Brief Summary of Minutes of Annual Meeting

Meeting Minutes W-1128 Annual Meeting November 17-19, 2004 Tampa, Florida The meeting was opened at 8:10 am by Clint Shock. Members (M) and guests (G) present included: Gary Clark (M, Secretary), Muluneh Yitayew (M), Larry Schwankl (M), Clint Shock (M, Chair), LeRoy Daugherty (Admin. Advisor), Craig Stanley (M, Vice Chair), Mick ONeill (M), Howard Neibling (M), Clair Prestwich (G), Freddie Lamm (M), Paul Colaizzi (M), Ali Fares (G), Bruce Lesiker (M), Alan Lasko (M), Rick Piccioni (G) Ken Shackel (M), Henry Taber (M), Bill Branch (M), Abdel Berrada (M), Peter Robinson (G), Mahbub Alam (M), Elvin Roman-Paoli (M), Dan Rogers (G), Andre Peirera (G), Prem Singh (M) [M=member; G=Guest] Members introduced themselves. Minutes from the 2004 meeting were discussed and approved. LeRoy Daugherty addressed the group and discussed the format for the annual report. This report will be the final report for the W-128 project. We just started the W-1128 project on Oct 1, 2004. The report needs to follow the App D SAES-422 format for multistate research activity. The impact (or potential impacts) section is very important. Each participant needs to work their own AES director to get their projects into the CRIS system. A copy of the memo from the USDA to each of the AES directors was passed out. A printed copy of the project proposal was handed out. The App E information (listing of members) is in that printed copy. The members list is a dynamic list and can change with time in the project. A screen print of the NIMSS website was handed out. Project participants can access as Guests. Information on this project and members can be located on that site. Other projects and project members can be viewed as well. Clint Shock discussed the annual report. Gary Clark suggested that the Secretary handle the annual report. The proposed duties are: Secretary - Meeting minutes and annual report; Vice-Chair - arrangements for the annual meeting; Chair - Conduct the annual meeting Larry Schwankl suggested that we discuss the duties of the officers during the business meeting. We also need to discuss the 2005 meeting location and elect a new secretary. State Progress Reports were conducted on Wednesday and Friday. Details are provided at the end of these minutes. Business Meeting: 1. Location and date for 2005 meeting. The 2005 IA meeting is Nov 6-8 in Phoenix; the 2005 ASA meeting is Nov 6-10 inSalt Lake City. The group planned to have the meeting in Phoenix November 2-4, 2005 (Muluneh Yitayew, local host). A motion made by Larry Parson, seconded by Larry Schwankl. Motion passed. 2. Motion to change the duties of the secretary to take the meeting minutes and to compile the annual report. Motion made by Freddie Lamm, seconded by Craig Stanley. Motion passed. Gary will email a shell format of the annual report to all members. Report needs to be completed by 60 days after the annual meeting. Gary would like the individual annual reports emailed to him by December 1 in the correct format. 3. Hank, Ken and Freddie will serve as a nominating committee for the proposed new secretary. Motion was made and passed. 4. Discussion on project participation. Many listed members do not come to the annual meetings, but are listed as project members. Active members pull the annual report together and develop the project proposals. However, many inactive members do not contribute, but are still listed as members. LeRoy D. explained how the regional project process works. Project participants can be added to the project by the individual state AES directors; their participation is not determined by the current/active project members. Following discussion focused on inactive members. Freddie made a motion that LeRoy bring a concern to the other AES directors that there are some concerns from this committee about inactive membership. Seconded by Ken S. Discussion followed with many viewpoints. While concerns exist, the impacts to the group are minimal. Motion wasa withdrawn. Presentations at the next meeting might be arranged around objectives, milestones and impacts. 5. Milestones for 2005. Group discussed milestones for 2005. Project participants were identified with each milestone and a milestone group leader. Larry & Craig suggested that the committee chair coordinate with each of the milestone subtopic groups. Each group needs to coordinate among themselves about what they will do over the next year. The meeting in 2005 should focus around project objectives and milestones. Thursday Tour (11/18/2004) 1. Small container ornamentals (Rick Brown). All drip irrigated using elevated collapsible emitting hose (drip tape) 2. Drip irrigated trees (oaks, citrus,&). County agent is doing a study of scheduling using tensiometers. 