TRICKLE-L digests for JULY 1996

To AGRONOMY homepage @ SunSITE

From ab4el@ab4el.com Thu Aug 1 00:00 EDT 1996
From: Stephen Modena <modena@SunSITE.unc.edu>
Message-Id: <9608010001.ab4el@ab4el.com>
Subject: TRICKLE-L LOG9607
Date: Thu, 1 Aug 1996 00:01:00 -0400 (EDT)

This is the compendium of TRICKLE-L digests for July 1996.

It was prepared from the daily digest mailings. Some digests
may be missing, because occasional mailings are lost en route.



From root@crcnis1.unl.edu Fri Jul 5 20:33 EDT 1996
Date: Fri, 5 Jul 1996 19:21:54 -0500
Message-Id: .<.199607060021.AA00682@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 536

Contents:
SDI question  (Richard Mead .<.rmead@cybergate.com.>.)

<---------------------------------------------------------------------->

Date: Sat, 6 Jul 1996 00:31:00 GMT From: Richard Mead .<.rmead@cybergate.com.>. Subject: SDI question Basant Maheshwari is one of the original subscribers to Trickle-L. He is touring the US and is having trouble logging onto Trickle-L. He has asked me to forward this comment/question to group. R. Mead Trickle-L owner/manager +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Recently I visited a farm near Altus (Oklahoma State, USA) with subsurface drip irrigation. I thought I will share my this experience of this visit with the members on the list. The farmer is growing cotton and the total area under SDI is about 700 acres. Water for SDI is drawn from a nearby canal and is cleaned through three fine sand filters and treated with alum to avoid any clogging problem. The whole system is computerised for the amount and timing of irrigation. There is also some arrangement for injection of fertiliser into the water. The system is in the first year of its operation. During the disucssion, the farmer mentioned that SDI has been very beneficial to him in reducing the labor requirement and getting uniform germination of seeds. The amount of water used so far has also reduced considerably, but he thinks that water savings through SDI will be one of his last consideations in adopting SDI for his farm (This is inspite of water being relatively scarce in this area of Oklahoma). Other farmers in the area are keenly watching the adventure of this farmer and may be one day some of them will also follow him. Is water saving important and justifable factor for selecting SDI in a given area? What do other people think on this question? Basant Maheshwari <------------------------------>
End of Digest ************************


From ab4el@ab4el.com Sun Jul 7 00:00 EST 1996
Date: Sun, 7 Jul 1996 00:01:00 -0600
Message-Id: .<.199607070001.ab4el@ab4el.com.>.
From: ab4el@ab4el.com
Subject: TRICKLE-L digest 537 was NOT received

TRICKLE-L digest 537 was NOT received

<---------------------------------------------------------------------->



From root@crcnis1.unl.edu Mon Jul 8 22:19 EDT 1996
Date: Mon, 8 Jul 1996 21:07:30 -0500
Message-Id: .<.199607090207.AA09218@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 538

Contents:
Re: SDI question  (Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell))

<---------------------------------------------------------------------->

Date: Mon, 8 Jul 96 21:04:53 -0500 From: Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell) Subject: Re: SDI question Dear trickle-l subscribers, On 7-5 Richard Mead wrote: > >Is water saving important and justifable factor for selecting SDI in a given >area? What do other people think on this question? > Of course we all know saving water is important but whether it is justifiable is to be decided by policy makers and politicians. To give an example of the water savings: One of our papers to be presented at the 1996 meetings of The American Society of Agricultural Engineers International in Phoenix compares sprinkler and drip irrigation on potato (Russett Burbank) yield in central Minnesota. Sprinkler treatments had irrigation triggered when 30 or 60% of the available water holding capacity was used by the crop. Drip (both surface and buried at 30 cm) irrigations were triggered by tensiometers when matric potential was -30kPa. In 1994 water was applied by drip to refill the soil to field capacity (approx 10 cm per irrigation) while in 1995 only 1 mm of water was applied per drip irrigation. Results of total water applied in all treatmens are as follows: _________________________________________________________________ Treatment 1994(cm) 1995(cm) 30% Deficit Trigger 20.2 15.5 60% Deficit Trigger 20.7 9.6 Surface Drip 11.3 2.0 Buried Drip 10.6 1.8 __________________________________________________________________ (I hope this table is readable) Total tuber yield was not significantly different in 1994. Surface drip yield was highest in 1995 and was significantly higher than the 30% deficit trigger sprinkler treatment. The buried drip and 60% deficit treatment yields in 1995 were not different from other treatments. So, is a 47% savings in 1994 and an 88% savings of water in 1995 justifiable? Sincerely, Jed Waddell Jed T. Waddell Graduate Research Assistant University of Minnesota Department of Soil, Water, and Climate St. Paul, MN 55108 (612) 625-1968 jwaddell@soils.umn.edu <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Tue Jul 9 22:31 EDT 1996
Date: Tue, 9 Jul 1996 21:18:57 -0500
Message-Id: .<.199607100218.AA01544@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 539

Contents:
INTRODUCTION AND QUESTION (Rod Ennor .<.rodennor@parker.inter.net.il.>.)
Re: Jed Waddell (dreynold@cd-eso.water.ca.gov)
Re: Jed Waddell (Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell))
GROUNDWATER Mailing List (kenbannister@groundwater.com (Kenneth E. Bannister))

