This is the compendium of TRICKLE-L digests for September 1996.
It was prepared from the daily digest mailings. Some digests
may be missing, because occasional mailings are lost en route.
Contents: Re: anhydrous NH3 & micro (Jean Piaget .<.henri@ilink.nis.za.>.) <---------------------------------------------------------------------->
Date: Sat, 31 Aug 1996 22:10:05 GMT From: Jean Piaget .<.henri@ilink.nis.za.>. Subject: Re: anhydrous NH3 & micro A NO-NO, BUT I DID GET A CHUCKLE THAT >THERE IS A PUBLICATION ON REPAIRING LEAKY >PEAK WITH ANHYDROUS AMMONIA INJECTION. > > BUT WOULD BE AMUSED TO KNOW >WHAT SIZE LEAKS CAN BE REPAIRED. > ANYONE OUT THERE THAT CAN GIVE THE SPECIFICS OR >EVEN THE REASONING BEHIND THIS PUBLICATION??? > >JUST CURIOUS, AND IF IT WORKS I'M NOT >COMPLAINING. >FREDDIE >Keep at it till you get the answer, I am also wondering- But perhaps they really mean those old tyre pipes called "leaky pipe" Jean/ PS How does that fit in micro irrigation , is it not micro-plumbing? <------------------------------>
End of Digest ************************
Contents: Arkal Web Site (txgator@ct.net (Jim Brigham)) <---------------------------------------------------------------------->
Date: Mon, 2 Sep 1996 11:57:23 From: txgator@ct.net (Jim Brigham) Subject: Arkal Web Site Hello Tricklers I have not communicated with the group recently since I am no longer involved with drip irrigation. I am currently leading Arkal Water Technologies efforts to enter the industrial filtration market in the U.S. I invite you to check out our new WWW page. The address is: http://www.ct.net/~arkal By the way, I have a new e-mail address: Arkal@ct.net I've been following the threads, looks like things are moving forward in the drip industry. Jim Brigham <------------------------------>
End of Digest ************************
Contents:
topo map (Yossi Ingber .<.netafim@inter.net.il.>.)
Re: anhydrous NH3 & micro (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.)
Sealing concrete pipe & precip of lime w/ high HCO3- and NH3 ("Blake L. Sanden" .<.blsanden@ucdavis.edu.>.)
<---------------------------------------------------------------------->
Date: Tue, 03 Sep 1996 06:40:36 -0700
From: Yossi Ingber .<.netafim@inter.net.il.>.
Subject: topo map
We need for irrigation design to find a topo map on a location in
Zambia, as we deal with drip-irrigation minimum scale is 1:5000 (metric)
or better . We look for a link to a company that provides this service
based on sattelite pictures , or do you have another idea ? I searched
the internet without serious results .
Thanks / Yossi Ingber
Head of Engineering and Technical Support
Netafim-Magal / Israel
<------------------------------>
Date: Tue, 03 Sep 1996 09:07:24 -0500 (EST)
From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.
Subject: Re: anhydrous NH3 & micro
At 12:58 PM 8/28/96 -0500, you wrote:
>
>> The injection of anhydrous ammonium in water containing significant
>> calcium will form calcium carbonate scale. This is method for plugging
>> leaky pipe. Therefore, the obvious consequence for injection in micro
>> irrigation systems would be plugged emitters. There is a U.C. Davis
>> publication that describes the technique for repairing leaky pipe by
>> injecting anhydrous ammonium.
>
>
>HAVING HEARD HORROR STORIES OF IRRIGATORS
>USING ANHYDROUS AMMONIA IN CENTER PIVOT
>SPRINKLERS (IE. COLLAPSED UNITS) AND ALSO IN
>ALUMINUM GATED PIPE (IE, YOU CAN'T PICK IT UP
>AT THE END OF THE SEASON) I WAS AWARE THAT
> INJECTION INTO A PIPED WATER SUPPLY
>WAS A NO-NO, BUT I DID GET A CHUCKLE THAT
>THERE IS A PUBLICATION ON REPAIRING LEAKY
>PEAK WITH ANHYDROUS AMMONIA INJECTION.
>
>I GUESS I'M WONDERING IF THIS WAS A HOAX OR
>JOKE MESSAGE, BUT JUST IN CASE IT WASN'T,
> I'LL ***BITE***. I DON'T HAVE ANY NEED FOR THIS
>TECHNOLOGY, BUT WOULD BE AMUSED TO KNOW
>WHAT SIZE LEAKS CAN BE REPAIRED.
> ANYONE OUT THERE THAT CAN GIVE THE SPECIFICS OR
>EVEN THE REASONING BEHIND THIS PUBLICATION???
>
>JUST CURIOUS, AND IF IT WORKS I'M NOT
>COMPLAINING.
>
>FREDDIE
Freddie,
Sorry for the delay in my response, I have been out of the office. My
comment regarding repairing leaking pipe by using ammoniated water received
some interest. The reference is:
Chemistry of lime in ammoniated water for sealing concrete pipelines.
University of California Ag. St. Bulletin. No. 841. Doneen and Tanji. 1969.
U.C. Davis.
Regards,
Don Pitts
>-------------------------------------------------------------------
>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: Tue, 03 Sep 1996 08:25:40 -0700
From: "Blake L. Sanden" .<.blsanden@ucdavis.edu.>.
Subject: Sealing concrete pipe & precip of lime w/ high HCO3- and NH3
Freddie and the rest of the Tricklers,
I can't resist any longer. The publication talking about the technique of
sealing concrete pipe by precipitation of lime during NH3 injection is an
old Univ of California Experiment Station Bulletin 841 by L.D. Doneen and
K.K. Tanji, 1969. Some excellent discussion of Ca++ and HCO3- chemistry is
in this volume. It is out of print but I have a copy (52 pp).
How does this impact microirrigation? We all use common standards for Fe,
Mn, and HCO3 levels that can cause clogging/precip problems but we often
forget about fertilizer or gyp injection interactions that may not clog a
system but they can precipitate the PO4 or free Ca that we're trying to
inject to benefit fertility or soil structure. The material in this
bulletin could be reworked for some excellent guidelines for the gypsum
injection business that has exploded here in the southern San Joaquin Valley.
How about it Jim Oster? Can we get Ken interested in this approach?
Blake Sanden
UC Irrigation & Agronomy Farm Advisor, Kern County
blsanden@ucdavis.edu
At 03:15 PM 8/31/96 -0500, you wrote:
>A NO-NO, BUT I DID GET A CHUCKLE THAT
>>THERE IS A PUBLICATION ON REPAIRING LEAKY
>>PEAK WITH ANHYDROUS AMMONIA INJECTION.
>>
>> BUT WOULD BE AMUSED TO KNOW
>>WHAT SIZE LEAKS CAN BE REPAIRED.
>> ANYONE OUT THERE THAT CAN GIVE THE SPECIFICS OR
>>EVEN THE REASONING BEHIND THIS PUBLICATION???
>>
>>JUST CURIOUS, AND IF IT WORKS I'M NOT
>>COMPLAINING.
>>FREDDIE
>>Keep at it till you get the answer, I am also wondering-
>But perhaps they really mean those old tyre pipes called "leaky pipe"
> Jean/
>PS How does that fit in micro irrigation , is it not micro-plumbing?
>
>
>
<------------------------------>
End of Digest
************************
Contents:
Re: Sealing concrete pipe & precip of lime w/ high HCO3- and ("J.D. Oster" .<.oster@mail.ucr.edu.>.)
<---------------------------------------------------------------------->
Date: Tue, 3 Sep 1996 11:31:48 -0500
From: "J.D. Oster" .<.oster@mail.ucr.edu.>.
Subject: Re: Sealing concrete pipe & precip of lime w/ high HCO3- and
Thanks, Blake for the WW challange! But, I believe the folks at the
Irrigation Center at CalState San Luis Obsipo have a manual which likely
covers the subject. As for in-house expertize, contact Larry Swankel. These
sources of information would need to be contacted before beginning the
planning process to revise the 52 page document of Doneen and Tanji. At
11:18 AM 9/3/96 -0500, you wrote:
>Freddie and the rest of the Tricklers,
>
>I can't resist any longer. The publication talking about the technique of
>sealing concrete pipe by precipitation of lime during NH3 injection is an
>old Univ of California Experiment Station Bulletin 841 by L.D. Doneen and
>K.K. Tanji, 1969. Some excellent discussion of Ca++ and HCO3- chemistry is
>in this volume. It is out of print but I have a copy (52 pp).
>
>How does this impact microirrigation? We all use common standards for Fe,
>Mn, and HCO3 levels that can cause clogging/precip problems but we often
>forget about fertilizer or gyp injection interactions that may not clog a
>system but they can precipitate the PO4 or free Ca that we're trying to
>inject to benefit fertility or soil structure. The material in this
>bulletin could be reworked for some excellent guidelines for the gypsum
>injection business that has exploded here in the southern San Joaquin Valley.
>
>How about it Jim Oster? Can we get Ken interested in this approach?
>
>Blake Sanden
>UC Irrigation & Agronomy Farm Advisor, Kern County
>blsanden@ucdavis.edu
>
>
>At 03:15 PM 8/31/96 -0500, you wrote:
>>A NO-NO, BUT I DID GET A CHUCKLE THAT
>>>THERE IS A PUBLICATION ON REPAIRING LEAKY
>>>PEAK WITH ANHYDROUS AMMONIA INJECTION.
>>>
>>> BUT WOULD BE AMUSED TO KNOW
>>>WHAT SIZE LEAKS CAN BE REPAIRED.
>>> ANYONE OUT THERE THAT CAN GIVE THE SPECIFICS OR
>>>EVEN THE REASONING BEHIND THIS PUBLICATION???
>>>
>>>JUST CURIOUS, AND IF IT WORKS I'M NOT
>>>COMPLAINING.
>>>FREDDIE
>>>Keep at it till you get the answer, I am also wondering-
>>But perhaps they really mean those old tyre pipes called "leaky pipe"
>> Jean/
>>PS How does that fit in micro irrigation , is it not micro-plumbing?