3. Microspray irrigated bamboo site visit. 4. New Gulf Coast Research and Education Center facilities 5. Dover Research Center  Strawberry research 6. Strawberry farm visit (Carl Grooms) Friday, 11/19/2004. Election of new secretary. Two nominations from the nominating committee. Ali Fares and Mick ONeill. No other nominations were provided. Mick ONeill was elected as the incoming secretary for 2005. The meeting was adjourned on Friday November 19, 2004 at 11:30 am. These minutes are respectfully submitted by: Gary Clark, Secretary, W1128 Kansas State University - Department of Biological and Agricultural Engineering gac@ksu.edu 785-532-2909 Summary of State Reports (11/17/2004): 1. Prem Singh  Univ. of Guam. Discussed a lysimeter facility and irrigation scheduling study for watermelon. The site was instrumented to measure soil water potential and leachate. Temperatures under the black plastic mulch reached 76 C during the day. These high temps killed the transplants. A soil salinity study was also discussed. Soil salinity was measured at different positions with respect to the drip lateral. 2. Elvin Roman-Paoli  Univ of Puerto Rico. Presented studies that address objective 3. Eval. Of soil moisture level on growth and productivity of young citrus and avocado. Trees were irrigated with microsprinklers and scheduled with tensiometers (10-15 cb, 30-35 cb, rainfed). 3. Ali Fares  Univ. of Hawaii-Manoa. Irrigation scheduling for optimum plant water and nutrient uptake. Presented information on the crops and production systems in Hawaii. Work focuses on irrig. scheduling for tomato with drip irrigation. Presented information on use of ECH20 probes and EasyAg probes. 4. Paul Colaizzi  USDA/ARS, Bushland, TX. Subsurface drip irrigation research in Texas. Subsurface drip irrigation (SDI) may be up to 5% in the panhandle of TX. Advantages of SDI in TX: Better crop response under deficit irrig. compared to LEPA and spray irrig.; increased WUE under deficit irrig.; good response with grain sorghum and cotton. SDI has resulted in improved earliness of maturity in cotton. Results were presented for cotton grown under dryland, MESA (mid elevation spray application), LESA (low elevation spray application), LEPA (low energy precision application), and SDI. Irrigation treatments were set at levels of 0.25, 0.50, 0.75, and 1.00 fractions of non-stressed crop ET (or full ET). SDI performed better than other treatments at levels of 0.25 and 0.50. 5. Henry Taber  Iowa State University, Ames, IA. Presented results on objectives 1 and 4. Drip irrigated bell peppers were scheduled using (1) tensiometers or Watermark sensors set at 25 - 30 kPa (25% depletion) and (2) crop water balance (ET-based). One pepper variety had a significantly greater yield (12% or 235 bu/ac) with treatment 2 as compared to treatment 1. 6. Mick ONeill  New Mexico State University, Farmington. Water supply is reservoir storage from the Navajo Dam. Levels were near full in 1999, 2000, 2001. Levels started to decline in 2002 and are currently very low. Subsurface drip irrigation for field crops. Purpose to evaluate SDI for field crops and to train NAPI technicians. Depth of drip tape influenced yield of corn. Also discussed subsurface drip for hybrid poplar. A nearby timber mill will use all of the hybrid poplar that can be produced. 7. Larry Parsons  University of Florida, Lake Alfred, FL. Presented information on water use of citrus. Water allocations are being reduced. Value of juice oranges is based on Brix (pounds solids) and juice content. Some studies have indicated that mild stress in the fall may increase the Brix value without reducing yield. Studies were designed to address this issue using Valencia orange on a Swingle citrumelo rootstock. 8. Larry Schwankl  University of California. Measurement of chemical precipitation in microirrigation systems  primarily iron. Can treat by precipitating in a pond or reservoir, or treating with phosphonic acid. Two sites are under study (2ppm iron and 18 ppm iron). Chemicals that are being studied: LineMaster, Microclean, Lineout, Sureflow, and Driprite 3000. 9. Ken Shackel  Univ. of California  Davis. Regulated deficit irrigation (RDI) during hull split in almonds. Benefits may include speed up hull split, reduce hull rot, reduce water use. Studies investigated timing and amount of midday stem water potential stress 10. Muluneh Yitayew  University of Arizona. Water and salinity management for corn in an arid environment. Evaluated seasonal irrigation requirements for field corn under drip and furrow irrigation. Developed a yield function for field corn and a crop coefficient curve based on heat units. A second presentation was provided on a salinity study. Water with different salinity levels was applied using SDI to corn plots. State Reports Continued (11/19/2004) 11. Alan Lasko  Cornell University. Measurement and modeling of water use by apple trees in NY. Measured water use rates for orchards using sap flow gauges. Found high variability among measured results from gauges placed on similar trees. Also used whole plant gas exchange to calibrate sap flow gauges  this improved results. Also measured climatic data in the orchard to assess boundary layer flow conditions. 