<---------------------------------------------------------------------->

Date: Tue, 9 Jul 1996 18:29:51 +0400 From: Rod Ennor .<.rodennor@parker.inter.net.il.>. Subject: INTRODUCTION AND QUESTION AS I HAVE BEEN READING TRICKLE-L FOR A FEW WEEKS I THOUGHT IT WAS TIME TO INTRODUCE MYSELF. MY NAME IS ROD ENNOR AND I AM AN EX AUSTRALIAN LIVING ON A KIBBUTZ ON THE NORTHERN EDGE OF THE NEGEV DESERT IN ISRAEL. 1. MY AFFILIATION WITH DRIP IRRIGATION IS SIMPLY THAT ON MY KIBBUTZ WE USE DRIP IRRIGATION FOR NEARLY EVERY CROP GROWN. ..A MUST.. 2. CURRENTLY WE USE DRIPPERS FOR COTTON, JOJOBA, CHICK PEES AND SUNFLOWERS. 3. THE CURRENT CROPS ARE ALL IRRIGATED WITH SURFACE DRIPPERS. 4. THE ONLY PROBLEM THAT WE HAVE HERE IS THE LACK OF WATER. 5. N, P AND K DETAILS TO FOLLOW. 6. WITHOUT DRIP IRRIGATION IT WOULD BE IMPRACTICAL TO FARM IN THIS AREA OF ISRAEL. THE TEMPERATURE TODAY WAS 40 DEG C. AT NOON, AND HAS BEEN LIKE THIS FOR THE LAST WEEK. ANY OTHER FORM OF IRRIGATION IS JUST NOT FEASABLE. 7. WATER QUALITY IS NOT NORMALLY A PROBLEM AS WE ALWAYS MAINTAIN OUR FILTER SYSTEM AT THE OPTIMUM CONDITION. 8. TO FOLLOW. 9. NO RODENT DAMAGE BUT WE FIND THAT THE VALVES ETC ARE STOLEN ON A REGULAR BASIS. 10. DESIGNED PERFECTLY AND THEY ALWAYS WORK PERFECTLY. (WELL, NEARLY ALWAYS UNLESS I HAPPEN TO BE DRIVING THE TRACTOR) 11. I FOUND OUT ABOUT THE LIST BY ACCIDENT. NOTE... I HAVE NOTICED SEVERAL QUESTIONS IN THE ARCHIVES REGARDING THE USE OF RECYCLED WATER FOR USE IN SDI AND SSDI. WE USE SECONDARY WATER ON PART OF THE JOJOBA CROP AND HAVE BEEN DOING SO FOR SEVERAL YEARS. IF ANYONE WOULD LIKE MORE INFORMATION I WOULD BE HAPPY TO OBLIGE. QUESTION... IN ISRAEL THERE ARE 2 SCHOOLS OF THOUGHT ON THE DISTANCE BETWEEN ROWS WHEN PLANTING CORN. ONE IS THE TRADITIONAL 80CM AND THE OTHER IS A HIGH DENSITY PLANTING OF 30CM, GIVING A PLANT DENSITY OF 14 PLANTS TO THE SQUARE METER. (25CM BETWEEN PLANTS AND 30CM BETWEEN ROWS) WOULD ANYONE CARE TO MAKE A COMMENT ON THE ADDITIONAL WATER DEMAND DURING A HOT SUMMER PLUS THE EFFECT THAT THIS MIGHT HAVE ON THE SOIL N LEVELS POST HARVEST. ROD ENNOR <------------------------------>
Date: Tue, 9 Jul 96 08:17:58 PDT From: dreynold@cd-eso.water.ca.gov Subject: Re: Jed Waddell Jed Waddle wrote: --- Begin Included Message --- One of our papers to be presented at the 1996 meetings of The American Society of Agricultural Engineers International in Phoenix compares sprinkler and drip irrigation on potato (Russett Burbank) yield in central Minnesota. Sprinkler treatments had irrigation triggered when 30 or 60% of the available water holding capacity was used by the crop. Drip (both surface and buried at 30 cm) irrigations were triggered by tensiometers when matric potential was -30kPa. In 1994 water was applied by drip to refill the soil to field capacity (approx 10 cm per irrigation) while in 1995 only 1 mm of water was applied per drip irrigation. Results of total water applied in all treatmens are as follows: _________________________________________________________________ Treatment 1994(cm) 1995(cm) 30% Deficit Trigger 20.2 15.5 60% Deficit Trigger 20.7 9.6 Surface Drip 11.3 2.0 Buried Drip 10.6 1.8 __________________________________________________________________ (I hope this table is readable) Total tuber yield was not significantly different in 1994. Surface drip yield was highest in 1995 and was significantly higher than the 30% deficit trigger sprinkler treatment. The buried drip and 60% deficit treatment yields in 1995 were not different from other treatments. So, is a 47% savings in 1994 and an 88% savings of water in 1995 justifiable? Sincerely, Jed Waddell Jed T. Waddell Graduate Research Assistant University of Minnesota Department of Soil, Water, and Climate St. Paul, MN 55108 (612) 625-1968 jwaddell@soils.umn.edu -- End Included Message --- Mr. Waddell, I realize that your paper will contain much more information than is contained here. I am left with a few questions? What is the average total ET in your area for potatoes? Were the plants stressed in your study? Or is this an example of getting the right amount of water to the plant in the most efficient way? Dean Reynolds California Department of Water Resources <------------------------------>
Date: Tue, 9 Jul 96 14:06:01 -0500 From: Jed T Waddell .<.wadde002@maroon.tc.umn.edu.>. (Jed Waddell) Subject: Re: Jed Waddell On July 9 Dean Reynold asked: >>What is the average total ET in your area for potatoes? Generally, between 30 and 40 cm is tha average ET for potato in Central Minnesota. In this region average annual rainfall (~60 cm) exceeds water use but coarse soils with rapid drainage and associated low water holding capacities necessitate supplamental irrigation. Our premise was to design an irrigation system to apply water directly to the root zone leaving ample space for rainfall to be stored. Previously, an irrigator would sprinkler apply water to fill the soil to field capacity; in the event of rain on the next day water, along with solutes (particularly nitrate), would be lost to subsurface water reserviors. Dean Reynolds also asked: >>Were the plants stressed in your study? Or is this an example of getting >>the right amount of water to the plant in the most efficient way? I don't think the plants were stressed especially in 1994 because growing conditions were excellent with tuber yields averaging 53 Mg/ha. In 1995, however, high temperatures were suspected to reduce stolon formation early in the growing season thereby decreasing yields (average 1995 tuber yield= 35 Mg/ha). Growers in the area used Penman PET values to initiate sprinkler irrigation and during the warm period while plants were small, the center pivots never (almost never) stopped going around.] Hope I answered your questions, Jed **************************************************** * Jed T. Waddell * * Graduate Research Assistant * * University of Minnesota * * Department of Soil, Water, and Climate * * St. Paul, MN 55108 * * (612) 625-1968 * **************************************************** <------------------------------>
Date: Tue, 9 Jul 1996 17:50:44 -0400 (EDT) From: kenbannister@groundwater.com (Kenneth E. Bannister) Subject: GROUNDWATER Mailing List ANNOUNCING: GROUNDWATER and GROUNDWATER-DIGEST Internet Mailing Lists Please join our global discussion group on groundwater and related topics. There are over 2100 members worldwide, from over 50 different countries. There are many USGS, EPA and Corps of Engineers members. If you have a groundwater question, this is the place to post it. ................................................................ To subscribe to GROUNDWATER send e-mail to: majordomo@ias.champlain.edu In the body of the e-mail type the command: subscribe GROUNDWATER ........................................................... For more information visit the Groundwater.Com Web Site. We hope you will join our lively discussion on this interesting topic. Apologies for the cross posting. Ken Bannister -------------------------------------------------------------- Kenneth E. Bannister President - BANNISTER RESEARCH & CONSULTING Owner - GROUNDWATER Mailing List http://www.groundwater.com KenBannister@groundwater.com Sponsor- Addison United Soccer Club - 1996 Vermont Cup Runner-Up U - 12 Olympic Development League Soccer -------------------------------------------------------------- <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Thu Jul 11 20:57 EDT 1996
Date: Thu, 11 Jul 1996 19:44:20 -0500
Message-Id: .<.199607120044.AA11449@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 540

Contents:
Re: INTRODUCTION AND QUESTION (Guy_Twombly@pno.com (Guy Twombly))

<---------------------------------------------------------------------->

Date: 12 Jul 1996 00:39:39 GMT From: Guy_Twombly@pno.com (Guy Twombly) Subject: Re: INTRODUCTION AND QUESTION Rod Ennor!!! Would you mind sending me your address I have some qustions of my own on " life on a kibbutz"? If you wouldn't mind, I how ever can't help you with the drip system as I am as new to this as you are????????????? Guy T. <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Sat Jul 13 20:43 EDT 1996
Date: Sat, 13 Jul 1996 19:32:09 -0500
Message-Id: .<.199607140032.AA07751@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 541

Contents:
Emitter question/MIF gallery/new members (rmead@cybergate.com (Richard Mead))