>>
>>
>>
>
>
J.D.(Jim) Oster
Dept. of Soil & Env. Sciences
University of California
Riverside, CA 92521
Phone (909)787-5100
FAX (909)787-5522
<------------------------------>
End of Digest
************************
Contents: A comment from a new Trickle-L member (Richard Mead .<.rmead@cybergate.com.>.) Re: A comment from a new Trickle-L member (RobertK195@aol.com) <---------------------------------------------------------------------->
Date: Wed, 4 Sep 1996 19:45:16 GMT From: Richard Mead .<.rmead@cybergate.com.>. Subject: A comment from a new Trickle-L member The following was sent to me from Farhad Fassihi. R. Mead Trickle-L owner/manager ---------------------------------------------------- Hello there; Thank you very much for including me on your mailing list. I am a manufacturing engineer or to be more precise plastics processing specialist. I was recently confronted with a challenge to design and make surface irrigation PE tubing. I thought the best way of designing for this particular product is to recognize the real needs and by that to appreciate what every-body else was doing. This includes potential problems and requirements that users might express. Your forum (at least seems to me) a forum of users and I am very much an outsider. However, I am trying to learn about your experiences and if possible put that to a good use by designing better tools for people like yourselves. I am a lecturer in polymer processing technology at the Nottingham Trent University, at the heart of the Robin Hood country. I am interested in a list of manufacturers of equipment for this particular aplication and if possible product samples that I could have a look at. I am also interested to hear from people who are involved in this area of technology and are prepared to share some technical know-how. I hope this is a good enough introduction and look forward to hear from all you learned friends. yours truley Farhad Fassihi <------------------------------>
Date: Thu, 5 Sep 1996 01:30:16 -0400 From: RobertK195@aol.com Subject: Re: A comment from a new Trickle-L member Now that chap sounds ready for most anything. Must have learned from Robin Hood. Here are some *real world* problems with surface irrigation tubing. I'm not sure just how narrowly you define surface irrigation tubing, so I'll include problems I've encountered for any kind of plastic tubing laid on the ground, and used for irrigation. A. Drip hose, that is, tubing with built-in emitters. This comes in several kinds, each with it's own set of problems. If it is thin and flexible, it will kink easily, get damaged by being driven over, or even walked upon, and is chewed upon by several kinds of thirsty rodents seeking the water inside. No to mention coyotes, dogs, raccoons, skunks and 'possums. Many types of drip tubing are made with a seam lengthwise along the hose. Water will travel on the outside along this seam instead of dripping off at the emitter... a frustrating thing if one is trying to water a small plant placed next to the emitter! The manufacturer carefully instructs to lay the hose with the emitters on the top side (to prevent plugging), but when the water ends up several feet away from the plant, you put the emitters on the underside the next time! Good for business! B. If it is more rigid, and the emitters are individual hard plastic inserts, then the hose will get damaged if driven upon, where the soft hose is crushed against the hard emitter. Or the hard emitters will crush and break. If the emitters are welded inside of the hose, they will come loose if driven upon. C. A rigid hose into which emitters are inserted in punched holes is nice the first time it is made up and used, but just try to move it without the emitters pulling out. And the barb inside will punch through the back side of the hose if driven upon. The above mentioned problems lead to the need for repairs. One must cut the hose, insert some sort of a repair coupling, and then fasten the thing in place, often under water pressure, and sometimes in a muddy hole in the ground, or among stickery vines. A messy circumstance, unpleasant at best, and disagreeable on a cold day. What the world needs is, first, drip hose that does not need repairs (ha!), or, if repair we must, then please invent some sort of a hand held ray gun that will insert a repair coupling and weld it in place, without leaks, under water pressure, in muddy cramped places, without a power cord, and for a few pennies per repair! Or better, forget the coupling, just heal the hose. Maybe just a drip hose band-aid is all we need. If the post-it-notes adhesive guy could make a less-sticky glue, then let's make a more-sticky glue that will glom onto our slick drip hose material, under water, and stay put. For good. As for surface hose used merely to transport water, that is, no emitters, the current crop of hose is not too bad, except that one must terminate, couple, repair or otherwise apply devices called fittings. Alas, one develops hands like Big Foot after thrusting barbed fittings into black plastic hose all day long. Or perhaps the hose into the fittings. Again, how about a ray gun to merely grip those wretched fittings, and squeeze the hose in place as needed? I have employed drip irrigation for over 30 years now, and it sure would be nice to one of these days let the automated system turn itself on, and know for sure that the above problems aren't letting water spurt out all over the place. One must *always* survey the farm, and make those unpleasant repairs. It's possible your task relates to larger diameter plastic tubing, used to transport water, and perhaps with gates to release water into furrows. I have no experience with these types, but no doubt the same problems scale up geometrically, hopefully not exponentially. Enough ranting. Give Robin my regards. <------------------------------>
End of Digest ************************
Contents:
Re: Robert K's drip hose repairs (Merriott@aol.com)
Re: WELCOME TO TRICKLE-L !! (=?iso-8859-1?Q?Lehrstuhl_f=FCr_Gem=FCsebau?=)
Re: WELCOME TO TRICKLE-L !! -Reply ("Bruce Metelerkamp" .<.BRUCE@mailgate.icfrnet.unp.ac.za.>.)
Rodent damage (FLamm@oznet.ksu.edu (Freddie Lamm))
<---------------------------------------------------------------------->
Date: Thu, 5 Sep 1996 22:16:01 -0400
From: Merriott@aol.com
Subject: Re: Robert K's drip hose repairs
Robert mentioned how handy a ray gun might be that would allow you to easily
make drip hose repairs without having to cut into the hose and put in a new
fitting and deal with all those stickery vines. Robert, it is especially fun
in S. Florida when a friendly colony of fire ants has built near the site of
the leak. All that water sloshing around and the only dry spot the ants can
find is up your leg!
Actually something even better than a ray gun may not be too far off. Maybe
in 20 or 30 more years we'll be able to use nanotechnology (microscopic
machines) to repair drip hoses. Imagine an army (navy?) of these gizmos,
complete with onboard computers, injected at the well site, searching out
areas of higher than normal flow and sealing off the leaks. Or maybe by
then, we'll have developed a polymer that acts like artificial skin,
resealing itself at the site of any leak. It's not as farfetched as it
sounds. For a good introduction, see K. Eric Drexler's "Engines of
Creation."
Randall Merriott
Merriott@aol.com
<------------------------------>
Date: Fri, 6 Sep 1996 10:15:17 +-200
From: =?iso-8859-1?Q?Lehrstuhl_f=FCr_Gem=FCsebau?=
Subject: Re: WELCOME TO TRICKLE-L !!
------ =_NextPart_000_01BB9BDC.51605A00
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Dear Mr. Mead,
thanks for your care for all new members of your list, I=B4m one of =
them. My name is Tino C. Mosler, I am a researcher / PhD student at =
Technische University Muenchen / Germany. For my exact address please =
see attached file sender.txt.
1) Briefly, what is your affiliation with trickle/drip irrigation?
I am doing my thesis on drip irrigation / fertigation in vegetables for =
processing. My experiments are done in Niederbayern, a region with some =
thousand ha of vegetables. Objective of the work is to identify the most =
promising process for drip (e.g. where to place the drip-tape, =
scheduling of irrigation, questions of fertigation) under a strong =
emphasis of pratical suitability. During growing season irrigation is =
needed only for 60-70 days a year, so a simple and cheap process is =
necessary in order to gain acceptance by the local farmers, since drip =
is a new technique in the region. Up till recently overhead irrigation =
was standard.
2) What crops or plants do you use drip irrigation on?
Pickling cucumbers
3) If using subsurface drip irrigation, what is the average depth of
placement of the drip lateral?=20
About 5cm (2 inch)
4) What problems have you encountered with drip irrigation?
Leaks, acceptance by 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?
Kristalon blue and white (blue: 19 -6-20-3+trace-elements; white: =
15-5-30+ trace-elements)
Ca(NO3)2 all three of them with good results, more a question of price!
6) Have you experienced a reduction in fertilizer and/or water use?
Reduction of water use comparing to overhead irrigation. Regarding =
fertilizer it is depending on your strategy
7) Do you have water quality problems? If so, how do you tackle the =
situation?
no
8) How frequent do you irrigate? Many times a day or just one long =
session
per day or several days?
Once per day
9) Do you have rodent damage? If so, how do you control the problem?
Yes some. Good experience with little cups now and than under an =
emitter of a dripline on surface. Rodents use it as drinking trough and =
don=B4t damage the hoses. Considerable reduction of damage as result of =
this praxis.
10) Are you pleased with the uniformity of your system or systems? Were =
they
designed correctly?
yes
11) How did you find out about our mailing list?
Virtual library on irrigation in Kassel University, Germany
Address: http://fserv.wiz.uni-kassel.de/kww/index.html
all the best
Tino
=20
------ =_NextPart_000_01BB9BDC.51605A00
Content-Type: text/plain; name="Sender.txt"
Content-Transfer-Encoding: quoted-printable
Tino C. Mosler (MSc. Agriculture)
TU - M=81nchen, Vegetable section
85350 Freising, Germany
Tel: 49-(0)8161-713157
Fax: 49-(0)8161-713433
e-mail: veginst3@pollux.edv.agrar.tu-muenchen.de
------ =_NextPart_000_01BB9BDC.51605A00--
<------------------------------>
Date: Fri, 6 Sep 1996 11:48:01 +200
From: "Bruce Metelerkamp" .<.BRUCE@mailgate.icfrnet.unp.ac.za.>.
Subject: Re: WELCOME TO TRICKLE-L !! -Reply
Now that is what I call a novel and useful tip - working with
nature and not against her by supplying the thirsties with water
- that would have leaked away anyway, to prevent them damaging
lines. !
Well done those guys - has anyone else thought of, or done this?
>>
Tino C. Mosler (veginst3@pollux.edv.agrar.tu-muenchen.de)
wrote:
9) Do you have rodent damage? If so, how do you control the
problem?
Yes some. Good experience with little cups now and than under
an emitter of a dripline on surface. Rodents use it as drinking
trough and don't damage the hoses. Considerable reduction of
damage as result of this practice.
<<
Regards
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.
Bruce Metelerkamp SOIL WATER RESEARCH OFFICER
Institute for Commercial Forestry Research,
University of Natal, PO Box 100281
Scottsville, ZA3209
Rep. of South Africa Voice:27 331 62314
E-mail: bruce@icfr.unp.ac.za FAX:27 331 68905
URL http://www.icfrnet.unp.ac.za/~metele
/SoWaCS.html
/RR.html
Host of SoWaCS (Soil Water Content Sensor) Discussion List.
SEND info sowacs OR subscribe sowacs TO
majordomo@aqua.ccwr.ac.za
<------------------------------>
Date: 06 Sep 96 09:03:46 CDT
From: FLamm@oznet.ksu.edu (Freddie Lamm)
Subject: Rodent damage
It is my understanding that most rodents need to chew or knaw on hard
objects to keep there teeth wore down. So, thirst is not the only
reason they would chew on a dripline. I doubt they chew on
electrical wires for electricity. BUT if little cups help that's
fine for surface drip but not much help for SDI. I have heard that
rabbits chew through surface driplines in rows JUST so they can have
a straight and clear exit in an emergency (ie. fox, coyote or dog).
The person that related this to a tour group was the head of a drip irrigation
manufacturing company. The head related that in their situation of short rows,
they solved the problem by partial blocking of the row entrances.
This removed another straight line path and the rabbits decided other places were
more appropriate to live and play.
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. ------
<------------------------------>
End of Digest
************************
Contents: (Juan Ramsn Castel .<.jrcastel@master.ivia.es.>.) <---------------------------------------------------------------------->
Date: Sat, 7 Sep 1996 13:28:14 +0100 From: Juan Ramsn Castel .<.jrcastel@master.ivia.es.>. Subject: <------------------------------>
End of Digest ************************
Contents: Re: TRICKLE-L digest 577 (TPiatkowsk@aol.com) <---------------------------------------------------------------------->
Date: Sun, 8 Sep 1996 00:49:11 -0400 From: TPiatkowsk@aol.com Subject: Re: TRICKLE-L digest 577 Don Pitts, We have been nusing both these compounds effectively in California for several purposes. If you would like me to send you further information, please e-mail me your address. Tom Ag H20 <------------------------------>
End of Digest ************************
Contents: Re: TRICKLE-L digest 577 (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.) I didn't know I had been dropped. (LodiCraig@aol.com) YOU WEREN'T DROPPED...SORRY ANYWAY (Richard Mead .<.rmead@cybergate.com.>.) <---------------------------------------------------------------------->
Date: Sun, 08 Sep 1996 17:49:39 -0500 (EST) From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>. Subject: Re: TRICKLE-L digest 577 Tom Ag H20, I assume you are responding to the following question: "I am interested in products that might be effective at dissolving or removing various forms of iron scale in micro irrigation systems. Does anyone have experience with the use of hydroxyacetic acid or suflamic acid?" Please send me what experiences or information that you have on the use of these acids for scale removal. Thanks Don Pitts e-mail: djp@icon.imok.ufl.edu At 11:51 PM 9/7/96 -0500, you wrote: >Don Pitts, > >We have been nusing both these compounds effectively in California for >several purposes. If you would like me to send you further information, >please e-mail me your address. > >Tom >Ag H20 > <------------------------------>
Date: Mon, 9 Sep 1996 00:33:51 -0400 From: LodiCraig@aol.com Subject: I didn't know I had been dropped. Hi Richard! How did I get dropped from the list? Was I bad? How are you dude? Did you have a memorable experience at the Olympics? Harvest is on and intense! Should be a little more rational after this next week ... things seem to be spreading out now. Cheers, Craig <------------------------------>
Date: Mon, 9 Sep 1996 15:11:54 GMT From: Richard Mead .<.rmead@cybergate.com.>. Subject: YOU WEREN'T DROPPED...SORRY ANYWAY Craig, I noticed that you had resubscribed but I had no idea that this was unintentional. I figured you were so busy with harvest that you dropped Trickle-L until the fall. Believe it or not, I was dropped somehow too. This was about 5 months ago. Don't ask me how it happens I hope we're the only ones. The guys at University of Nebraska at Lincoln can't figure it out either. Once again, my apologies. Hope this doesn't happen ever again. I don't want to loose one of my star participants :-) R. Mead At 11:32 PM 9/8/96 -0500, you wrote: >Hi Richard! > >How did I get dropped from the list? Was I bad? > >How are you dude? Did you have a memorable experience at the Olympics? > >Harvest is on and intense! Should be a little more rational after this next >week ... things seem to be spreading out now. > >Cheers, >Craig > <------------------------------>
End of Digest ************************
Contents:
RE: YOU WEREN'T DROPPED...SORRY ANYWAY ("Donald W. Ricketts" .<.donr@scvnet.com.>.)