12. Howard Neibling  University of Idaho. Drip irrigation and irrigation scheduling in Idaho. Studied use of drip irrigation for winter wheat production. Used Watermark sensors to measure soil water potential in the drip irrigated wheat plots. Also conducting studies on microsprinkler irrigation of sugar beets. 13. Gary Clark - Kansas State University, Manhattan. Hydraulic performance of drip irrigation tubing products with livestock lagoon wastewater. Hydraulic performance data for the past 2 years was presented. A lysimeter study on drip irrigation of Poplar trees with livestock lagoon wastewater was initiated in 2004. 14. Freddie Lamm - Kansas State University, Colby. Studies on simulated LEPA and SDI for corn in NW Kansas. Drip lines were positioned about 15-in. deep in alternate beds between plant rows. Presented 7 years of results. A SDI frequency of irrigation study was also presented. 15. Clint Shock  Oregon. Microirrigation of hybrid poplar. Did studies on: a comparison of microirrigation systems on poplar; poplar clone evaluations; bulking of potato clones under drip; drip tape and potato seed configuration; options for automation and frequency of drip on onions; timing of stress on drip irrigated onions; evaluation of Vydate through drip for control of thrips; demonstration of corn and alfalfa forage production, N-rate for drip irr. Onion and carrot seed production. Presented results from drip irrigated hybrid poplar plots.

Objective 1. To evaluate and refine microirrigation management strategies to promote natural resource protection and optimal crop production. A research SDI system at Colby, KS has performed well for 16 seasons with very little degradation in hydraulic performance. Three years of research on the effect of SDI frequency under deficit irrigation for corn, indicate that frequency does not affect corn yields on the deep silt loam soils of the Central Great Plains in the semi-arid climate. A four-year almond RDI (regulated deficit irrigation) study in CA was completed, and demonstrated the benefits of reducing irrigation during the hull split period to control hull rot disease and improve nut harvestability with no detrimental effects on overall productivity. Water savings using RDI were strongly dependent on soil conditions, with a documented water savings, compared to full irrigation requirements, of 65% under deep soil conditions. Under shallow soil conditions there were no water savings. Hydrus2D, model simulations were conducted in CA for 4 different pressurized irrigation systems; each associated with a typical crop. The study allowed for specification of root water and nitrate uptake, affecting the spatial distribution of water and nitrate availability between irrigation cycles. For each soil type and emitter type, the spatial patterns of water content and nitrate concentration were determined for various fertigation strategies, and leaching potentials were evaluated. The fate of pollutants from subsurface drip irrigation of septic tank effluent is being studied in soil-filled containers at the UC Davis Wastewater Treatment Plant. Data from the container tests are used to refine a model (Hydrus 2D) that predicts the adsorption and biodegradation of pollutants in the soil. The primary constituents of concern are nitrogen compounds. A volume balance ellipsoid based drip irrigation scheduling model was developed in AZ. It is currently being tested against drip irrigated chile and onions. The model allows the user to specify the shape of the ellipsoids based on the soil type and to specify the water holding capacity of the ellipsoid next to the emitter and then for the other four ellipsoids that make up the other depths. IA evaluated weather (ET) and soil (tensiometers) based irrigation scheduling methods for bell peppers grown with black plastic mulch and microirrigation, and showed equal performance for yield and fruit quality (IA). Both scheduling systems provided 80% of ETr. There were significant (P<0.05) variety responses to scheduling method with the Aristotle variety producing a 12% yield increase with the ET based scheduling system. In a FL citrus irrigation management study, irrigation was stopped on microirrigated Valencia oranges for 5 months in