<---------------------------------------------------------------------->

Date: Sun, 14 Jul 1996 00:41:45 GMT From: rmead@cybergate.com (Richard Mead) Subject: Emitter question/MIF gallery/new members I recently met some Australian visitors at our laboratory. One gentlemen was a farmer who had recently purchased an SDI system for 50 acres (20 hectares). I believe it was all tape and not hardhose. He was concerned about the orientation of the emitter. The main focus of his concern was that he thought the emitters had a greater chance of getting clogged if the emitter was faced downward vs. facing up. I first told him that I had never heard that question, and just off the top of my head said that I thought it probably doesn't matter providing there is sufficient filtration upstream. Then, thinking I had just put my foot in my mouth, I mentioned that I honestly don't know the exact answer and would post the question to all Trickle-L experts out there in cyberspace. So gang, does it matter how the emitter is facing: up or down? Also, I don't think I have formally announced a new section on the Microirrigation Forum web site (http://www.cybergate.com/~rmead) yet. I have named it the Microirrigation Forum Digital Gallery. Please be sure to check it out if you haven't already. There is a small database of images related to drip/microspray issues, but I would like more input from people as to what they would like to see and/or displayed. Finally, I wanted to update everyone about 2 new subscribers. Below are responses from new Trickle-L members Jim Wright and L.G. Smith. Welcome Jim and L.G. !! Richard Mead Trickle-L owner/manager <---------------------------------------------------------------------------->
----------------------------------------- <---------------------------------------------------------------------------->
----------------------------------------- >From Jim Wright 1) Briefly, what is your affiliation with trickle/drip irrigation? > I am a small grain farmer with up to a couple of acres of U-pick >strawberries.< 2) What crops or plants do you use drip irrigation on? >Strawberries, as well as a few market garden vegetables.< 4) What problems have you encountered with drip irrigation? > Because I use surface irrigation, the tapes interfere with weeding. < 6) Have you experienced a reduction in fertilizer and/or water use? >I couldn't grow strawberries without drip irrigation, since I don't have a water source that would support sprinkler irrigation. < 7) Do you have water quality problems? If so, how do you tackle the situation? Water quality is adequate, but low lying soils would quickly develop a salinity problem if large quantities of water were used. The water is surface runoff collected in a dugout and subject to a series of algal blooms each season. I use only a fine mesh screen filter and haven't experienced serious problems with clogging. 8) How frequent do you irrigate? Many times a day or just one long session per day or several days? >Several hours at a time as required.< 9) Do you have rodent damage? If so, how do you control the problem? >Rodent damage minimal but coyotes scavenging overripe berries have done >lots of damage. I *have* had considerable rodent damage in storage, as I lift most of the drip line each fall.< 10) Are you pleased with the uniformity of your system or systems? Were they designed correctly? >It is a very simple system, using a centrigual pump, screen filters, and lightweight "t-tape". I adjust pressure to compensate for varying field sizes, elevations etc., by adjusting pump speed. It works well and any problems I have are usually due to my own management. < 11) How did you find out about our mailing list? >From an interesting web site focusing on sustainable agriculture. http://www.vtt.co.jp/staff/ancha/links/html< <---------------------------------------------------------------------------->
----------------------------------------- >From L.G. Smith 1) Briefly, what is your affiliation with trickle/drip irrigation? > I have had an active interest in drip for the last 13 yrs, I was a conservationist with the SCS until April of 94. Took the early out.< 2) What crops or plants do you use drip irrigation on? >I have worked with ssdi on fieldcorn and sdi on garden vegetables.< 3) Have you experienced a reduction in water use? >On the corn the avg. is 14-16"< 4) What problems have you encountered with drip irrigation? > Over watering, and trying to convince prospective users of the viability of the economics involved.< 5) What is the source of fertilizer used? >On the corn 32% UAN injected, no problems.< 6) Have you experienced a reduction in fertilizer and/or water use? >Yes! a reduction of 50% over the replaced surge system.< 7) Do you have water quality problems? If so, how do you tackle the situation? > None < 8) How frequent do you irrigate? Many times a day or just one long session per day or several days? >Just one long time, when the soil water deficit requires.< 9) Do you have rodent damage? If so, how do you control the problem? >Yes, but only in one field. The problem occurred shortly after installation and prior to pressuring the system. The tape was ripped in last years furrow which was full of that environment pleasing to the field mouse. The weather was warm and the soil relatively dry (therefore ripping created clods). The weather turned vary cold, and the field mice took advantage of the tunnels provided via the installation. Lesson: spring installation pressure up and get soil wet asap. We feel this should reduce the leaks courtesy field mice to a minimum.< 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? >I was running a search on www for (agriculture irrigation employment). I have told some of my friends about TRICKLE-L, hope to see them here also.< Thanks for making this list available. It is just what I was looking for. <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Sun Jul 14 20:44 EDT 1996
Date: Sun, 14 Jul 1996 19:32:43 -0500
Message-Id: .<.199607150032.AA16755@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 542

Contents:
Re: Emitter question/MIF gallery/new members (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.)
Re: SDI question (Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>.)