Olives & Pomegranates ("Donald W. Ricketts" .<.donr@scvnet.com.>.)
Greetings (Christopher A Chapman .<.cchapman@GAS.UUG.Arizona.EDU.>.)
(dmacken@cybergate.com (David Mackenzie))
<---------------------------------------------------------------------->
Date: Mon, 9 Sep 96 11:01:13 PDT
From: "Donald W. Ricketts" .<.donr@scvnet.com.>.
Subject: RE: YOU WEREN'T DROPPED...SORRY ANYWAY
Have been trying to unsubscribe, but I can't fathom the directions.
I type "unsubscribe trickle_l" and variations, but I'm still on.
I subscribed because I wanted to ask for help on using trickle for
olive and pomegranate orchards, but I could never find directions
on how to send a message. I'm sure this is all very simple, but
these things baffle me. Sorry to trouble you. Don Ricketts
<------------------------------>
Date: Mon, 9 Sep 96 13:23:09 PDT
From: "Donald W. Ricketts" .<.donr@scvnet.com.>.
Subject: Olives & Pomegranates
Am planting above on hillside--foothills at beginning high desert
in Southern California. summer temperatures almost always in 90s
during day---often over 100--with 50s at night. In winter, daytime
temps are in 70s-80s, 40s at night with an occasional light frost.
Sandy, rocky soil. Would appreciate any information anyone may
have about how to use drip for these crops under these conditions.
How big a dripper, how long on. Please e-mail to me as I don't
understand lists---donr@scvnet.com. Thanks-------Don Ricketts
<------------------------------>
Date: Mon, 9 Sep 1996 18:49:24 -0700 (MST)
From: Christopher A Chapman .<.cchapman@GAS.UUG.Arizona.EDU.>.
Subject: Greetings
To everyone at Trickle-L:
I am a senior undergrad at the University of Arizona, Agricultural and
Biosystems Engineering Dept., and I have just subscribed to the list.
I don't have alot of experience with drip systems yet, but I'm doing a
a senior design project for a field at the Maricopa Agricultural Center,
with the following specifications:
Crop: cotton
Area: 92 acres
Soil: clay-loam
Line Source Emitter: Turbo T-Tape (maybe?)
I would greatly appreciate any advice w/ respect to the design of such a
system, including:
-sources of Kc values for a Penman-method grass ETref.
-information about the manufacturer of Turbo-T tape, or advice on
inexpensive suppliers
-I'll be irrigating with CAP water, and using a media filter, any
suggestions about this?
I would especially appreciate any response from Ron Ennor, since I know
that cotton-crop conditions are comprable in Israel to Arizona (highs
above 115 F for over 3 months). Also, what sort of Management Allowable
Depletion should be used, or how is it chosen?
Many Thanks,
Christopher Chapman
<------------------------------>
Date: Tue, 10 Sep 1996 15:27:46 GMT
From: dmacken@cybergate.com (David Mackenzie)
Subject:
unsubscribe David Mackenzie
<------------------------------>
End of Digest
************************
Contents: Re: Greetings (GroAire@aol.com) Re: Greetings (EVALOV@aol.com) Re: Greetings (Christopher A Chapman .<.cchapman@GAS.UUG.Arizona.EDU.>.) <---------------------------------------------------------------------->
Date: Tue, 10 Sep 1996 22:01:41 -0400 From: GroAire@aol.com Subject: Re: Greetings Contact Howard Wuertz of Sundance Farms in Coolidge, Az. He has about 5,000 acres of drip under melons, peppers and cotton. He should prove to be a valuable resource. If you need phone numbers, recontact me and I will provide them. Before you purchase your tape and filters, I would like the opportunity to bid the job. I have been selling installations throughout the U.S. and would appreciate the chance to service your needs. Dave Enyeart Sr. Engineer GroAire Irrigation Inc. GroAire@aol.com <------------------------------>
Date: Wed, 11 Sep 1996 01:12:55 -0400 From: EVALOV@aol.com Subject: Re: Greetings I would say "proceed with caution". Dave is right, Sundance Farms could provide some of the ground work to subsurface drip, it's quite impressive! But, keep in mind, many of the factors leading to a successful subsurface irrigation system are sensitive to regional influences and cultural pratices. At any rate, there seems to be a learning curve to managing and operating a subsurface system successfully. My advice, would be to find a local dealer that can work with you on the operation of your system. Here in California, we have a "Dealers Association", which could provide a list of dealers that do work of that kind. The Association could also provide you with a copy of the "Consumers Bill of Rights", (key design critira and operation of a low volume irrigation system). I hope this is of some help. <------------------------------>
Date: Wed, 11 Sep 1996 09:29:17 -0700 (MST) From: Christopher A Chapman .<.cchapman@GAS.UUG.Arizona.EDU.>. Subject: Re: Greetings Thanks for the advice everyone, and I would appreciate any phone numbers, E-mail addresses, etc. for Howard Wuertz or a "dealers association" in Arizona or the one in California (the "Consumer's Bill of Rights" sounds interesting). To Dave: I'm not sure if the end design will actually be installed, but I will definitely contact you first. <------------------------------>
End of Digest ************************
Contents: Re: Greetings (ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>.) <---------------------------------------------------------------------->
Date: Wed, 11 Sep 1996 16:51:53 -0700 (PDT) From: ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>. Subject: Re: Greetings Dear Christopher: I have a agronomic testing consulting lab in blythe CA. I do work with another consultant who specializes in drip irrigation in INdio CA. His name is Gideon Cohn. He can be reached at GIDCO 619-398-2996. best regards, Aron Quist, CPAg/SS At 09:00 PM 9/9/96 -0500, you wrote: >To everyone at Trickle-L: > >I am a senior undergrad at the University of Arizona, Agricultural and >Biosystems Engineering Dept., and I have just subscribed to the list. > >I don't have alot of experience with drip systems yet, but I'm doing a >a senior design project for a field at the Maricopa Agricultural Center, >with the following specifications: > >Crop: cotton >Area: 92 acres >Soil: clay-loam >Line Source Emitter: Turbo T-Tape (maybe?) > >I would greatly appreciate any advice w/ respect to the design of such a >system, including: > -sources of Kc values for a Penman-method grass ETref. > -information about the manufacturer of Turbo-T tape, or advice on > inexpensive suppliers > -I'll be irrigating with CAP water, and using a media filter, any > suggestions about this? > >I would especially appreciate any response from Ron Ennor, since I know >that cotton-crop conditions are comprable in Israel to Arizona (highs >above 115 F for over 3 months). Also, what sort of Management Allowable >Depletion should be used, or how is it chosen? > >Many Thanks, >Christopher Chapman > > <------------------------------>
End of Digest ************************
Contents: Testing Soil For pH--Use of Suction Lysimetry (Irrometer@aol.com) <---------------------------------------------------------------------->
Date: Fri, 13 Sep 1996 15:15:48 -0400 From: Irrometer@aol.com Subject: Testing Soil For pH--Use of Suction Lysimetry Our company has manufactured suction lysimeter tubes for over 25 years. These devices are constructed of a porous ceramic cup solvent welded to 1/2" Schedule 40 PVC tubing. In the early days they were pretty well exclusively used for doing salinity work (EC). With the advent of fertigation systems (particularly with microirrigation), they have been used to check the soil solution for nitrate nitrogen and P & K (to a lesser extent). In the past several months there have been reports made to us that their use to check soil pH was giving very mixed results. This message is intended to advise users of this suction extract technique, that suction extract analysis for soil pH is not recommended even when the ceramic cup has been acid treated and thoroughly rinsed in a dilute salt solution to remove the acid in the ceramic pores and adsorbed hydrogen from the ceramic (as most researchers do in preparing these tubes for use). The principal problem is that the partial pressure of carbon dioxide inside the soil and in the ceramic cup are not equal. Outgassing of dissolved carbon dioxide in the soil solution will occur as the soil solution collects in the ceramic cup. This outgassing will cause the pH of the extracted solution to be higher than in the soil solution by an amount which depends on the difference between the partial pressure of the carbon dioxide in the soil and that inside the extractor. A secondary problem results from minerals in the ceramic generated during the firing process to make the ceramic. Some of the minerals are soluable and can increase the pH of the soil solution which comes into contact with the cup. The acid washing and thorough rinsing of the cups, done by many reasearchers as a pretreatment before using the extractors, removes these minerals. This mitigates the secondary problem, but does not eliminate the problem of carbon dioxide outgassing. THUS--the fact remains, that the use of suction extract analysis for measuring soil pH is not an accepted or recommended analytical procedure. This is our advice as well as the advice of all of the scientists and lab technicians that I have talked with on this subject in the recent past. One final point worth noting is the fact that once you have finished using them in the field, they should be thoroughly cleaned before they are put into storage (before the ceramic cups are allowed to air dry). At the least, they should be scrubbed with clean water, filled with distilled water and allowed to drain so as to flush the cups. Procedures on acid washing and rinsing are available--as it is practiced by the scientists here at the University of California. Regards, Bill Pogue, President, Irrometer Company, Inc. <------------------------------>
End of Digest ************************
Contents: Re: Testing Soil For pH--Use of Suction Lysimetry (ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>.) <---------------------------------------------------------------------->
Date: Sat, 14 Sep 1996 12:02:58 -0700 (PDT) From: ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>. Subject: Re: Testing Soil For pH--Use of Suction Lysimetry Dear Bill: You have a good point. There are other reasons why a comparison of a suction lysimeter extract pH should not be compared with a Lab check. Labs normally use de-ionzed water as the reagent solute. Using an irrigation source may contribute buffers to the soil not normally included and which may or may not affect pH. Also, pH should be measured in a saturation paste, at least in my opinion. In suction lysimeter extracts there is no control over the concentration of the extract. Depending upon conditions, the lysimeter may extract solution from a super-saturated soil or from a soil at field capacity or lower matrix potential. I have noticed that labs that use a 1:1 ratio of soil to water have a consistantly higher pH then those that use the SP upon the duplicate samples. Aron Quist, CPSS At 02:23 PM 9/13/96 -0500, you wrote: > Our company has manufactured suction lysimeter tubes for over >25 years. These devices are constructed of a porous ceramic >cup solvent welded to 1/2" Schedule 40 PVC tubing. In the early >days they were pretty well exclusively used for doing salinity >work (EC). With the advent of fertigation systems (particularly >with microirrigation), they have been used to check the soil >solution for nitrate nitrogen and P & K (to a lesser extent). >In the past several months there have been reports made to us that >their use to check soil pH was giving very mixed results. This >message is intended to advise users of this suction extract >technique, that suction extract analysis for soil pH is not >recommended even when the ceramic cup has been acid treated >and thoroughly rinsed in a dilute salt solution to remove the acid >in the ceramic pores and adsorbed hydrogen from the ceramic >(as most researchers do in preparing these tubes for use). > The principal problem is that the partial pressure of carbon dioxide >inside the soil and in the ceramic cup are not equal. Outgassing of >dissolved carbon dioxide in the soil solution will occur as the soil >solution collects in the ceramic cup. This outgassing will cause >the pH of the extracted solution to be higher than in the soil >solution by an amount which depends on the difference >between the partial pressure of the carbon dioxide in the soil >and that inside the extractor. > A secondary problem results from minerals in the ceramic >generated during the firing process to make the ceramic. >Some of the minerals are soluable and can increase the >pH of the soil solution which comes into contact with the >cup. The acid washing and thorough rinsing of the cups, >done by many reasearchers as a pretreatment before using >the extractors, removes these minerals. This mitigates the >secondary problem, but does not eliminate the problem >of carbon dioxide outgassing. > THUS--the fact remains, that the use of suction extract >analysis for measuring soil pH is not an accepted or >recommended analytical procedure. This is our advice >as well as the advice of all of the scientists and lab >technicians that I have talked with on this subject in the >recent past. > One final point worth noting is the fact that once you have >finished using them in the field, they should be thoroughly >cleaned before they are put into storage (before the ceramic >cups are allowed to air dry). At the least, they should be scrubbed >with clean water, filled with distilled water and allowed to >drain so as to flush the cups. Procedures on acid washing >and rinsing are available--as it is practiced by the scientists >here at the University of California. >Regards, Bill Pogue, President, Irrometer Company, Inc. > > <------------------------------>