winter and early spring, 2004. Brix increased significantly which is economically beneficial. Irrigation was reduced by at least 10% by not irrigating in the winter. Research in NY showed that basal crop coefficients for apples related to grass reference ETo developed in arid climates are not valid for apples in humid climates due to differences in boundary layers of grasses and orchards. The coupling of the trees to bulk air makes air VPD and stomatal behavior more important than in grass. A modified apple-specific Penman-Monteith equation was developed that adjusts for the differences. This apple-specific model was better correlated to the measured tree water use than ETo. A simple irrigation schedule for strawberries is being evaluated on a LA research station. Soil moisture, water flow rate and weather variables are being analyzed to validate model. Several soil water probes (Echoprobe, EasyAg) are being evaluated in FL to see how well they measure soil water content under microirrigated citrus in Florida sandy soils. Both probes need soil specific calibration, but perform acceptably in sandy soils. Watermark soil moisture sensors and a Hansen data logger were demonstrated in Idaho as a tool for improved irrigation scheduling for sugarbeet production. Five grower fields were monitored and three were scheduled in 2004 using soil moisture sensor readings. Irrigation scheduled using soil sensors had fewer irrigation events. Harvest observations in two of the fields showed equal or greater yield with 2-4 less irrigations (3-6 less water). Four tape depths were evaluated in an SDI trial in NM with different field crops. Germination through SDI was not adequate for alfalfa at any tape depth. A small, two-row planter for potatoes was used to successfully obtain uniform plant stands in all tape depth treatments. Corn stands were directly related to tape depth ranging from a high of 98% in the 15 cm treatment to a low of 64% in the 30-cm treatment. Corn yield, was significantly different between tape depth treatments due significant stand differences. There were no significant differences between treatments for potato yield. Also in NM, ten hybrid poplar clones were evaluated for adaptation potential in the Four Corners region. Total ET amounted to 660 mm while total application was 686 mm for the 2 year old trees. A Minolta SPAD-502 chlorophyll meter was used to measure chlorosis. Clone OP-367 had the highest SPAD reading throughout the season. OP 367 was the tallest clone after two seasons reaching a mean height of 4.1 m and had the largest basal diameter of 9.1 cm. Objective 2. To improve, modify, and evaluate microirrigation system design and components for natural resource protection and optimal crop production. Lab tests in KS measured the effect of NH4-N concentrations in livestock lagoon water on required chlorine dosing to maintain a free residual chlorine level of 1-2 ppm. Lagoon water treated with acid reduced chlorine demand. Lab tests conducted to investigate the growth of biological organisms from livestock lagoon wastewater in a std drip tube and two others designed for use with wastewater showed no difference among tube types. A KS field study to evaluate clogging with four different heavy-wall microirrigation tubing products and livestock lagoon wastewater has shown that standard tubes have performed as well as tubes designed for use with wastewater. A new microsprinkler design (CA) has been developed, tested and patented. The design allows individual addressing, opening and closing of each microsprinkler emitter in a linear test array consisting of 50 sequential microsprinklers. Individual emitter activity is controlled remotely by a radio frequency controller powered by a solar panel. The design promises low cost, high precision delivery of water and dissolved solutes (fertilizers). Three years of field study to evaluate one, two, three, and four driplines per row of watermelon crop found no significant difference in watermelon yield, percent Brix (sugar content), crop cover, and leachate, in the very shallow (15 to 25 cm deep) Guam Cobbly Clay soil. However, automated irrigation scheduling, using switching tensiometers set at 25 cb, applied significantly more irrigation water under three and four driplines; there was no leachate under any of the treatments. Frequency irrigation was inversely related to the number of drip lines. Distribution uniformity (DU) was measured on 39 drip-irrigated strawberry fields in coastal California. The overall average DU was 80%. Factors that cause low uniformity included undersized lateral connections (spaghetti tube), too long of lateral length, unevenly set manifold valves, low pressure in the laterals, and too much elevation variation within