<---------------------------------------------------------------------->

Date: Sun, 14 Jul 1996 13:39:14 -0500 (EST) From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>. Subject: Re: Emitter question/MIF gallery/new members Richard, Most tape manufacturers recommend installing drip irrigation emitters facing upward. Don Pitts At 07:31 PM 7/13/96 -0500, you wrote: >I recently met some Australian visitors at our laboratory. One gentlemen >was a farmer who had recently purchased an SDI system for 50 acres (20 >hectares). I believe it was all tape and not hardhose. He was concerned >about the orientation of the emitter. The main focus of his concern was >that he thought the emitters had a greater chance of getting clogged if the >emitter was faced downward vs. facing up. I first told him that I had never >heard that question, and just off the top of my head said that I thought it >probably doesn't matter providing there is sufficient filtration upstream. >Then, thinking I had just put my foot in my mouth, I mentioned that I >honestly don't know the exact answer and would post the question to all >Trickle-L experts out there in cyberspace. So gang, does it matter how the >emitter is facing: up or down? > >Also, I don't think I have formally announced a new section on the >Microirrigation Forum web site (http://www.cybergate.com/~rmead) yet. I >have named it the Microirrigation Forum Digital Gallery. Please be sure to >check it out if you haven't already. There is a small database of images >related to drip/microspray issues, but I would like more input from people >as to what they would like to see and/or displayed. > >Finally, I wanted to update everyone about 2 new subscribers. Below are >responses from new Trickle-L members Jim Wright and L.G. Smith. > >Welcome Jim and L.G. !! > >Richard Mead >Trickle-L owner/manager >---------------------------------------------------------------------------- >----------------------------------------- >---------------------------------------------------------------------------- >----------------------------------------- >>From Jim Wright > >1) Briefly, what is your affiliation with trickle/drip irrigation? > >> I am a small grain farmer with up to a couple of acres of U-pick >>strawberries.< > >2) What crops or plants do you use drip irrigation on? > >>Strawberries, as well as a few market garden vegetables.< > >4) What problems have you encountered with drip irrigation? > >> Because I use surface irrigation, the tapes interfere with weeding. < > >6) Have you experienced a reduction in fertilizer and/or water use? > >>I couldn't grow strawberries without drip irrigation, since I don't have a >water source that would support sprinkler irrigation. < > >7) Do you have water quality problems? If so, how do you tackle the >situation? > >Water quality is adequate, but low lying soils would quickly >develop a salinity problem if large quantities of water were used. The >water is surface runoff collected in a dugout and subject to a series of >algal blooms each season. I use only a fine mesh screen filter and haven't >experienced serious problems with clogging. > >8) How frequent do you irrigate? Many times a day or just one long session >per day or several days? >>Several hours at a time as required.< > >9) Do you have rodent damage? If so, how do you control the problem? > >>Rodent damage minimal but coyotes scavenging overripe berries have done >>lots of >damage. I *have* had considerable rodent damage in storage, as I lift most of >the drip line each fall.< > >10) Are you pleased with the uniformity of your system or systems? Were they >designed correctly? > >>It is a very simple system, using a centrigual pump, >screen filters, and lightweight "t-tape". I adjust pressure to compensate >for varying field sizes, elevations etc., by adjusting pump speed. It works >well and any problems I have are usually due to my own management. < > >11) How did you find out about our mailing list? > >>From an interesting web site focusing on sustainable agriculture. >http://www.vtt.co.jp/staff/ancha/links/html< > >---------------------------------------------------------------------------- >----------------------------------------- >>From L.G. Smith > >1) Briefly, what is your affiliation with trickle/drip irrigation? > >> I have had an active interest in drip for the last 13 yrs, I was a >conservationist with the SCS until April of 94. Took the early out.< > >2) What crops or plants do you use drip irrigation on? > >>I have worked with ssdi on fieldcorn and sdi on garden vegetables.< > >3) Have you experienced a reduction in water use? > >>On the corn the avg. is 14-16"< > >4) What problems have you encountered with drip irrigation? > >> Over watering, and trying to convince prospective users of the viability >of the economics involved.< > >5) What is the source of fertilizer used? > >>On the corn 32% UAN injected, no problems.< > >6) Have you experienced a reduction in fertilizer and/or water use? > >>Yes! a reduction of 50% over the replaced surge system.< > >7) Do you have water quality problems? If so, how do you tackle the >situation? > >> None < > >8) How frequent do you irrigate? Many times a day or just one long session >per day or several days? > >>Just one long time, when the soil water deficit requires.< > >9) Do you have rodent damage? If so, how do you control the problem? > > >Yes, but only in one field. The problem occurred shortly after >installation and prior to pressuring the system. The tape was ripped in >last years furrow which was full of that environment pleasing to the field >mouse. The weather was warm and the soil relatively dry (therefore ripping >created clods). The weather turned vary cold, and the field mice took >advantage of the tunnels provided via the installation. Lesson: spring >installation pressure up and get soil wet asap. We feel this should reduce >the leaks courtesy field mice to a minimum.< > >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? > >>I was running a search on www for (agriculture irrigation employment). >I have told some of my friends about TRICKLE-L, hope to see them here also.< > >Thanks for making this list available. It is just what I was looking for. > > > <------------------------------>
Date: Sun, 14 Jul 1996 14:02:27 -0500 (EST) From: Don Pitts .<.djp@ICON.IMOK.UFL.EDU.>. Subject: Re: SDI question In most areas of the U.S. in which micro irrigation is widely practiced, water conservation is only one factor that has lead to grower adoption of the technology. The other factors that are usually present are: 1) improved horticultural or agronomic production as a result of chemigation, 2) reduced pest pressure and improved product quality, and 3) often higher yields. Economic factor will determine whether the technology is utilized. In most areas of the country, water is priced low compared to other production inputs. Therefore, in most cases, water conservation alone will not justify conversion to micro irrigation (or SDI). Don Pitts At 07:21 PM 7/5/96 -0500, you wrote: >Basant Maheshwari is one of the original subscribers to Trickle-L. He is touring >the US and is having trouble logging onto Trickle-L. He has asked me to >forward this >comment/question to group. > >R. Mead >Trickle-L owner/manager > >+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ > >Recently I visited a farm near Altus (Oklahoma State, USA) with subsurface >drip irrigation. I thought I will share my this experience of this visit >with the members on the list. > >The farmer is growing cotton and the total area under SDI is about 700 >acres. Water for SDI is drawn from a nearby canal and is cleaned through >three fine sand filters and treated with alum to avoid any clogging problem. >The whole system is computerised for the amount and timing of irrigation. >There is also some arrangement for injection of fertiliser into the water. >The system is in the first year of its operation. > >During the disucssion, the farmer mentioned that SDI has been very >beneficial to him in reducing the labor requirement and getting uniform >germination of seeds. The amount of water used so far has also reduced >considerably, but he thinks that water savings through SDI will be one of >his last consideations in adopting SDI for his farm (This is inspite of water >being relatively scarce in this area of Oklahoma). Other farmers in the >area are keenly watching the adventure of this farmer and may be one day >some of them will also follow him. > >Is water saving important and justifable factor for selecting SDI in a given >area? What do other people think on this question? > >Basant Maheshwari > > > > <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Tue Jul 16 19:37 EDT 1996
Date: Tue, 16 Jul 1996 18:23:33 -0500
Message-Id: .<.199607162323.AA18719@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 543

Contents:
Re: Emitter question/MIF gallery/new members (GroAire@aol.com)
 (flowers@rt66.com (wilderness flowers))
Re: TRICKLE-L digest 541 (danyalk@ix.netcom.com (Danyal Kasapligil))
Re: Emitter question/MIF gallery/new members (Rod Ennor .<.rodennor@parker.inter.net.il.>.)
Irrigation Technology Fieldday at Colby, KS Aug 20 (FLamm@oznet.ksu.edu (Freddie Lamm))

<---------------------------------------------------------------------->

Date: Sun, 14 Jul 1996 22:00:55 -0400 From: GroAire@aol.com Subject: Re: Emitter question/MIF gallery/new members The orientation of the emitters in SDI or surface systems should be placed as to allow any contaminants to settle to the bottom of the tape away from the emitter which should therefore be oriented on top. When the flow ceases, any silts that have gotten past the filtration systems will settle to the bottom. If the emitters are on the bottom then you run the risk of cementation or other related problems. GroAire Dave Enyeart <------------------------------>
Date: Mon, 15 Jul 1996 09:06:03 -0600 (MDT) From: flowers@rt66.com (wilderness flowers) Subject: unsubscribe <------------------------------>
Date: Mon, 15 Jul 1996 22:26:52 -0700 From: danyalk@ix.netcom.com (Danyal Kasapligil) Subject: Re: TRICKLE-L digest 541 You wrote: > >Trickle-L experts out there in cyberspace. So gang, does it matter how the emitter is facing: up or down? > YES UP is generally recommended because any fine particulates that pass through the filter ie very fine sands, silts & clays (or larger particles that enter through hose breaks etc) and settle out in the tape can accumulate & "bridge" (form aggregrates ie bound w/ organic matter - bacteria, algae) and plug the emitter inlet if the inlet is facing down. The idea is that w/ the emitter facing UP this material will settle on the bottom of the hose and be routinely flushed out of the system. The emitter facing up may also help direct the movement of water in the soil towards the surface (desirable w/ shallow rooted vegetables). <------------------------------>
Date: Tue, 16 Jul 1996 21:59:20 +0400 From: Rod Ennor .<.rodennor@parker.inter.net.il.>. Subject: Re: Emitter question/MIF gallery/new members At 07:31 PM 7/13/96 -0500, you wrote: >I recently met some Australian visitors at our laboratory. One gentlemen >was a farmer who had recently purchased an SDI system for 50 acres (20 >hectares). I believe it was all tape and not hardhose. He was concerned >about the orientation of the emitter. The main focus of his concern was >that he thought the emitters had a greater chance of getting clogged if the >emitter was faced downward vs. facing up. I first told him that I had never >heard that question, and just off the top of my head said that I thought it >probably doesn't matter providing there is sufficient filtration upstream. >Then, thinking I had just put my foot in my mouth, I mentioned that I >honestly don't know the exact answer and would post the question to all >Trickle-L experts out there in cyberspace. So gang, does it matter how the >emitter is facing: up or down? > I have no research data to back this up but I would think that if the "hardhose" is burried in the soil with the emitter hole in the top surface of the pipe, then the chances of soil particles entering through the hole when the system is de-pressurized would be greater than if the hole was in the underside of the pipe. If only because of gravity! As for clogging via sediment which has passed through the filters. DO NOT LET THE SEDIMENT GET INTO THE SYSTEM. I have seen first hand the effects of trying to save a few dollars by buying a filter system that was not effective, but it was cheaper. By spending another 20% on the price of the filter system we could have saved many hours of work and grown a higher yielding crop. I am sure that I have read on a brochure from one of the suppliers that their hardhose emitters work in all positions as the emitter takes the water from the center of the pipe as opposed to tape which takes it from the side. Has anyone else seen this? Rod Ennor <------------------------------>
Date: 16 Jul 96 13:33:43 CDT From: FLamm@oznet.ksu.edu (Freddie Lamm) Subject: Irrigation Technology Fieldday at Colby, KS Aug 20 Trickle-L members: I know there are a few in the Great Plains region (USA) that are interested in using SDI for field crops such as corn. I am scheduling a irrigation technology fieldday at Colby, KS for August 20, 1996. The afternoon session will be geared towards the general public. The fieldday is not intended to cover irrigated crop production, but is intended to cover the technologies we are investigating, in-canopy center pivot sprinkler irrigation and fertigation, and subsurface drip irrigation (SDI). If you are interested in attending and would like further details as August 20th approaches, please email or fax that you want to be on a mailing list for this event. 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 ************************