End of Digest ************************
Contents: Buried dripper line in blackberries. (polson@orednet.org (Phil Olson)) Re: Buried dripper line in blackberries. (Jerome Pier .<.jpier@interramp.com.>.) <---------------------------------------------------------------------->
Date: Sat, 14 Sep 1996 17:07:13 -0700 From: polson@orednet.org (Phil Olson) Subject: Buried dripper line in blackberries. I am commercial blueberry, boysenberry and marion blackberry grower. I use a drip system in my blueberry fields only. Currently I am in the process of planning for additional plantings of blackberries. While I have always used an overhead irrigation system for these berries, I am considering using a buried 2 line (one on each side of the row) micro system. The prevailing soil type is a clay loam. I can come up with many good cultural reasons why this could be a very good system however I'm concerned that with a permanent (15 year) crop I might have nothing but a root plugged mess after a short time. I've heard by some, on these forum, that root plugging can be dealt with but the blackberry grows quite vigorously and might be quite different than crops other have had experience with. Any thoughts or comments would be very much apprecitated. Thank you - Phil Olson -- <------------------------------>
Date: Sun, 15 Sep 1996 02:03:43 -0700 From: Jerome Pier .<.jpier@interramp.com.>. Subject: Re: Buried dripper line in blackberries. Phil Olson wrote: [stuff deleted] > however I'm concerned that with > a permanent (15 year) crop I might have nothing but a root plugged mess > after a short time. > > Any thoughts or comments would be very much apprecitated. > > Thank you - Phil Olson > > -- > Phil, Trifluralin-5 by Gowan Chemical in Yuma AZ is labeled for chemigation through buried drip systems to preven root intrusion. Several people have expressed concern about the use of trifluralin as far as possible crop injury. The amounts recommended on the label are very small and should not cause any damage if used according to the label. The desired effect is to create a small (2-4" diameter) zone of chemical about the emitter. The chemical is applied just at the end of an irrigation cycle. Make sure the maximum root development has occured before chemigating. The greatest risk for root intrusion occurs when you cease to irrigate. When irrigation stops, then roots follow the shrinking soil moisture gradient back to the emitter outlet. One can also use acid to "burn" back the roots from the emitters. Lower the water pH to 4-5 and apply the acid toward the end of the irrigation cycle. The trifluralin treatment should be more effective, however. Contact: Anne Stout Product Manager Gowan Chemical 1644 Engler Ave. P.O. Box 5569 Yuma AZ 85366-5569 Phone: (520) 783-8844 FAX: (520) 343-9255 Sincerely, Jerome Pier Agronomist/Soil Scientist Netafim Irrigation, Inc. jpier@interramp.com <------------------------------>
End of Digest ************************
Contents: Re: Buried dripper line in blackberries. (Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell)) Hello (Yan.Diczbalis@DPIF.nt.gov.au) Seminars on Irrigation Scheduling (Trevor Finch .<.rsne@mpx.com.au.>.) <---------------------------------------------------------------------->
Date: Sun, 15 Sep 96 11:07:36 -0500 From: Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell) Subject: Re: Buried dripper line in blackberries. Dear Phil and Trickle-l Many years of research have been conducted on the use of drip (on the surface and buried, two lines and one) on blueberries in central Minnesota. Jerry Wright is the head scientist. The soil is a sandy loam, very much different from your own. I cannot recall the results of the study but the berries sure did taste good. I believe Jerry is a subscriber to trickle-L. C'mon Jerry--give us the low down! Jed. > > >I am commercial blueberry, boysenberry and marion blackberry grower. I use >a drip system in my blueberry fields only. Currently I am in the process >of planning for additional plantings of blackberries. While I have always >used an overhead irrigation system for these berries, I am considering >using a buried 2 line (one on each side of the row) micro system. The >prevailing soil type is a clay loam. I can come up with many good cultural >reasons why this could be a very good system however I'm concerned that with >a permanent (15 year) crop I might have nothing but a root plugged mess >after a short time. I've heard by some, on these forum, that root plugging >can be dealt with but the blackberry grows quite vigorously and might be >quite different than crops other have had experience with. > >Any thoughts or comments would be very much apprecitated. > >Thank you - Phil Olson > >-- > > > **************************************************** * Jed T. Waddell * * Graduate Research Assistant * * University of Minnesota * * Department of Soil, Water, and Climate * * St. Paul, MN 55108 * * office (612) 625-1968 * * fax (612) 625-2208 * **************************************************** <------------------------------>
Date: Mon, 16 Sep 1996 11:13:16 +0930 From: Yan.Diczbalis@DPIF.nt.gov.au Subject: Hello Dear Trickle-L members Here are the answers to Richard Meads 11 introductory questions. Thanks for the welcome. 1. I am a Senior Horticulturist with the Northern Territory Department of Primary Industry and Fisheries. My mission statement is tree water use and irrigation management. Here in Darwin we are working on water requirements and irrigation management of a range of tropical fruit crops (Mango, Rambutan, Banana, Durian, Mangosteen etc). Our irrigation monitoring devices include, tensiometers (digital), neutron moisture probe and capacitance probe (EnviroScan). 2. Irrigation systems are mainly under tree micro sprinklers, however, drip tape is a popular system for our vegetable growers (melons, tomatoes, etc.). Some of our pioneering Cashew growers are considering drip irrigation despite problems which have occurred with root blockage in the past. Mango growers are also interested in trying drip irrigation due to the perceived lower costs of installation. We have not as yet conducted any research on drip irrigated tropical tree crops 3. Subsurface irrigation is used by our landscaping industry, particularly in grass amenity areas. Placement depth approximately 10-20 cm. 4. Problems with drip are minimal in well maintained systems. Maintaining clean emitters when fertigating and when using high calcium water are some of our problems. 5. Popular forms of N,P, and K used in fertigating are; N - Urea, KNO3, MAP P - MAP K - KNO3, KCL, KSO4 6. I am unable to confirm whether growers have experienced a reduction in fertiliser and water use. Anecdotal evidence suggests that water use is reduced in drip irrigated systems. 7. In the Top-End of the Northern Territory our water quality is excellent. In southern growing areas (Katherine, Alice Springs) high levels of bicarbonates in the water start to cause problems. 8. Generally speaking our melon growers (drip tape under plastic mulch) would irrigate once per day. We have conducted studies on replacement rates and frequency of irrigation in melons (60-100% evaporation; 1-12 times/day) and found that on our soils (sandy loam's -sandy clay loam's) there was no advantage to irrigating more frequently than once per day at any of the replacement rates. 9. We don't have rodent problems, but we do have insect problems (crickets). However, the thicker walled tapes appear to overcome the problem. 10. Uniformity of well designed systems appear to be good. 11. I found out about this mail list after doing a search (Alta Vista) on irrigation. I am particularly interested in hearing from subscribers who work with tropical fruit. Is there a similar list for micro-irrigation researchers/growers? Yan Diczbalis Senior Horticulturist Northern Territory Department of Primary Industry PO Box 990 Darwin, NT, 0801. AUSTRALIA Ph +61 - 8 - 89992309 Fax +61 - 8 - 89992049 E-Mail Yan.Diczbalis@nt.gov.au <------------------------------>
Date: Mon, 16 Sep 96 16:09:01 +1000 (EST) From: Trevor Finch .<.rsne@mpx.com.au.>. Subject: Seminars on Irrigation Scheduling Seminars on Irrigation Scheduling and Crop Management, Australia, October 1996 <------------------------------------------------------------------------------>
'A practical approach using soil moisture measurements' Simon Turner, a principal with Agri-Tech Services, UK and Cape Irrigation Consultants, South Africa, will be presenting seminars in Australia on scheduling irrigations for improved crop management. Agri-Tech consults principally with fruit and vegetable growers in the UK and Europe. CIC covers a large part of southern Africa monitoring a range of crops from citrus and table grapes in the Western Cape to avocado, bananas and sugar in Swaziland. The seminars will be using case studies to illustrate how irrigations can be scheduled with precise accuracy, applying water as and when required. Such techniques allow for manipulation of crop yield and quality, of particular interest to the wine grape industry. Field monitoring becomes even more essential with modern irrigation methods such as trickle tape. The seminars will be of interest not only to growers but also to anyone considering establishing an irrigation monitoring consultancy. Irrigation Scheduling - how much to apply, and when Field Capacity - Determining the Full Point Refill Point - when to irrigate Available water in the soil profile Extent of wetting zones Irrigation efficiency Putting RDI into practice Notes will be provided. The case notes are not from research programmes, but the result of measurements made by commercial growers as part of routine crop monitoring Dates Friday 4th October 1996, Tocal College, Maitland, NSW Contact Norm Cross, NSW Dept of Agriculture +61 (49) 30 2403 fax +61 (49) 30 2410 Monday 7th October 1996, Coonawarra, SA Contact Gareth Rogers +61 (87) 249 758 m +61 (18) 838 026 Wednesday 9 October 1996, Waikerie, SA Contact Xavier Ruis, RoyMac Irrigation +61 (85) 413 346 fax +61 (85) 413 322 email .<.xavi@riverland.com.au.>. Simon Turner, Agri_Tech UK +44 (1767) 62 7334 m: +44 (374) 965 480 CIC, South Africa +27 (24) 852 6106 ---- Trevor Finch Research Services New England 8/16 Nicholson St, Balmain NSW 2041 Australia email: rsne@mpx.com.au tel: +61 (2) 9810 3563 fax: +61 (2) 9810 3323 ---- <------------------------------>
End of Digest ************************
Contents: Water use effeciency (Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell)) <---------------------------------------------------------------------->
Date: Wed, 18 Sep 96 17:24:16 -0500 From: Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell) Subject: Water use effeciency Dear trickle-l, In summarizing my work on a comparison of sprinkler and drip irrigation I often use the the term 'water use effeciency'. In several articles, water use effeciency is described by the ratio of water applied to crop yield. Does anyone know any other ways to represent 'Water Use Efficiency'? Thanks, Jed **************************************************** * Jed T. Waddell * * Graduate Research Assistant * * University of Minnesota * * Department of Soil, Water, and Climate * * St. Paul, MN 55108 * * office (612) 625-1968 * * fax (612) 625-2208 * **************************************************** <------------------------------>
End of Digest ************************
Contents:
Re: Buried dripper line in blackberries. (geoflow1@slip.net (Rodney Ruskin))
("Donald W. Ricketts" .<.donr@scvnet.com.>.)
