentals, lawn and veggies. The sizes are
range from 10' square to 3' x 50' to L-shaped patches about 20' wide
by 50' on each leg of the "L".
) 3) If using subsurface drip irrigation, what is the average depth of
) placement of the drip lateral?
I gave up on subsurface drip irrigation as I change my garden bed
configurations too often--I just lay the drip tubing on the surface.
) 4) What problems have you encountered with drip irrigation?
Even coverage for small lawn areas (about 500 sq ft) and odd-shaped garden
beds.
) 5) Fertigation is a real advantage of drip irrigation. What form of N, P
) and K have you been trying and to what success?
I don't fertilize via drip.
) 6) Have you experienced a reduction in fertilizer and/or water use?
Don't know--I've always used drip irrigation or soaker hoses.
) 7) Do you have water quality problems?
No.
) 8) How frequent do you irrigate? Many times a day, one long session per
) day, or once every several days?
For vegetable beds, every other day for 1-1.5 hours during the
spring/summer. For trees, lawn areas and ornamental beds, once a week
during the spring/summer for about 3 hours.
) 9) Do you have rodent damage? If so, how do you control the problem?
Occasionally squirrels chew through the tubing. I try to provide an
alternate water source (e.g., pans of water in a couple places around
the yard) so they don't resort to the drip tubing for a drink. (It's
when I forget to fill the pans that the tubing gets chomped.)
) 10) Are you pleased with the uniformity of your system or systems? Were
) they designed correctly?
No, I'm still experimenting.
Problems I'd still like to solve:
1. Shutting off sections of a system when I don't need to irrigate them--
I haven't found a good valve that I can put into a line.
2. Still looking for microsprays for use with lawn areas. My major
problem is a 3' x 50' (slightly curved) patch of lawn. Right now I
have a row of semi-circular microsprays along one side but the
coverage isn't that even. I can't put sprayers on the other side as
the driveway is there and they'll get knocked over if someone goes
off the edge.
3. Reusability and durability of system components. I find that after
3-4 years, the tubing loosens up where I have (compression)
couplers and T's, and I end up replacing the section.
4. Tubing size mismatches. I started my system with the 620mm tubing
available in local hardware centers but am eventually going to have
to yank the main line out and replace it with the slightly bigger
diameter commercial grade half-inch tubing as the fittings I want
to use only come in that size (e.g. the slip-lok screw-on
connectors).
) 11) How did you find out about the Trickle-L mailing list?
The HORTIDEAS newsletter mentioned the mailing list in their 9/97 issue.
--------------------------------------------
------------------------------
Date: Mon, 29 Sep 1997 19:32:06 -0400
From: Irrometer@AOL.COM
Subject: Soil Moisture Sensor Comparison Papers (Independent Sources)
TO: Irrigation-L and Trickle-L Members
CC: Bruce Metelerkamp--Owner SoWaCS List
I do not know his e-mail address with assurance, but I believe
that Blaine Hanson at UC Davis is a member of one of the above
lists and he has (or is preparing) a chapter for a book which will
deal with a pretty broad comparison of a variety of soil moistrure
sensing devices. There may be other such independent sources
which compare various such sensor technologies, particularly as
they may relate to a practical application of such by commercial
growers (as opposed to a pure research environment). Others who
belong to the above lists may know of these other references as
well. One item of interest here, of interest to our company as a
producer of tensiometers, is a recent bulletin put out by Kansas
State University as a part of their "IRRIGATION MANAGEMENT
SERIES", entitled "Tensiometer Use In Scheduling Irrigation". This
is one of the more comprehensive publications which I have seen
on the entire technology of tensiometer use. One of the co-authors
is Dr. Mahbub Alam (malam@oznet.ksu.edu), if anyone is interested
in taking a look at it.
In conclusion, what Bruce Metelerkamp seeks is any information
concerning any references which deal with a "comparison" of as many
soil moisture measurement technologies as possible. Thought I would
assist him by asking the independent experts who may belong to these
lists. Your can correspond directly with him at: brooz@pobox.com or
bruce.metelerkamp@pobox.com (I have yet to figure out why one e-mail
message would carry two different addresses). Thanks for your help.
Regards, Bill Pogue, President, Irrometer Company Inc.
------------------------------
End of TRICKLE-L Digest - 25 Sep 1997 to 29 Sep 1997
****************************************************
Prepared by Steve Modena, AB4EL
Suggestions and comments to: modena@SunSITE.unc.edu