From root@crcnis1.unl.edu Wed Jul 17 19:35 EDT 1996
Date: Wed, 17 Jul 1996 18:23:35 -0500
Message-Id: .<.199607172323.AA03609@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 544

Contents:
Ooops, forgot new member (rmead@cybergate.com (Richard Mead))
Re: Emitter question/MIF gallery/new members (Wally Menke .<.wallym@ozemail.com.au.>.)
Re: Emitter question/MIF gallery/new members (Grsmiths@aol.com)
COLLOIDS/SETTLING AGENTS ("KEVIN B. BRONSON" .<.103644.2426@CompuServe.COM.>.)
Emitter direction (storlie@AESOP.RUTGERS.EDU)

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Date: Wed, 17 Jul 1996 04:14:07 GMT From: rmead@cybergate.com (Richard Mead) Subject: Ooops, forgot new member I recently posted responses from 2 new subscribers....I suddenly realized I neglected someone...my apologies to Gregory Miller. Also, I mistated my question 3 from the last posting. Instead of "3) Have you experienced a reduction in water use?" ...it should have read .."what is the average depth of placement of the drip lateral". R. Mead Trickle-L owner/manager <---------------------------------------------------------------------------->
>From Gregory Miller 1) Briefly, what is your affiliation with trickle/drip irrigation? >I am a homeowner with an interest in maintaining a hobby orchard. I have very limited prior use of trickle irrigation (home garden and landscaping) but am interested in using water conserving techniques, especially if they can be combined with concommitant chemical administration (fertilizers, etc.)< 2) What crops or plants do you use drip irrigation on? >Fruit trees (eventual total 50-60), cane fruit (approx 200 ft), blueberries (200 ft), bush fruit (20) and a vegetable garden. I will also incorporate it with (decorative) landscape irrigation, although I am currently planning to use sprinklers for grass irrigation (total area about 1000 sq ft)< 3) If using subsurface drip irrigation, what is the average depth of placement of the drip lateral? >I am interested in learning about different types of irrigation. Any pointers on good starting points would be appreciated.< 4) What problems have you encountered with drip irrigation? >clogged emitters (installer didn't use filter) and uneven coverage (too long a run with non PC emitters)< 5) Fertigation is a real advantage of drip irrigation. What form of N, P and K have you been trying and to what success? >Again, I'm willing to learn. From what I've seen, the material cost is higher, but I assume that labor savings offset this disadvantage.< 6) Have you experienced a reduction in fertilizer and/or water use? >Not applicable on fertilization. Neighbors within 2 miles have experienced decreased well output with drought and development. Although our ground water is plentiful, I see no need to waste it. I am concerned that to some extent I may be mining the ground water, rather than just utilizing annual accumulation.< 7) Do you have water quality problems? If so, how do you tackle the situation? >I use the same well that we use for domestic water supply. There is no problem with quality at the source, but I'm concerned about algae, etc. with an above ground system.< 8) How frequent do you irrigate? Many times a day or just one long session per day or several days? >No current experience, but it is preferable with my setup to have my pump run continuously (to avoid excessive wear from on/off cycling) but am concerned about trying to allocate 20 gal per min. I have worked out that I can do this with 2 gal per hr emitters (including garden irrigation) which should work well with my sandy soil, but am concerned about whether this is the best way to administer water. I plan to administer water utilizing evapotranspiration calculations to at least some extent.< 9) Do you have rodent damage? If so, how do you control the problem? >pocket gophers in the area. If close to critical areas, propane down the hole. Coyotes exert some control, too.< 10) Are you pleased with the uniformity of your system or systems? Were they designed correctly? >Not applicable. I expect that my system will need some tuning in the future. I just want minimize those changes.< 11) How did you find out about our mailing list? >WWW search on drip irrigation, in anticipation of setting up a system.< <------------------------------>
Date: Wed, 17 Jul 1996 22:47:50 +1000 (EST) From: Wally Menke .<.wallym@ozemail.com.au.>. Subject: Re: Emitter question/MIF gallery/new members At 07:30 PM 13/07/96 -0500, you wrote: >I recently met some Australian visitors at our laboratory. One gentlemen >was a farmer who had recently purchased an SDI system for 50 acres (20 >hectares). I believe it was all tape and not hardhose. He was concerned >about the orientation of the emitter. The main focus of his concern was >that he thought the emitters had a greater chance of getting clogged if the >emitter was faced downward vs. facing up. Dear Richard & Others I know there is a group of growers over there from central Victoria on a visit to CalPoly for a course, (and no doubt some serious partying). Nearly all these growers would be using soft wall tape of about 12 mil wall thickness, with the emitter stuck to the inner wall of the tube, and only one outlet per emitter. They can generally get 2-3 years service if there carefull, some use it one year only. >From what I've seen in the field (I need to double check) its usually buried 5-8 cm (2-3") underground with the emitter face up. To my knowledge blockage by dirt ingestion does'nt appear to be a problem, especially when air valves are fitted at the high points. No doubt hardwall tube (like Drip-In or Naan) that has a few outlets per emitter would be less prone to external blockage. Filtration varies, but generally is fully automatic screen, disc or media. All of which work quite well, although the automatic screen filters are the simplest.(my bias showing). Pumps are usually diesel powered. These systems are usually made to move around as different land becomes available to rent or lease from season to season. Root intrusion is avoided by pouring Treflan/trifluralin down the system, which is a no-no here, as it is not approved for this application. But some dripline companies are still recommending this method. Regards Wally Menke Triangle Filtration - Australia <------------------------------>
Date: Wed, 17 Jul 1996 10:44:59 -0400 From: Grsmiths@aol.com Subject: Re: Emitter question/MIF gallery/new members Richard, We are cancelling AOL and changing our address to greensmiths@intur.net. Can you please change our address. I really enjoy your group and don't want to loose the subjects. <------------------------------>
Date: 17 Jul 96 11:52:24 EDT From: "KEVIN B. BRONSON" .<.103644.2426@CompuServe.COM.>. Subject: COLLOIDS/SETTLING AGENTS DEAR LIST MEMBERS: This question is not directly related to low volume irrigation, but I am offering it to see if anyone has experience they will share. My customer is growing tomatoes in heavy clay soil, and fresh packs them in his own plant. He has a ?4000 gallon wash tank/chlorine bath (for bacterial control) that loads with suspended clays very quickly (several hours) and binds the chlorine, forcing him to add more chlorine. Chlorine levels sometimes reach 350 PPM, and the cost of doing so is prohibitive. I obtained a 5 micron filter sock, and estimate after an informal jar test that only 5% - 10% of the particles are larger than 5 micron, so I don't believe that direct filteration is feasible. I am wondering if it would be possible/feasible to use a coagulating agent to bind the clay particles so they can be settled out in a tank of filtered. If so, what kind of settling time could be expected, or what parameters would be required of a filter? Are there other ways to control the bacteria that would not be affected by the sediment level, such as ozone or hydrogen peroxide that would be cost effective? Kevin Bronson Weimer Irrigation & Supply, Inc 6061N Winton Way Winton, CA 95388 Phone (209)358-1443 Fax (209)358-1444 EMail 103644,2426@Compuserve.com <------------------------------>
Date: Wed, 17 Jul 1996 14:48:34 -0400 (EDT) From: storlie@AESOP.RUTGERS.EDU Subject: Emitter direction Hi All: Emitter direction is a no brainer...from my first introduction years ago...to every written reference I've seen...to seeing twisted tape that clogged only where facing down...including clogged Typhoon that was installed with "no particular attention paid to emitter direction"...point 'em towards the sky and save yourself headaches...both surface and sdi... Craig Storlie Extension Specialist in Agricultural Engineering <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Thu Jul 18 19:35 EDT 1996
Date: Thu, 18 Jul 1996 18:23:59 -0500
Message-Id: .<.199607182323.AA25963@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 545