<---------------------------------------------------------------------->
Date: Mon, 16 Sep 1996 17:58:54 -0700
From: geoflow1@slip.net (Rodney Ruskin)
Subject: Re: Buried dripper line in blackberries.
At 7:17 PM 9/14/96 -0500, Phil Olson wrote:
>I am commercial blueberry, boysenberry and marion blackberry grower. I use
>a drip system in my blueberry fields only. Currently I am in the process
>of planning for additional plantings of blackberries. While I have always
>used an overhead irrigation system for these berries, I am considering
>using a buried 2 line (one on each side of the row) micro system. The
>prevailing soil type is a clay loam. I can come up with many good cultural
>reasons why this could be a very good system however I'm concerned that with
>a permanent (15 year) crop I might have nothing but a root plugged mess
>after a short time. I've heard by some, on these forum, that root plugging
>can be dealt with but the blackberry grows quite vigorously and might be
>quite different than crops other have had experience with.
>
>Any thoughts or comments would be very much apprecitated.
>
>Thank you - Phil Olson
>
>-
The only proven long term (15 years+) products which will perform without
any risk of root intrusion are ROOTGUARD products. ROOTGUARD is the
technology whereby Treflan is fused into the plastic of the emitter to
protect the system from root intrusion. This process was invented by
Battelle PNW Laboratories to keep roots out of nuclear waste burial sites
for more than 100 years. This technology has been tested with tumble weed,
willows, fescue grass and asparagus, which are extremely aggressive.
Silverstar Farms (Les Cotton, Tel: 206 573 4770) has a system in
raspberries. ROOTGUARD products for agriculture are sold by Geoflow (800
828 3388) and Drip In (800 472-3747). Landscape and turf products are sold
by Toro.
Rodney Ruskin
geoflow1@slip.net
<------------------------------>
Date: Tue, 17 Sep 96 11:46:47 PDT
From: "Donald W. Ricketts" .<.donr@scvnet.com.>.
Subject:
un-subscribe
<------------------------------>
End of Digest
************************
Contents:
Re: Water use effeciency (Tim1Utah@aol.com)
Re: Water use effeciency (Tim1Utah@aol.com)
(Juan Ramon Castel .<.jrcastel@master.ivia.es.>.)
Water Use Efficiency ("Terry A. Howell" .<.tahowell@ag.gov.>.)
Re: Water use efficiency (reply from F. Lamm) (FLamm@oznet.ksu.edu (Freddie Lamm))
Re: Water use efficiency (reply from F. Lamm) (dreynold@cd-eso.water.ca.gov)
Re: Water use efficiency (reply from F. Lamm) (Jean Piaget .<.henri@ilink.nis.za.>.)
Water use and economic efficiency (Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell))
<---------------------------------------------------------------------->
Date: Wed, 18 Sep 1996 18:55:04 -0400
From: Tim1Utah@aol.com
Subject: Re: Water use effeciency
Sprinkler system hardware efficiency is rated in many ways. Two of the most
popular are Lower Quarter Distribution Uniformity and Scheduling Coeficient.
A common definition of efficiency is the ratio of the amount of water
applied, to that amount actualy used by the plant. Tim Wilson,
tim1utah@aol.com
<------------------------------>
Date: Wed, 18 Sep 1996 18:58:55 -0400
From: Tim1Utah@aol.com
Subject: Re: Water use effeciency
As a side note Emmision Uniformity is the technique typically used to
evaluate drip systems. The average of the lowest quarter emitters divided by
the average of all the emitters.
<------------------------------>
Date: Thu, 19 Sep 1996 09:27:20 +0200
From: Juan Ramon Castel .<.jrcastel@master.ivia.es.>.
Subject:
Unsubscribe trickle-l Juan R. Castel
Juan Ramon Castel
Recursos Naturales,
Instituto Valenciano de Investigaciones Agrarias,
Apartado Oficial, 46113 Moncada,Valencia, Spain
Tel.:34+6+1391000
Fax :34+6+1390240
<------------------------------>
Date: Thu, 19 Sep 1996 09:22:28 -0500
From: "Terry A. Howell" .<.tahowell@ag.gov.>.
Subject: Water Use Efficiency
19 Sept. 1996
Jed and Trickle-L:
There are many ways to compute "water use efficiency" (WUE). Essentially,
you had the ratio backwards (water use/yield). This ratio is called the
"transpiration ratio" when water use is based on transpiration.
Below are my definitions of WUE:
WUEt = DM/T
WUEd = DM/ET
WUEy = Y/T
WUE = Y/ET
IWUE = (Yi - Yo)/(Ii - Io))
DM -- dry matter yield (M/L^2)
T -- transpiration (L^3/L^2 or just L)
ET -- evapotranspiration (L^3/L^2 or just L)
Y -- economic yield (grain, lint, etc.) (M/L^2)
Yi -- yield with irrigation amount Ii (M/L^2)
Yo -- yield without irrigation (or with amount Io;
usually Io = 0) (M/L^2)
Ii -- irrigation amount (L^3/L^2 or just L)
Io -- irrigation amount (L^3/L^2 or just L and usually Io = 0)
WUEt -- water use efficiency - DM-transpiration (M/L^3)
WUEd -- water use efficiency - dry matter (M/L^3)
WUEy -- water use efficiency - yield-transpiration (M/L^3)
WUE -- water use efficiency (M/L^3)
IWUE -- irrigation water use efficiency (M/L^3)
M -- mass (preferably g or kg; or lbs)
L -- length (preferably m or mm; or in.)
NOTE: When SI (metric) units are used, WUE has units of
kg/m^3 [and when DM or Y are in g/m^2 and ET or T or
I are in mm then WUE (in kg/m^3) is the exact ratio
of g/m^2 per mm; it's great to see the SI units work
the way they should!]; and when English units are used,
WUE typically has units of lbs/ac per in.
You may see WUE defined as Y/I, but this not correct in my opinion (although
I have used it some and so have others). The reason that Y/I is not an
acceptable ratio characterizing irrigation is that I is only one of the
water sources influencing yield. I'm trying to get folks around here (Texas
High Plains) to stop using Y/I and use Y/(I + R) where R is growing season
rain (again defining R is a little troublesome because many want to include
rainfall for several months before planting). Even Y/(I + R) has many
problems, but it can be useful in a localized area when R represents typical
rain and Y and I are associated with high management and efficient irrigation.
Since ET = I + R + SW - Q - D (ET = evapotranspiration, I = irrigation, R =
rainfall, SW = soil water depletion, Q = runoff (both rainfall and
irrigation unless I is 'net' irrigation), and D = drainage), for many
situations approximating ET as I + R may be reasonable and far better than
using just I alone.
WUEt has rather good scientific underpinning (or really its inverse the
transpiration ratio). For many cereal crops Y = HI*DM where HI is the
harvest index (a rather conservative fraction, usually between 0.4 and 0.5),
so WUEy, WUEd, or just WUE are reasonable "stretches" from the more
fundamental "transpiration ratio" that is usually dependent mainly on
species (C3, C4, or CAM photosynthetic pathways) and environmental
evaporative demand (characterized by mean potential ET or mean vapor
pressure deficit).
I hope this is useful and clarifies the definitions of WUE.
Terry Howell
At 05:30 PM 9/18/96 -0500, you wrote:
>Contents:
>Water use effeciency (Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell))
>
>----------------------------------------------------------------------
>
>Date: Wed, 18 Sep 96 17:24:16 -0500
>From: Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell)
>Subject: Water use effeciency
>
>Dear trickle-l,
>
>In summarizing my work on a comparison of sprinkler and drip irrigation I
>often use the the term 'water use effeciency'. In several articles, water
>use effeciency is described by the ratio of water applied to crop yield.
>Does anyone know any other ways to represent 'Water Use Efficiency'?
>
>Thanks,
>Jed
>****************************************************
>* Jed T. Waddell *
>* Graduate Research Assistant *
>* University of Minnesota *
>* Department of Soil, Water, and Climate *
>* St. Paul, MN 55108 *
>* office (612) 625-1968 *
>* fax (612) 625-2208 *
>****************************************************
>
*********************************************************************
* Terry A. Howell, Ph.D., P.E. (806) 356-5746 *
* USDA-ARS (806) 356-5750 (Fax) *
* P.O. Drawer 10 tahowell@ag.gov (E-mail) *
* Bushland, TX 79012 http://www.net.usda.gov/cprl/ (Internet) *
* *
* 1/2 mi. West I-40 South Access Rd. (shipping) *
*********************************************************************
<------------------------------>
Date: 19 Sep 96 10:06:03 CDT
From: FLamm@oznet.ksu.edu (Freddie Lamm)
Subject: Re: Water use efficiency (reply from F. Lamm)
Jed wrote:
In summarizing my work on a comparison of sprinkler and drip irrigation I
often use the the term 'water use effeciency'. In several articles, water
use effeciency is described by the ratio of water applied to crop yield.
Does anyone know any other ways to represent 'Water Use Efficiency'?
Jed:
The term water use efficiency is a term relating crop performance to
water use as you indicated. There are several other efficiency terms
more related to irrigation system performance.
A good primer and listing of several of the terms is in Chapter 6,
Irrigation Efficiency and Uniformity by D.F. Heerman, W.W. Wallender
and M.G. Bos, Pages 125-149 in Management of Farm Irrigation
Systems, edited by G.J. Hoffman, T.A. Howell, and K.H. Solomon.
This is an ASAE monograph available from ASAE, 2950 Niles Road, St.
Joseph, MI 49085-9659. You can also probably email to hq@asae.org
I don't know the cost but I would guess between $45-75. The book
is probably available in most libraries for universities that have
irrigation curriculum. If not probably some of the Ag Engineers at
the university would have a copy.
Application efficiency (AE or Ea), also often referred to as
irrigation efficiency (technically, they are different), is roughly defined
as the volume of water used by ET divided by the volume delivered to
the field. As you can probably see this term handles the effects
of runoff and deep percolation.
Philosophically, **I*** say that ***BOTH*** WUE and Ea must be
optimized together or else something is getting shorted.
Uniformity is another issue you may want to read about, **BUT**
uniformity and efficiency are not the same issue, and can even
sometimes conflict.
I will send you by snail mail, a discussion on Ea and WUE, I prepared for a regional
meeting.
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: Thu, 19 Sep 96 08:11: 8 PDT
From: dreynold@cd-eso.water.ca.gov
Subject: Re: Water use efficiency (reply from F. Lamm)
Freddie Lamm wrote:
>Application efficiency (AE or Ea), also often referred to as
>irrigation efficiency (technically, they are different), is roughly defined
>as the volume of water used by ET divided by the volume delivered to
>the field. As you can probably see this term handles the effects
>of runoff and deep percolation.
What is the technical difference between application and irrigation efficiency?
dean
********************************************************
Dean Reynolds
Associate Land and Water Use Analyst
California Department of Water Resources
3251 S Street
Sacramento, Ca. 95816
916-227-7602
916-227-7600 Fax
dreynold@water.ca.gov
<------------------------------>
Date: Thu, 19 Sep 1996 21:55:56 GMT
From: Jean Piaget .<.henri@ilink.nis.za.>.
Subject: Re: Water use efficiency (reply from F. Lamm)
At 09:58 AM 9/19/96 -0500, you wrote:
>Jed wrote:
>In summarizing my work on a comparison of sprinkler and drip irrigation I
>often use the the term 'water use effeciency'. In several articles, water
>use effeciency is described by the ratio of water applied to crop yield.