blocks and fields. A database was developed of 312 microirrigation evaluations in CA carried out over the last 5 years. System (pump) pressures ranged widely; 60% of the systems operated at higher pressures than required, 30% operated at 10 psi higher than required, and the average potential pressure savings on 20% of the fields was 29 psi. Identified losses in the distribution system as a primary source of excess pressure loss, including extensive use of pressure regulation valves. Objective 3. To assess and develop decision criteria for adoption of microirrigation technologies. Seven years of field research in KS comparing SDI to simulated LEPA sprinkler irrigation indicated that LEPA performed better in 4 extreme drought years primarily due to higher kernels/ear and that SDI performed better in 3 normal to wet years primarily due to higher kernel weight. In TX, yield, water use efficiency, and various other parameters using SDI were greater than LEPA or spray irrigation for both cotton and grain sorghum for irrigation levels at 25% and 50% of full irrigation (i.e., full crop evapotranspiration); however, yield, water use efficiency, and various other parameters using LEPA and spray irrigation were either numerically or statistically greater than for SDI at 75% and 100% of full irrigation. A second season of cotton is nearly complete. SDI has also been compared with furrow irrigation of cotton for 3 years on a Louisiana research station using soil moisture meters to initiate irrigation. An increased yield from SDI was found in one dry year but not in two years with normal rainfall. Micro-spray irrigation has been compared with furrow irrigation of sweet potatoes for two years on a Louisiana research station using an ET-based scheduler. No significant differences in yields were found. Objective 4. To promote appropriate microirrigation technologies through formal and informal educational activities. Several workshops, seminars, field days, and poster sessions were presented on various aspects of microirrigation. These included: Water quality issues for SDI were presented at SW Kansas Ag Agent updates in Fall 2004; An SDI technology field day held at Colby, Kansas on Aug. 10, 2004 attracted 139 participants; 58 miscellaneous oral presentations, poster presentations, tours and discussions related to SDI by Freddie Lamm; Benefits of RDI were given to the annual meeting of the California Almond Board, and the California Dried Plum (prune) Advisory board; Sessions were presented to 197 growers at an Iowa winter conference, Jan. 30, and summer field day, July 12; A report on a new microsprinkler design and poster were presented at the Fertilizer Research and Education Program Conference, Tulare, CA September 2004; Explanation and demonstration of irrigation scheduling techniques for SDI, micro-spray and drip tape under plastic mulch has been provided for farmers attending annual Louisiana research station field days; Presentations given to several grape and apple grower and wine conferences in NY emphasized appropriate uses and amounts of irrigation for humid climates (this information has been incorporated into a new viticulture curriculum at Cornell University); More than 25 University of Guam students and 15 elementary school students visited the microirrigation field experiments at Yigo Agricultural Experiment Station; 6 workshops were presented (4 in English and 2 in Spanish) to CA strawberry farmers and irrigators, consultants, and irrigation dealers on ways to improve microirrigation system distribution uniformity; A technical presentation on Subsurface Drip and Spray Distribution Systems was presented at the VA Department of Health Advanced Onsite Training Conference, March 2004. A presentation on "Irrigation Technology. " was given at a regional meeting of the TX Agricultural Industries Association, Nov. 2004. Plans for 2005: Project members will focus on the milestones established in the new project (W-1128). Each of the 2005 milestones has one or more responsible members with an activity leader. Leaders will coordinate with others to obtain and compile information related to the milestones. Work will focus on an SDI survey, a report on guidelines for drip irrigation with wastewater, SDI installation and evaluation guidelines, and guidelines for ETbased scheduling procedures.

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In proceedings of the Central Plains Irrigation Conference, Kearney, NE., Feb. 17-18, 2004. Available from CPIA, 760 N.Thompson, Colby, KS. pp. 87-92. Martin, E.C. and M.K. ONeill (ed). 2004. Fourth Annual Four Corners Irrigation Workshop. July 10-11, 2003. Shiprock, NM. University of Arizona Technical Report. 51p. http://cals.arizona.edu/pubs/water/abe001.pdf