Contents:
Microjet=AE (VAN DEN EYNDE Pierre .<.vandeneynde@geru.ucl.ac.be.>.)
Re: COLLOIDS/SETTLING AGENTS ("J.D. Oster" .<.oster@mail.ucr.edu.>.)

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Date: Thu, 18 Jul 1996 11:01:10 +0200 From: VAN DEN EYNDE Pierre .<.vandeneynde@geru.ucl.ac.be.>. Subject: Microjet=AE On June the 5th, Eric Jooste wrote something about the MICROJET=AE technology for irrigating trees. The message was however signed by Vernon B Studti.. Since there was no Email address at the end of the message, I've got no other way to get in touch than through the list. Sorry for unconvenience for the others. I would be interested to know a bit more about this MICROJET=AE system. Thanks. Pierre VAN DEN EYNDE vandeneynde@geru.ucl.ac.be <------------------------------>
Date: Thu, 18 Jul 1996 13:18:06 -0500 From: "J.D. Oster" .<.oster@mail.ucr.edu.>. Subject: Re: COLLOIDS/SETTLING AGENTS Alum may work. At 10:53 AM 7/17/96 -0500, you wrote: >DEAR LIST MEMBERS: > >This question is not directly related to low volume irrigation, but I am >offering it to see if anyone has experience they will share. My customer is >growing tomatoes in heavy clay soil, and fresh packs them in his own plant. He >has a ?4000 gallon wash tank/chlorine bath (for bacterial control) that loads >with suspended clays very quickly (several hours) and binds the chlorine, >forcing him to add more chlorine. Chlorine levels sometimes reach 350 PPM, and >the cost of doing so is prohibitive. > >I obtained a 5 micron filter sock, and estimate after an informal jar test that >only 5% - 10% of the particles are larger than 5 micron, so I don't believe that >direct filteration is feasible. I am wondering if it would be possible/feasible >to use a coagulating agent to bind the clay particles so they can be settled out >in a tank of filtered. If so, what kind of settling time could be expected, or >what parameters would be required of a filter? > >Are there other ways to control the bacteria that would not be affected by the >sediment level, such as ozone or hydrogen peroxide that would be cost effective? > >Kevin Bronson >Weimer Irrigation & Supply, Inc >6061N Winton Way >Winton, CA 95388 >Phone (209)358-1443 >Fax (209)358-1444 >EMail 103644,2426@Compuserve.com > > 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 ************************


From root@crcnis1.unl.edu Fri Jul 19 19:36 EDT 1996
Date: Fri, 19 Jul 1996 18:24:07 -0500
Message-Id: .<.199607192324.AA18414@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 546

Contents:
Re: Irrigation Technology Fieldday at Colby, KS Aug 20 (ABMFRESNO@aol.com)

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Date: Fri, 19 Jul 1996 18:23:09 -0400 From: ABMFRESNO@aol.com Subject: Re: Irrigation Technology Fieldday at Colby, KS Aug 20 MY MAILING ADDRESS IS: JIM ANSHUTZ, P.E. ABM & ASSOCIATES, INC. 7175 N. DURANT AVE. FRESNO, CALIFORNIA 93711 ABM & ASSOCIATES, INC. HAS A SALES MANAGER LOCATED IN TEXAS SERVICING THE DRIP/MICRO MARKET THERE. THANK YOU <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Mon Jul 22 01:09 EDT 1996
Date: Sun, 21 Jul 1996 23:52:44 -0500
Message-Id: .<.199607220452.AA04475@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 547

Contents:
Re: COLLOIDS/SETTLING AGENTS (HOPSRME@aol.com)

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Date: Mon, 22 Jul 1996 00:53:57 -0400 From: HOPSRME@aol.com Subject: Re: COLLOIDS/SETTLING AGENTS I am not very familiar with growing tomatoes, or packing them for that matter, but we use a product in our rill irrigated fields called PAM. It is an acronym for PolyAcriMide. It is a white powder that binds with soil particles and "drops" them out of solution. We use it for erosion control in our furrows. It is 100% effective. It is very, very safe. I have heard that some cities use it to clean their drinking water supplies with. In the arid area of Central Washington State, were I am from, there are thousands of acres of irrigated land that PAM is being used on. Hope this helps. Eric <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Tue Jul 23 08:15 EDT 1996
Date: Tue, 23 Jul 1996 07:04:32 -0500
Message-Id: .<.199607231204.AA26682@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 548

Contents:
trickle: Thanks for help (Jochen.Eberhard@t-online.de (Jochen Eberhard))

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Date: Tue, 23 Jul 96 12:23 +0100 From: Jochen.Eberhard@t-online.de (Jochen Eberhard) Subject: trickle: Thanks for help Hi, thanks a lot for all the help some of you gave me with my tensiometers. So I could eliminate the technique as the guilty part. As it now seems to me, I am the one to blame, because it is just the lack of water. :-)) I doppled the application rate and.. surprise :-) surprise.. the tensiometer readings start coming down, very slow but that is the way I like it. As I often say to my colleques, the technique usually works well, most of the problems are caused by the people working with it (wrong interpetation, wrong application rates, wrong irrigation scheduling, ect.) While thinking about my own problems another question came up in my mind. With high transpiration rates the soil moisture is not the same as with low transpiration rates although the tensiometers show the same soil moisture tension. Is this correct? And if so, is it possible to messure the plant directly in a simple way to see at with tensiometer reading the plant starts to react on the decreasing water supply (closing the stomata...). I know the leaf temperature method. This is just some kind of brainstorming I am doing, not a high quality scientific thinking. Any comments are welcome. Jochen Eberhard, Germany email: Jochen.Eberhard@t-online.de <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Wed Jul 24 08:21 EDT 1996
Date: Wed, 24 Jul 1996 07:09:09 -0500
Message-Id: .<.199607241209.AA16104@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 549

Contents:
Re: trickle: Thanks for help (FLamm@oznet.ksu.edu (Freddie Lamm))
RE: trickle: Thanks for help (Jody Worthington .<.jworth@our-town.com.>.)