>Does anyone know any other ways to represent 'Water Use Efficiency'?
>
>Hi all,
A seemingly simple question gives rise to many answers. This just proves
my contention that the language of irrigation is similar to that of politics
or religion-it all depends from what premise you start off.
No one has yet mentioned the "efficiency" when using saline waters for
example. Engineers like to see efficiency of systems, vide application
efficiency, agriculturalist may prefer best economic yield per unit of
water.For some it might be highest tonnage, for others highest quality.
What is your's Jed? Jean/
<------------------------------>
Date: Thu, 19 Sep 96 16:57:14 -0500
From: Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell)
Subject: Water use and economic efficiency
At Thu, 19 Sep 1996 14:47:21 -0500
Jean Piaget wrote:
>>Hi all,
>A seemingly simple question gives rise to many answers. This just proves
>my contention that the language of irrigation is similar to that of politics
>or religion-it all depends from what premise you start off.
>No one has yet mentioned the "efficiency" when using saline waters for
>example. Engineers like to see efficiency of systems, vide application
>efficiency, agriculturalist may prefer best economic yield per unit of
>water.For some it might be highest tonnage, for others highest quality.
>What is your's Jed? Jean/
Jean and trickle-l,
This question seems like prelim exams all over again. The goal of my
research is to determine the most efficient system (drip or sprinkler) to
achieve the highest yield while minimizing water losses to groundwater.
Through using an "efficiency" term, I wanted to show that reduced water
inputs from drip produced similar yield and quality under potato compared to
sprinkler.
>From the answers received on this server I was able to factor drainage into
the equation producing an even more efficient system. My next step is to
incorporate costs of installing drip or sprinkler systems over a decade or
two along with economic yield to determine the economic efficiency. Cost of
water in the 10,000 lakes state is cheap. So another question, that may not
be relavent to trickle-l, is the cost associated groundwater contamination
from deep percolation of nitrogen?
Thanks for the question Jean,
Jed
****************************************************
* Jed T. Waddell *
* Graduate Research Assistant *
* University of Minnesota *
* Department of Soil, Water, and Climate *
* St. Paul, MN 55108 *
* office (612) 625-1968 *
* fax (612) 625-2208 *
****************************************************
<------------------------------>
End of Digest
************************
Contents:
Re: AE and Irr E (reply from F. Lamm) (FLamm@oznet.ksu.edu (Freddie Lamm))
Re: Testing Soil For pH--Use of Suction Lysimetry (CondorSt@aol.com)
Re: Water use and economic efficiency (Irrometer@aol.com)
Re: Testing Soil For pH--Use of Suction Lysimetry ("J.D. Oster" .<.oster@mail.ucr.edu.>.)
Re: Testing Soil For pH--Use of Suction Lysimetry (ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>.)
Re: Testing Soil For pH--Use of Suction Lysimetry ("J.D. Oster" .<.oster@mail.ucr.edu.>.)
Efficiency Definitions (cburt@oboe.aix.calpoly.edu (Charles M. Burt))
Call for candidates (BRIAN_DOTSON@ati.org (BRIAN DOTSON))
<---------------------------------------------------------------------->
Date: 19 Sep 96 17:26:12 CDT
From: FLamm@oznet.ksu.edu (Freddie Lamm)
Subject: Re: AE and Irr E (reply from F. Lamm)
Dean wrote:
What is the technical difference between application and irrigation efficiency?
FREDDIE REPLIED:
I guess I should have known someone would ask. The terms are used
so often as being the same by just about everyone including myself,
that we often forget that the subtle differences can be
inconsequential in some cases, so either term works.
Application efficiency. Page 131 Mgmt of Farm Irr Systems.
Ea = Vs/Vf
where Vs = the volume of irrigation water needed for ET to avoid
undesirable water stress, and
Vf = volume of water delivered to the field.
Irrigation efficiency. Page 132-133 Mgmt of Farm Irr Systems
Ei = Vb/Vf
where Vb= the volume of water beneficially used.
Vb can be bigger than Vs because Vb can include water for leaching,
frost protection, crop cooling , pesticide or fertilizer
applications.
-------------------------------------------------------------------
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: Thu, 19 Sep 1996 19:23:13 -0400
From: CondorSt@aol.com
Subject: Re: Testing Soil For pH--Use of Suction Lysimetry
Dear Aron. Isn't a 1:1 paste better for comparison than a saturated paste?
Tom Lockhart
<------------------------------>
Date: Thu, 19 Sep 1996 19:30:07 -0400
From: Irrometer@aol.com
Subject: Re: Water use and economic efficiency
In a message dated 96-09-19 18:01:31 EDT, you write:
(Jed Waddell-University of Minnesota)
> So another question, that may not
>be relavent to trickle-l, is the cost associated groundwater contamination
>from deep percolation of nitrogen?
Jed: There may not be enough money to cover this tab at the point
in time when all ground water is sufficiently loaded with nitrogen to make
it unfit for human consumption.
Regards, Bill Pogue
<------------------------------>
Date: Thu, 19 Sep 1996 18:27:31 -0500
From: "J.D. Oster" .<.oster@mail.ucr.edu.>.
Subject: Re: Testing Soil For pH--Use of Suction Lysimetry
Tom: For saline-sodic soils, the higher the dilution, the higher the pH.
This is a consequence of exchange reactions which enrich the soil solution
with sodium and enrich the exchangeable cations with calcium and magnesium.
It also depends on your reference levels. If they are for a 1:1 than you
need to use a 1:1. But you cannot be sure that references for one dilution
applies to another. are all in terms of 1:1, or saturation paste, or 1:5 or
whatever than if you use the same method as the reference of At 06:13 PM
9/19/96 -0500, you wrote:
>Dear Aron. Isn't a 1:1 paste better for comparison than a saturated paste?
> Tom Lockhart
>
J.D.(Jim) Oster
Dept. of Soil & Env. Sciences
University of California
Riverside, CA 92521
Phone (909)787-5100
FAX (909)787-5522
<------------------------------>
Date: Thu, 19 Sep 1996 17:08:48 -0700 (PDT)
From: ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>.
Subject: Re: Testing Soil For pH--Use of Suction Lysimetry
Dear Tom: No, I dont think so. It depends on what you are trying to
accomplish. Plants normally take up many of nutrients from a soil that
is nearly saturated or saturated. This is seen dramatically in drip
irrigation systems, where the crop may be irrigated daily.
And depending upon the soil this could range from 1 to 1 on a very clay
or organic soil to 1:.25 (soil to water ratio) on a sandy soil. 1 to 1
extracts were devoloped in my opinion to streamline (short cut) the
procedure in the lab. For pH and salinity determinations I feel the SP
is the only way to go.
Aron
At 06:14 PM 9/19/96 -0500, you wrote:
>Dear Aron. Isn't a 1:1 paste better for comparison than a saturated paste?
> Tom Lockhart
>
>
<------------------------------>
Date: Fri, 20 Sep 1996 10:19:18 -0500
From: "J.D. Oster" .<.oster@mail.ucr.edu.>.
Subject: Re: Testing Soil For pH--Use of Suction Lysimetry
A given location in the soil can have different pH values because the method
of measurement affects the pH obtained. In the soil within the rootzone, the
partial pressure of carbon dioxide (Pco2)is higher than in the atmosphere.
Within dense root systems, Pco2 levels as high as 0.10 atmospheres are
possible, particularly in the lower portion of the root zone. If the pH
could be measured within the soil, its value could be 1 unit lower than
measured in the laboratory on the same soil.
The method of measurement poses problems in the laboratory as well. Make a
paste and insert the electrodes in the paste, and measure the pH. Extract a
water sample from the same paste and insert the electrodes into the sample
and measure the pH. Often the two pH readings will be different by 0.2 to
0.5 pH units. Different junction potentials within the paste and within the
extracted water sample in addition to outgassing of CO2 from the water
during the extraction process are two factors which can change the pH.
If you know the method used to establish the pH criteria, the same method
should be used to test the soil. If the methods used to establish the
criteria are not known, than whatever is used in the laboratory will provide
a relative value which people will interpret. The interpretation will have
more value if the same method is used in all cases. Call it the 'experience'
factor.
My interpretation of pH values reported by different laboratories is that
they provide information which is within +/- 0.3 pH units of what another
laboratory would obtain, or witin 1 pH unit of what was the case in the soil
at the time of sampling. pH can not be measured with the same precicion or
accuracy as ECe, or the ionic composition of an extract, at whatever soil
water content is used to obtain the water sample. 07:12 PM 9/19/96 -0500,
you wrote:
>Dear Tom: No, I dont think so. It depends on what you are trying to
accomplish. Plants normally take up many of nutrients from a soil that is
nearly saturated or saturated. This is seen dramatically in drip
irrigation systems, where the crop may be
> irrigated daily.
>
>And depending upon the soil this could range from 1 to 1 on a very clay or
organic soil to 1:.25 (soil to water ratio) on a sandy soil. 1 to 1
extracts were devoloped in my opinion to streamline (short cut) the
procedure in the lab. For pH and salinity
> determinations I feel the SP is the only way to go.
>
>Aron
>
>
>At 06:14 PM 9/19/96 -0500, you wrote:
>>Dear Aron. Isn't a 1:1 paste better for comparison than a saturated paste?
>> Tom Lockhart
>>
>>
>
>
J.D.(Jim) Oster
Dept. of Soil & Env. Sciences
University of California
Riverside, CA 92521
Phone (909)787-5100
FAX (909)787-5522
<------------------------------>
Date: Fri, 20 Sep 1996 09:56:54 -0700
From: cburt@oboe.aix.calpoly.edu (Charles M. Burt)
Subject: Efficiency Definitions
The Task Committee on Irrigation Efficiency and Uniformity, of the Water
Resources Division of the American Society of Civil Engineers, recently
submitted its revised paper to ASCE for publication in the Irrigation and
Drainage Journal.
The paper is called:
IRRIGATION PERFORMANCE MEASURES-
EFFICIENCY AND UNIFORMITY
Authors:
C.M. Burt,
A.J. Clemmens,
T.S. Strelkoff,
K.H. Solomon,
R.D. Bliesner,
L.A. Hardy,
T.A. Howell,
(Members ASCE); and
D.E. Eisenhauer
I have copies just a small portion of the paper into this message for your
information. The whole paper is about 50 pages long.
.c1.PERFORMANCE INDICATOR DEFINITIONS
Partitioning of applied irrigation water underlies the evaluation
of certain performance indicators, notably, efficiencies. Expressed as
percentages, these are fractions of the irrigation-water volume that are
destined for certain functions. Certain of these efficiencies are
impossible to define without careful specification of subject region and
time period. Others, by virtue of built-in assumptions, can avoid these
issues. The different efficiencies have different purposes and should be
carefully differentiated.
Other indicators are more properly expressed as ratios, and address
concepts such as uniformity of water distribution within a field. A
summary of various performance indicators is found in Table 1.
.c2.Irrigation Efficiency, IE
The definition of Irrigation Efficiency, IE , is
IE=3D (vol. irrigation water beneficially used)/( vol. irrig. water applied =
-
=90 storage irrig. water) x 100% (1)
The denominator in Equation (1) represents the total volume
(beneficial plus non-beneficial uses) of irrigation water which leaves the
boundaries (outflow =3D applied - =90 storage). These volumes leave within =
a
specified time interval (e.g., interval from just before an irrigation to
just before the next irrigation, or, possibly, an entire season). If at
the end of the time period the water contained within the designated region
is the same as it was at the start, =90 storage of irrigation water =3D 0, a=
nd
all of the water applied has left the region-in crop ET, runoff, deep
percolation, etc. In this way, water temporarily stored in the root zone
for use outside the specified time interval is not counted-neither adding
to the beneficial uses nor subtracting from them; it remains neutral until
such time as it leaves the subject area, one way or another.