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Date: 23 Jul 96 09:06:24 CDT From: FLamm@oznet.ksu.edu (Freddie Lamm) Subject: Re: trickle: Thanks for help > And if so, is it possible to messure the plant directly in a simple way to see > at with tensiometer reading the plant starts to react on the decreasing water > supply (closing the stomata...). I know the leaf temperature method. > This is just some kind of brainstorming I am doing, not a high quality > scientific thinking. > Any comments are welcome. > > Jochen Eberhard, Germany > email: Jochen.Eberhard@t-online.de > Are you familiar with measurements of leaf water potential or xylem pressure measurements with a leaf pressure bomb. 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: Tue, 23 Jul 1996 16:41:11 -0500 From: Jody Worthington .<.jworth@our-town.com.>. Subject: RE: trickle: Thanks for help ------ =_NextPart_000_01BB78B6.04A31C00 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable I did not get in on the first of the question somehow, so I may be = answering a question out of context. Several years ago we did some work in peanuts comparing the rate of = photosynthesis and crop water stress index using IR thermometer to = tensiometer values of soil moisture. The plant response actually = depends upon the evaporative demand. On hot dry, windy days, a modest = negative increase in soil moisture tension (20-30 cb) compared to -15cb = resulted in a sizable change in the rate of CO2 fixation and increase in = crop water stress index. In humid conditions, the crop water stress = index is not too reliable, but there was very little depression in = photosynthetic rate between plants growing at -15cb and -30 cb under = these low demand conditions. Jody Worthington ------ =_NextPart_000_01BB78B6.04A31C00 Content-Type: application/ms-tnef Content-Transfer-Encoding: base64 eJ8+IgQVAQaQCAAEAAAAAAABAAEAAQeQBgAIAAAA5AQAAAAAAADoAAENgAQAAgAAAAIAAgABBJAG ABABAAABAAAADAAAAAMAADADAAAACwAPDgAAAAACAf8PAQAAAEEAAAAAAAAAgSsfpL6jEBmdbgDd AQ9UAgAAAAB0cmlja2xlLWxAdW5sLmVkdQBTTVRQAHRyaWNrbGUtbEB1bmwuZWR1AAAAAB4AAjAB AAAABQAAAFNNVFAAAAAAHgADMAEAAAASAAAAdHJpY2tsZS1sQHVubC5lZHUAAAADABUMAQAAAAMA /g8GAAAAHgABMAEAAAAUAAAAJ3RyaWNrbGUtbEB1bmwuZWR1JwACAQswAQAAABcAAABTTVRQOlRS SUNLTEUtTEBVTkwuRURVAAADAAA5AAAAAAsAQDoBAAAAAgH2DwEAAAAEAAAAAAAAA6QuAQiABwAY AAAASVBNLk1pY3Jvc29mdCBNYWlsLk5vdGUAMQgBBIABAB0AAABSRTogdHJpY2tsZTogVGhhbmtz IGZvciBoZWxwANIJAQWAAwAOAAAAzAcHABcAEAApAAsAAgA3AQEggAMADgAAAMwHBwAXABAAHQAs AAIATAEBCYABACEAAABDRkE1Mzc4M0E2RTRDRjExQUZBMjQ0NDU1MzU0MDAwMAALBwEDkAYAOAQA ABIAAAALACMAAAAAAAMAJgAAAAAACwApAAEAAAADADYAAAAAAEAAOQDAwiGq33i7AR4AcAABAAAA HQAAAFJFOiB0cmlja2xlOiBUaGFua3MgZm9yIGhlbHAAAAAAAgFxAAEAAAAWAAAAAbt436ohgzel 0OSmEc+vokRFU1QAAAAAHgAeDAEAAAAFAAAAU01UUAAAAAAeAB8MAQAAABQAAABqd29ydGhAb3Vy LXRvd24uY29tAAMABhDxJGVMAwAHEHkCAAAeAAgQAQAAAGUAAABJRElETk9UR0VUSU5PTlRIRUZJ UlNUT0ZUSEVRVUVTVElPTlNPTUVIT1csU09JTUFZQkVBTlNXRVJJTkdBUVVFU1RJT05PVVRPRkNP TlRFWFRTRVZFUkFMWUVBUlNBR09XRURJAAAAAAIBCRABAAAAtgIAALICAAD6AwAATFpGdXFmOAj/ AAoBDwIVAqgF6wKDAFAC8gkCAGNoCsBzZXQyNwYABsMCgzIDxQIAcHJCcRHic3RlbQKDM/cC5AcT AoB9CoAIzwnZAoAHCoENsQtgbmcxMDMPFFALChRRC/EgSSBkoGlkIG5vBUBnEcAKIAuAIAIgIHRo ZZggZmkRoAVAb2Yak1ZxClATwGkacXMDcGVwaG93LBwxGVEAwHnsIGIawABxdwZxF8AdgB8bqAhg GyMFoAIwZXh0bi4KhgGRBlF2BJAHQCDseWURkR2AZxzgHcAZc1ccQiGgBbBrGjJwISBu9x7wBCAF oG0KsR3yGqIg0AsT0BsycByAdG9zeW8CMBqwAJAhUW4ZoAUAb/5wIaAkYQXAE8AWEAQRC4AxDbB4 IHUAkB4BSVL9GpJyBGAHgCZyJQAakAnw+wCQKGV2B0AbwRsyHEADEQsEYAQAdAhwZS4gIL5UGrEL UQIwJEAHkHACINsRsB2AYyrwB0BsHUANsHci8CXQBCB1LDEakyCgYbssMCRRaSCwLREDgWQrMc5P A6Ak4RlwcnkcsAPw9yXQLQEdMHMcsB4wBGIbEfhuZWculAuABQAhICxhLxpBKmso9QOgKAHQLTNx GUBjYikjZQmAKMItzDE1NLAr8nVsE9AZoNcaQR4wAJB6AaBsGsARcWcXwDKTJBpDTxHgGuB4fy6R GnElwjIqJg8nFCsxSfkvkXVtGZEfURmAG/Iw0f8aojqvJxUlkRnCJQAc4BYQ7mwHMDcxHLBiHvEo EiJR/zJwKbAEkB1AQCACQDdBLSHfJtIcAiLCJOgb8GMkRB1g/nQdwAnwK5QEIAnAHJAd8/8FQDW0 JcI0dCdwJzEosSVhfxrAFaAH4C70PMkfy0mtSmsEcB1AVxWxaB3xJQBuCwqFFTEATJAAAAMAEBAA AAAAAwAREAAAAABAAAcwYOzFEN54uwFAAAgwYOzFEN54uwEeAD0AAQAAAAUAAABSRTogAAAAAIkv ------ =_NextPart_000_01BB78B6.04A31C00-- <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Thu Jul 25 08:21 EDT 1996
Date: Thu, 25 Jul 1996 07:10:15 -0500
Message-Id: .<.199607251210.AA21988@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 550

Contents:
UNSUBSCRIBE ("J. L. Jones" .<.jljones@earthlink.net.>.)

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Date: Thu, 25 Jul 1996 04:47:27 -0700 From: "J. L. Jones" .<.jljones@earthlink.net.>. Subject: UNSUBSCRIBE UNSUBSCRIBE <------------------------------>
End of Digest ************************


From root@crcnis1.unl.edu Mon Jul 29 08:45 EDT 1996
Date: Mon, 29 Jul 1996 07:32:18 -0500
Message-Id: .<.199607291232.AA11611@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 551

Contents:
Sand Tube Irrigation, STI (Masoud Meshkat .<.mmeshkat@groucho.bae.uky.edu.>.)