The phrase irrigation water excludes water applied naturally to the
crop, natural precipitation or rise in the water table, for example. It is
possible, without loss of generality, to replace volume, in numerator and
denominator, by depth, with the understanding that depth is simply volume
divided by area (of field, farm, project, etc.). The relationship between
IE and beneficial and non-beneficial uses is illustrated in Figure 8.
The most common misuse of IE is the improper definition of
beneficial uses. On the one hand, theoretical beneficial uses are often
cited instead of actual beneficial uses. On the other, water which
satisfies several beneficial uses (e.g., both frost protection and seed
germination may become available to satisfy plant ET) should not be double
counted. These misuses of IE do not negate its importance in reflecting
the needs of a sustainable, viable irrigated agriculture, but merely
underscore the care with which the terms should be evaluated.
.c2.Application Efficiency, AE
The Irrigation Efficiency, Irrigation Sagacity, and Irrigation
Consumptive Use Coefficient terms are, in principal, difficult to evaluate
rapidly, and require a detailed inventory and quantification of the
ultimate (not projected or anticipated) destinations and uses of irrigation
water which was applied at some earlier date. Yet it is necessary at times
to plan for the future, and it is often necessary to judge the performance
of an irrigation system in the field, when the matter revolves not about
the issue of what the plant needs in fact are, but about how well, or
efficiently, the system satisfies a perceived need (e.g., target depth).
The matter is resolved through introduction of another efficiency
term, Application Efficiency, AE, which is based on the concept of meeting
a target irrigation depth for that event. This separates the issues of
establishing the beneficial or prudent value for the target depth from the
issue of how well the irrigation system meets a given target depth. AE is
used to estimate what happens during a single irrigation event, even though
the water has not yet been used for example, for ET. The chosen target
depth may be the Soil Moisture (water) Deficit, SMD, or some smaller amount
to accommodate potential rainfall. It may contain a desired depth of
reclamation water, or it may contain a maintenance leaching fraction as
well as the SMD. In any event,
AE=3D (avg. depth of irrig. water contributing to target/( avg. depth of
irrig. water applied) x 100% (6)
This updated definition departs from the previous AE definition
(ASCE, 1978) in that the previous definition only considered SMD, and did
not include any water for leaching or other perceived beneficial uses. For
this special case,
AE(SMD)=3D (avg. depth of water contributing to the SMD)/( avg. depth of
irrigation water applied) x 100% (7)
In contrast to the definitions of Irrigation Efficiency and
Irrigation Sagacity, in which it is understood that the beneficial uses are
not necessarily uniformly distributed over a field, implicit in this
definition of Application Efficiency is the assumption that the target
depth is uniform over the subject area (or that special management such as
precision irrigation is available to match known, non-uniform targets).
=46urthermore, a stated requirement eliminates the necessity for specifying =
a
time period in the definition. With Application Efficiency referring to a
single event with an identified target depth, rather than to a period of
time over which benefits are realized, changes in soil water storage (which
are implied in the numerator) do not explicitly appear in the definition.
If the requirement is just equal to the sum of the expected
beneficial uses, Application Efficiency (AE) provides an estimate for the
potential Irrigation Efficiency (i.e. what the IE will be if the expected
benefits occur, and if the beneficial uses are uniform over the field). AE
will typically be higher than IE since there is often unavoidable,
non-beneficial evaporation (e.g., sprinkler and excess soil evaporation).
=46urthermore, water applied with a high AE may not be beneficially used if
the timing is poor (e.g., at the end of the growing season when crop ET
drops to zero).
The On-Farm Committee (ASCE, 1978) presented the concept of
low-quarter application efficiency (AElq) to account for irrigation water
that is stored within the root zone after an irrigation event, but that may
not be useful in the future because of irrigation non-uniformity. AElq
uses the low-quarter depth divided by the average depth applied as the
measure of irrigation performance. The rationale for this is that if
irrigations are scheduled to avoid crop-water stress in the low quarter
area of the field, and it is assumed that the distribution of water from
successive irrigations is similar, then the areas that received more than
the low-quarter depth in the previous irrigation will not be able to
utilize that water before receiving more. In this case, we suggest that AE
be used, rather than AElq, and that the requirement be changed to the
low-quarter depth. On the other hand, if the plants in the low quarter are
significantly stressed between irrigations, whether by accident or by
intentional deficit irrigation, then this adjustment is not appropriate,
and no adjustment or adjustment based on some larger field area may be
appropriate. The significance of AElq is somewhat uncertain for a given
irrigation, since it depends upon the intent of the irrigation and upon
future scheduling.
.c2.Potential Application Efficiency, PAE, PAElq
The concept of potential application efficiency, PAE, is also
useful in measuring the performance of a system for a single irrigation
event. PAE is based on the concept that the application could be
terminated at such time that the target would be just met by the average of
the lowest values in the irrigation infiltration distribution. Deep
percolation losses would then be held to a minimum, and the application
efficiency would be at a maximum without significant under-irrigation.
Deep percolation would be minimized, and due only to non-uniformity of the
distribution.
=0C PAE is thus a reasonable criterion for computing a water order to
satisfy a given requirement, provided the average of the lowest values is
satisfactory from an agronomic standpoint. A small fraction of the field
remains under-irrigated, but, the requirement is essentially satisfied in
the field. Hence, the characterization, potential, is assigned to the
application efficiency. As in the case of DU, this concept cannot be
quantified until the lowest values in the distribution have been
characterized by a specified fraction of field area. Again, as in the case
of DU, current practice supports the value 1/4. As noted earlier, if the
variation of infiltrated depth with field area were linear, this would
imply that 1/8 of the field remains (slightly) under-irrigated. Thus, the
potential application efficiency of the low quarter, PAElq, for a single
event is defined
PAElq =3D (avg depth of irrig water contributing to target)/(avg dpth of
irrig wtr appl that dlq =3D target) x 100% (8)
Using PAElq, one can determine the gross amount of water to apply;
note that the denominators of DUlq and PAElq differ, in essence, by the
amount of surface losses (uncollected runoff and evaporation). For
irrigation scheduling purposes, with a target depth at the average
low-quarter value, PAElq can be estimated in advance if the surface losses
are accurately estimated (the estimate is usually a little high), as
PAElq =89 DUlq x (100 - % surface losses) (9)
=0Cwhere surfaces losses are composed of non-beneficial evaporation during
the irrigation, spray drift, and uncollected surface runoff. This
approximation is usually better for pressurized irrigation systems, where
DUlq and % surface losses do not change as much with application depth as
they do for surface irrigation systems, where they can change dramatically.
It follows that, the gross irrigation water required for an
irrigation event with proper irrigation scheduling can be estimated as
Gross average depth to apply =89 Target depth x (100/ PAElq)
(10)
Charles M. Burt, P.E., Ph.D.
Professor and Director
Irrigation Training and Research Center (ITRC)
BioResource and Agricultural Engineering Dept.
California Polytechnic State University (Cal Poly)
San Luis Obispo, CA 93407
ph: 805-756-2379
=46AX: 805-756-2433
e-mail: cburt@oboe.calpoly.edu
<------------------------------>
Date: Fri, 20 Sep 1996 14:44:46 -0400
From: BRIAN_DOTSON@ati.org (BRIAN DOTSON)
Subject: Call for candidates
Small-Scale Mechanized Irrigation Project Director
Not-for-profit international development organization, seeks
candidates for a Project Director of a small-scale
mechanized irrigation project in Niger, West Africa. The
goal of this project is to identify, test, adapt, and promote
the commercial dissemination of several low-cost motorized
pumps and wells to small-scale farmers. The Project
Director will be based in Niamey, Niger for 3 years and will
have overall operational responsibility for the project.
Qualified candidates for the position must have:
- previous project management experience with
an agriculturally related development project in
a Sahelian country in West Africa;
- significant professional experience in the
marketing and commercialization of productive
agricultural equipment, preferably irrigation-
related; and,
- oral and written proficiency in French and
English.
Preferred candidates will have:
- an advanced degree in a related discipline;
- experience in the design, testing, and
operation of small-scale, pump-based irrigation
schemes; and,
- fluency in French and English.
Salary commensurate with experience. Other benefits
include: health and evacuation insurance and allowances
for transportation and shipment of household effects.
Interested candidates must respond before October 15,
1996 by sending a current CV along with a cover letter
summarizing relevant experience and salary requirements
to the attention of BD at the email address or fax # below.
NO TELEPHONE INQUIRIES WILL BE CONSIDERED.
Only those candidates under serious consideration will
receive a response. Responses may be sent via email to
africa@ati.org or by fax to (202) 293 4598.
<------------------------------>
End of Digest
************************
Contents: Manufacturers of trickle irrigation tubings (Farhad Fassihi .<.farhad@behzad.ntu.ac.uk.>.) <---------------------------------------------------------------------->
Date: Mon, 23 Sep 1996 09:41:22 +0100 From: Farhad Fassihi .<.farhad@behzad.ntu.ac.uk.>. Subject: Manufacturers of trickle irrigation tubings I am looking for the name and addresses of manufacturers of PE trickle-irrigation tubings (specially those in Europe). Has anybody there with some info in that regard? Also any information about the sources of information about its manufacturing techniques is appreciated. Many thanks F.Fassihi, Polymer Engineering Centre, The Nottingham Trent University UK. <------------------------------>
End of Digest ************************
Contents: iron-phosphate scale (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.) <---------------------------------------------------------------------->
Date: Tue, 24 Sep 1996 10:19:27 -0500 (EST) From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>. Subject: iron-phosphate scale I have observed the formation of iron-phosphate scale in micro irrigation systems using groundwater. The water source has both iron and phosphate at fairly high levels and pH runs from 5.5 to 6.5. Does anyone have ideas on what might be the best treatment strategy for the prevention of emitter plugging? <------------------------------>
End of Digest ************************
Contents:
Re: iron-phosphate scale ("J.D. Oster" .<.oster@mail.ucr.edu.>.)
<---------------------------------------------------------------------->
Date: Tue, 24 Sep 1996 10:18:16 -0500
From: "J.D. Oster" .<.oster@mail.ucr.edu.>.
Subject: Re: iron-phosphate scale
Don: For iron, sulfurous acid (not sulfuric acid) can make iron soluble. It
has been used to remove iron precipitates from subsurface drain lines. The
first use I'm aware of was by Dr. William Spencer in Florida when they
bubbled sulphur dioxide gas into drain lines that were kept full of water to
remove iron coatings. That was done about 40 years ago. Spencer (Adjunct
Professor, Emeritus) lives in Riverside CA, and his phone number is 909 369
4846.
Using a sulphur burner may be a possibility to prevent iron precipitation in
the first place. A sulphur burner generates sulphur dioxide gas -- so one
would somehow inject the gas into the water. But, the pH of the water can go
down if too much is applied. There are sulphur burners used in California,
but I don't have the business address. Maybe Blake Sanden does.
As for phosphate: I'm forwarding this reply to Dr. Chris Amrhein
(chrisa@ucrac1.ucr.edu) in our Department, because he may have some ideas.
Perhaps some control can be achieved by proper control and selection of
injected fertilizer solutions. Since calcium phosphate is very insoluble,
any injection of calcium could make the problem worse.
At 09:24 AM 9/24/96 -0500, you wrote:
> I have observed the formation of iron-phosphate scale in micro irrigation
>systems using groundwater. The water source has both iron and phosphate at
>fairly high levels and pH runs from 5.5 to 6.5. Does anyone have ideas on
>what might be the best treatment strategy for the prevention of emitter
>plugging?
>
>
>
>
>
J.D.(Jim) Oster
Dept. of Soil & Env. Sciences
University of California
Riverside, CA 92521
Phone (909)787-5100
FAX (909)787-5522
<------------------------------>
End of Digest
************************
Contents: Re: TRICKLE-L digest 601 (TPiatkowsk@aol.com) <---------------------------------------------------------------------->
Date: Thu, 26 Sep 1996 00:36:54 -0400 From: TPiatkowsk@aol.com Subject: Re: TRICKLE-L digest 601 Jim, With regards to the emitter plugging and general maintenance of drip systems utilizing simalar qualities of water, I would suggest the use of a phosphonate material such as Agri-Guard or Sure Flow. They are not pH dependent and are the most effective materials we have found to address iron. We have been successful in addressing problems similar to what you describe. If you want more information please e-mail me and I would be glad to provide you with additional material. Tom Ag H2O <------------------------------>
End of Digest ************************
Contents: Re: iron-phosphate scale (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.) Re: iron-phosphate scale (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.) Pipes in Florida (Manrique Brenes .<.mjbrenes@ucdavis.edu.>.) Re: Pipes in Florida (momary@tifton.cpes.peachnet.edu) <---------------------------------------------------------------------->
Date: Thu, 26 Sep 1996 11:00:11 -0500 (EST) From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>. Subject: Re: iron-phosphate scale At 10:23 AM 9/24/96 -0500, you wrote: >Don: For iron, sulfurous acid (not sulfuric acid) can make iron soluble. It >has been used to remove iron precipitates from subsurface drain lines. The >first use I'm aware of was by Dr. William Spencer in Florida when they >bubbled sulphur dioxide gas into drain lines that were kept full of water to >remove iron coatings. That was done about 40 years ago. Spencer (Adjunct >Professor, Emeritus) lives in Riverside CA, and his phone number is 909 369 >4846. > >Using a sulphur burner may be a possibility to prevent iron precipitation in >the first place. A sulphur burner generates sulphur dioxide gas -- so one >would somehow inject the gas into the water. But, the pH of the water can go >down if too much is applied. There are sulphur burners used in California, >but I don't have the business address. Maybe Blake Sanden does. > >As for phosphate: I'm forwarding this reply to Dr. Chris Amrhein >(chrisa@ucrac1.ucr.edu) in our Department, because he may have some ideas. >Perhaps some control can be achieved by proper control and selection of >injected fertilizer solutions. Since calcium phosphate is very insoluble, >any injection of calcium could make the problem worse. > > >At 09:24 AM 9/24/96 -0500, you wrote: >> I have observed the formation of iron-phosphate scale in micro irrigation >>systems using groundwater. The water source has both iron and phosphate at >>fairly high levels and pH runs from 5.5 to 6.5. Does anyone have ideas on >>what might be the best treatment strategy for the prevention of emitter >>plugging? >> >> >> >> >> >J.D.(Jim) Oster >Dept. of Soil & Env. Sciences >University of California >Riverside, CA 92521 > >Phone (909)787-5100 >FAX (909)787-5522 > > <------------------------------>
Date: Thu, 26 Sep 1996 11:02:09 -0500 (EST) From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>. Subject: Re: iron-phosphate scale Jim: Thanks for your response. Perhaps I was not clear in my description of the problem. The water source is groundwater, pH is already fairly low (5.5 to 6.5), and Fe levels are 3-4 mg/l. This is not an uncommon condition in our area. What seems to have compounded the problem is the high P levels in the groundwater (3-5 mg/l). No phosphorus fertilizer has been injected. We can remove the iron by oxidation and filtration; however, I am not sure what problems we will have with the remaining phosphate. The largest constituent in the plugging material is P. We want to prevent scale not remove it! At 10:23 AM 9/24/96 -0500, you wrote: >Don: For iron, sulfurous acid (not sulfuric acid) can make iron soluble. It >has been used to remove iron precipitates from subsurface drain lines. The >first use I'm aware of was by Dr. William Spencer in Florida when they >bubbled sulphur dioxide gas into drain lines that were kept full of water to >remove iron coatings. That was done about 40 years ago. Spencer (Adjunct >Professor, Emeritus) lives in Riverside CA, and his phone number is 909 369 >4846. > >Using a sulphur burner may be a possibility to prevent iron precipitation in >the first place. A sulphur burner generates sulphur dioxide gas -- so one >would somehow inject the gas into the water. But, the pH of the water can go >down if too much is applied. There are sulphur burners used in California, >but I don't have the business address. Maybe Blake Sanden does. > >As for phosphate: I'm forwarding this reply to Dr. Chris Amrhein >(chrisa@ucrac1.ucr.edu) in our Department, because he may have some ideas. >Perhaps some control can be achieved by proper control and selection of >injected fertilizer solutions. Since calcium phosphate is very insoluble, >any injection of calcium could make the problem worse. > > >At 09:24 AM 9/24/96 -0500, you wrote: >> I have observed the formation of iron-phosphate scale in micro irrigation >>systems using groundwater. The water source has both iron and phosphate at >>fairly high levels and pH runs from 5.5 to 6.5. Does anyone have ideas on >>what might be the best treatment strategy for the prevention of emitter >>plugging? >> >> >> >> >> >J.D.(Jim) Oster >Dept. of Soil & Env. Sciences >University of California >Riverside, CA 92521 > >Phone (909)787-5100 >FAX (909)787-5522 > > <------------------------------>
Date: Thu, 26 Sep 1996 23:26:27 -0700 From: Manrique Brenes .<.mjbrenes@ucdavis.edu.>. Subject: Pipes in Florida I would appreciate it if somebody could let me know how to contact a PVC pipe manufacturer in Florida. Also if anyone knowsof a web site that has a listing of US PVC pipe manufacturers it would be very useful to me. Thanks. Manrique Brenes <------------------------------>
Date: Fri, 27 Sep 1996 08:11:47 +0000 From: momary@tifton.cpes.peachnet.edu Subject: Re: Pipes in Florida Here is one PVC pipes manufacturer in Florida: Colonlial Plastics MFG. CO. 5128 W. Hanna Ave. Tampa, Florida 33614 (813) 884-2525 Date: Fri, 27 Sep 1996 01:23:25 -0500 Reply-to: .<.trickle-l@unl.edu.>. From: Manrique Brenes .<.mjbrenes@ucdavis.edu.>. To: Multiple recipients of list .<.trickle-l@unl.edu.>. Subject: Pipes in Florida I would appreciate it if somebody could let me know how to contact a PVC pipe manufacturer in Florida. Also if anyone knowsof a web site that has a listing of US PVC pipe manufacturers it would be very useful to me. Thanks. Manrique Brenes MOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMOMO Mohammad Omary Research Scientist Bio. & Ag. Engin. Dept. Tel. : (912) 386-3377 University of Georgia Fax : (912) 386-3958 748 Rainwater Rd. Tifton, Ga 31794 e-mail: momary@tifton.cpes.peachnet.edu <------------------------------>
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Contents: Re: TRICKLE-L digest 601 (oster@mail.ucr.edu) <---------------------------------------------------------------------->
Date: Sun, 29 Sep 1996 22:22:25 -0500 From: oster@mail.ucr.edu Subject: Re: TRICKLE-L digest 601 Tom: Please send info. At 11:51 PM 9/25/96 -0500, you wrote: >Jim, > >With regards to the emitter plugging and general maintenance of drip systems >utilizing simalar qualities of water, I would suggest the use of a >phosphonate material such as Agri-Guard or Sure Flow. They are not pH >dependent and are the most effective materials we have found to address iron. > >We have been successful in addressing problems similar to what you describe. >If you want more information please e-mail me and I would be glad to provide >you with additional material. > >Tom >Ag H2O > > <------------------------------>
End of Digest ************************
Contents: Re: TRICKLE-L digest 601 (oster@mail.ucr.edu) Re: topo map (Dripigate@aol.com) Re: iron-phosphate scale (ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>.) <---------------------------------------------------------------------->
Date: Sun, 29 Sep 1996 22:39:13 -0500 From: oster@mail.ucr.edu Subject: Re: TRICKLE-L digest 601 Tom: Please send info. At 11:51 PM 9/25/96 -0500, you wrote: >Jim, > >With regards to the emitter plugging and general maintenance of drip systems >utilizing simalar qualities of water, I would suggest the use of a >phosphonate material such as Agri-Guard or Sure Flow. They are not pH >dependent and are the most effective materials we have found to address iron. > >We have been successful in addressing problems similar to what you describe. >If you want more information please e-mail me and I would be glad to provide >you with additional material. > >Tom >Ag H2O > > <------------------------------>
Date: Mon, 30 Sep 1996 01:07:32 -0400 From: Dripigate@aol.com Subject: Re: topo map Yossi look at the coservation service for your maps, under the old Federation of Rhodesia and NYasaland most farning land in the three countries was mapped. <------------------------------>
Date: Mon, 30 Sep 1996 17:12:06 -0700 (PDT) From: ARON QUIST .<.stanworth@MAIL.TELIS.ORG.>. Subject: Re: iron-phosphate scale Dear Don: I do not know if I have a solution, but I can relate an experience that I had with a plugging drip tape once. A consultant brought in a tape with a greenish white ppt inside the line to my lab. We removed a sample from the tape and tried to wet digest it with acid. This did not work and we went alkaline with sodium hydroxide. The material went into solution. In the final analysis the material may have been a ammonium poly phophate injected into the system. Our sugggestion was to try injecting a potassium hydroxide fertilzer into the system to help unplug the lines. This is a common fertilizer. Caution should be used with this product on established fields. We have not had a follow up on this. good luck, Aron At 10:09 AM 9/26/96 -0500, you wrote: > >Jim: Thanks for your response. Perhaps I was not clear in my description >of the problem. The water source is groundwater, pH is already fairly low >(5.5 to 6.5), and Fe levels are 3-4 mg/l. This is not an uncommon condition >in our area. What seems to have compounded the problem is the high P levels >in the groundwater (3-5 mg/l). No phosphorus fertilizer has been injected. > >We can remove the iron by oxidation and filtration; however, I am not sure >what problems we will have with the remaining phosphate. The largest >constituent in the plugging material is P. We want to prevent scale not >remove it! > > >At 10:23 AM 9/24/96 -0500, you wrote: >>Don: For iron, sulfurous acid (not sulfuric acid) can make iron soluble. It >>has been used to remove iron precipitates from subsurface drain lines. The >>first use I'm aware of was by Dr. William Spencer in Florida when they >>bubbled sulphur dioxide gas into drain lines that were kept full of water to >>remove iron coatings. That was done about 40 years ago. Spencer (Adjunct >>Professor, Emeritus) lives in Riverside CA, and his phone number is 909 369 >>4846. >> >>Using a sulphur burner may be a possibility to prevent iron precipitation in >>the first place. A sulphur burner generates sulphur dioxide gas -- so one >>would somehow inject the gas into the water. But, the pH of the water can go >>down if too much is applied. There are sulphur burners used in California, >>but I don't have the business address. Maybe Blake Sanden does. >> >>As for phosphate: I'm forwarding this reply to Dr. Chris Amrhein >>(chrisa@ucrac1.ucr.edu) in our Department, because he may have some ideas. >>Perhaps some control can be achieved by proper control and selection of >>injected fertilizer solutions. Since calcium phosphate is very insoluble, >>any injection of calcium could make the problem worse. >> >> >>At 09:24 AM 9/24/96 -0500, you wrote: >>> I have observed the formation of iron-phosphate scale in micro irrigation >>>systems using groundwater. The water source has both iron and phosphate at >>>fairly high levels and pH runs from 5.5 to 6.5. Does anyone have ideas on >>>what might be the best treatment strategy for the prevention of emitter >>>plugging? >>> >>> >>> >>> >>> >>J.D.(Jim) Oster >>Dept. of Soil & Env. Sciences >>University of California >>Riverside, CA 92521 >> >>Phone (909)787-5100 >>FAX (909)787-5522 >> >> > > > <------------------------------>
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