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Date: Sun, 28 Jul 1996 14:35:37 -0400 (EDT) From: Masoud Meshkat .<.mmeshkat@groucho.bae.uky.edu.>. Subject: Sand Tube Irrigation, STI Dear Friends of Trickle-l Recently I presented a paper " no. 962103" at the ASAE meeting in Phoenix on the "EVALUATION OF THE "SAND TUBE IRRIGATION, STI" METHOD TO INCREASE THE EFFICIENCY OF SURFACE DRIP IRRIGATION IN ARID LAND FARMING". I believe several members of Trickle-l were present at the presentation. Since the subject emphasizes drip irrigation efficiency, I thought it would be a good idea to share it here, to hear the comments and thoughts and expertise of this group that I have learned so much from in the past year. Although the idea is simple and may be practiced on some farms for different purposes, I could not find any particular researched literature about it. May be the members of this forum can direct me to some references. Water conveyance efficiency of a microirrigation system undoubtedly surpasses that of flood and furrow irrigation. Yet, under certain circumstances water usage efficiency of surface drip irrigation may have room for enhancement. Due to inherent characteristics of drip irrigation, its lower frequency (day or hours) of water application often leaves a wet surface or a water puddle beneath each emitter. In areas of high evaporative demand, such as Midwest United States, hot and dry climates, and particularly on soils with low infiltration capacity considerable evaporation from the soil surface may occur. Although shading reduces the amount of radiation received by the evaporating surface thus lowering the evaporation potential, It is evident that due to the higher rate of solar radiation received by the drier soil surrounding the wetted region beneath an emitter, a greater differential of vapor pressure exists between these two regions. The considerable drying power of dry and hot air moving across the parched land, blown over the moist soil beneath emitter, may hamper the effect of shading. To increase the efficiency of surface applied drip irrigation, it is suggested that a column of soil be extracted beneath the emitter point and filled with coarse sand, thus eliminating the water puddle and moisture at the surface. The specifics of the STI method applies, in particular, to the permanent tree crops, where achieving higher water usage is a never ending challenge. The STI method affects evaporation process during the three stages of the evaporation. These stages are: initial constant-rate stage, intermediate falling-rate stage and residual slow-rate stage. STI reduces evaporation to the residual slow-rate stage by encompassing the three basic principles of evaporation reduction: (1) controlling energy to the site of evaporation by distancing the actual water surface from the ground surface, (2) reducing the potential moisture gradient by maintaining a drier surface there by warming the soil and producing a downward-acting thermal gradient that forces the moisture to migrate from the hotter surface zone to cooler depths below, and (3) decreasing conductivity of soil because water is not applied at the surface and soil crusting does not occur and the surface is maintained in a dispersed state. Subsurface drip irrigation (SDI) has reduced the soil evaporation inefficiency in most cases where no chimney effect (resurfacing of water to the soil surface along the trench buried irrigation tubing) is present. However, for the most part conversion of currently existing surface drip irrigation to SDI is taking place with caution by producers or is totally unfeasible because of the capital requirement or the farmer is satisfied with his current existing system. The STI method presented here is to enhance the efficiency of surface drip irrigation, particularly in areas where the climatic condition, soil characteristic and crop irrigated are such that inefficiency of water usage due to soil evaporation is considerable. Look forward to hear your comments. Masoud Meshkat 128 Agricultural Engineering Building University of Kentucky Lexington Ky, 40546-0276 E-mail: mmeshkat@bae.uky.edu Fax: (606)257-5671 Tel: (606)257-3000 Ext. (280) <------------------------------>
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From root@crcnis1.unl.edu Tue Jul 30 08:44 EDT 1996
Date: Tue, 30 Jul 1996 07:32:51 -0500
Message-Id: .<.199607301232.AA29764@crcnis1.unl.edu.>.
From: trickle-l@unl.edu
Subject: TRICKLE-L digest 552

Contents:
Job Wanted (storlie@AESOP.RUTGERS.EDU)
Re: Ionized water and SDI on vines (geoflow1@slip.net (Rodney Ruskin))
Re: Ionized water and SDI on vines (LodiCraig@aol.com)

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Date: Mon, 29 Jul 1996 11:56:19 -0400 (EDT) From: storlie@AESOP.RUTGERS.EDU Subject: Job Wanted IRRIGATION ENGINEER SEEKS EMPLOYMENT Available Immediately - Relocation Desired Agricultural Engineer with 6 years of University Extension experience at Rutgers University seeks employment with educational institution, government agency, or commercial agricultural company in education, research, product development, or management position. I am an expert in drip irrigation and related plasticulture and vegetable production techniques (mulches, row covers, tunnels, and greenhouse production systems). Agricultural Engineering degrees include B.S. (1983) and M.S. (1985) from the University of Wisconsin-Madison and Ph.D. from the University of Nebraska-Lincoln (1990). Other skills include electronics and instrumentation expertise, personal computer software and hardware applications experience, an understanding of vegetable production techniques and horticulture, and extensive experience in field- base,d applied irrigation research. I am valued and respected as an educator and team player by the faculty I work alongside of and by the clientele I serve. I desire to continue in a position as a team player, and to excel as an individual and a leader. Personal skills, including communication skills, are excellent. Dr. Craig Storlie Extension Specialist in Agricultural Engineering Rutgers Research and Development Center 121 Northville Road Bridgeton, NJ 08302 (609)455-3100 <------------------------------>
Date: Mon, 29 Jul 1996 11:56:07 -0700 From: geoflow1@slip.net (Rodney Ruskin) Subject: Re: Ionized water and SDI on vines Trickle-l has been quiet for quite a while. Is everyone away for the summer? I hope that this topic will stir up some discussion. Ionization of water and vigor in grape vines: Jim Murphy of Murphy-Goode Vineyards in Sonoma County advised me that he has achieved surprisingly good results in a test of ionized water for SDI irrigation of grape vines which are suffering from phylloxera. He said that the vines showed a considerable increase in vigor and a meaningful reduction in the effects of the phylloxera. Everything that I have previously heard about ionized water is that it does not show any value in scientific replicated trials. Jim Murphy is a very serious grower and is the pioneer of SDI in grape vines. I must give strong credibility to his experience. Does anyone out there have any good scientific information about ionized water for irrigation? Does anyone out there have any good scientific information as to how it may be of benefit, as found by Jim? Is anyone out there interested in doing a study of ionized water with SDI on grape vines with and without phylloxera? Rodney Ruskin geoflow1@slip.net <------------------------------>
Date: Mon, 29 Jul 1996 23:49:41 -0400 From: LodiCraig@aol.com Subject: Re: Ionized water and SDI on vines This is interesting stuff to me. I would enjoy a couple of clarifications: In a message dated 96-07-29 15:01:12 EDT, you write: >Jim Murphy of Murphy-Goode Vineyards in Sonoma County advised me that he >has achieved surprisingly good results in a test of ionized water for SDI >irrigation of grape vines which are suffering from phylloxera. He said that >the vines showed a considerable increase in vigor and a meaningful >reduction in the effects of the phylloxera. 1. What is the method of ionization? Is it high intensity U.V. light treatment? 2. We have seen similiar results after installing S.D.I. and commencing fertigation, but no ionization. Does Mr. Murphy have one or multiple untreated control blocks? 3. Is this the first year of ionized water application? We had an unusually high vigor spring ... the timing of rains and spring temperatures made for very vigorous vineyards ... it took the rest of this summer and extensive leaf pulling to get the vines back into balance. Cheers, Craig Thompson <------------------------------>
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