2003 Annual Meeting Minutes W-128
Davis, CA (Oct. 22-24, 2003)
Wednesday, October 22, 2003
Meeting was opened by Larry Schwankl at UC Davis. Members present were LeRoy Daugherty (Admin Ad.), Larry Schwankl, Clint Shock, Craig Stanley, Gary Clark, D. J. Mills, Jan Hopkins, Freddie Lamm, Bruce Lesikar, Howard Neibling, Mick O’Neill, Larry Parsons, Clare Prestwich, Ken Shackel, Prem Singh, Hank Taber, Muluneh Yitayew, Elvin Roman, and Tom Trout.
LeRoy Daugherty, Administrative Advisor, discussed the new format for Multistate Research Proposals. The new procedure will be electronically submitted and will include objectives, impacts, and milestones. Emphasis should be placed on multistate cooperative projects. The project will be peer reviewed. There will be a stronger emphasis on accountability and stakeholder input. There is also interest in including extension and outreach in the proposal. Each person who wishes to become a member needs to initiate the Appendix E for membership and check with his Experiment Station Director.
State Reports:
Gary Clark (KS) reported on drip tape output in relation to temperature. Several drip tapes were evaluated at temperatures ranging from 20 to 60 C and pressures from 8 to 12 psi. Increase in water temperature increased emitter discharge rate for one tape but had a slight decrease in discharge rate for another tape. Thin wall (8 mil) tapes showed a large increase in discharge rate at temperatures above 50 C. Thicker wall (15 mil) tape showed a more linear response. Other tests involved biocide treated drip tapes and determining chlorine dose requirement for treated livestock lagoon wastewater. Biocide
Ken Shackel (CA) reported in pressure chamber measurement of midday stem water potential for prunes. Project developed target midday values for RDI. Irrigation was scheduled on level of stress in trees. Website called Water Right uses average weather data and gives suggested irrigation schedule. Full irrigation baseline was compared with target irrigation line. Trees use less water when they are in moderate stress. Basing irrigation schedule on water status of plant can save water. Water saved with deficit irrigation was over 50% or about 15 acre inches. This method probably mines water from the soil. Excess irrigation produces more vegetative growth and not necessarily more fruit production. If grower can save one irrigation, this method can pay for itself.
Freddie Lamm (KS) discussed conceptually how one can predict the annual irrigation amount. Irrigation amount is a function of ETc, rain, season length, initial soil water, maximum allowable depletion, soil water holding capacity, and irrigation system capacity. This approach is applied corn to allocate water. If we can predict irrigation, we can predict yield. Template was developed to evaluate planned number of acres planted to corn. This program predicts net return per acre. Discussion continued on costs of subsurface drip irrigation vs. other forms of irrigation.
Prem Singh (Guam) reported on emitter clogging problems in popular drip irrigation (five types of tubing). Irrigation water is high in carbonates. More clogging occurred with Chapin Turbulent Twin Wall (51.7% decrease) and Netafim Typhoon 20 (12”) (27.6% decrease). Field studies on Optimal Wetted Soil Volume for watermelon using different numbers of tubes per bed (1, 2, 3, or 4) showed no difference in yield among tube treatments and water use efficiency was highest for the 1 tube treatment. Two tubes per bed is the recommendation to ensure good fertilizer and water distribution.
Jan Hopkins (CA) reported on soil water dynamics in root zone of micro sprinkler-irrigated almond trees. Specifically, root water uptake models (1-D, 2-D and 3-D). He presented sprinkler uniformity data for under tree and showed that very non-uniform application occurred from “spoke-type” micro sprinklers. Jan presented data for a 2-D and root water uptake models and flexibility for use. Used an optimization technique to minimize differences between measured and predicted values, resulting in an improved simulated root distribution and water uptake picture. Virtually all water uptake occurs only above 0.4 m depth in the soil profile.
Hank Taber (IA) reported on various items – microirrigation scheduling for greenhouse tomatoes (Amish growers using no electricity), N injection for peppers for Iowa growers who want to have steady supply of peppers throughout summer, and field day (outreach efforts) and sweet corn and pepper irrigation scheduling (research efforts). He looked two emitter spacings and three scheduling methods. The goal was to maintain a 10 cb soil moisture regime that failed to be maintained with each treatment combination.
Freddie Lamm led discussion on the revision of the Project
CURRENT OBJECTIVES TO BE REVISED – THESE MUST CHANGE FOR NEW PROJECT
1. To evaluate and refine microirrigation
management strategies to promote natural resource protection and optimal
crop production.
2. To improve, modify, and evaluate
microirrigation system design and components for natural resource protection
and optimal crop production.
3. To assess and develop decision
criteria for adoption of microirrigation technologies.
4. To promote appropriate microirrigation
technologies through formal and informal educational activities.
LeRoy Daugherty stated that milestones and coordinated efforts among states need to be included in the new proposal. Considerable discussion resulted as to how to approach revision of the project and centered on the following working title and objectives:
Reducing Barriers to Adoption of Microirrigation
1. Identify and Assess Significance from
industry (perceptual, technical and management barriers)
- survey growers, Mfg, consultants, designers
2. Existing technical barriers
- clogging
- physical performance
- wastewater
3. Management Barriers
- Irrigation scheduling
- Water quality BMPs
- Urban uses of microirrigation
- Nutrient management
Meeting was adjourned for the day at 6:00 PM
Thursday, October 23
The group met at 7:45 AM for the field tour which began with visiting an almond orchard irrigation study site investigating different irrigation methods ( microsprinkler, SDI, surface drip, single lines, multiple lines). After lunch we traveled to visit a vineyard in Napa Valley (Mondavi Winery). Thibaut Schlasch (Research Viticulturist) explained research on using controlled stress to improve quality of wine grapes. Measurements of stem water potential and soil moisture monitoring were use for irrigation scheduling decisions. After the field site visit, Thibaut hosted a wine-tasting session at the Mondavi winery.
Friday, October 24, 2003
Meeting was convened at 8:00 AM
It was decided to continue work on the project revision and rewrite. Clint Shock began with procedures for written state reports submittal for 2003. The group expressed thanks for the great tour on Thursday and Clint said he would get something for us to sign to send to those who participated in the tour.
Larry S. suggested that Vice Chair be responsible for putting together the annual report and President plan the next meeting.
Next meeting – discussion centered on Nov. 14-16, 2004 (Irrigation Association Meeting in Tampa, FL) Nov. 16-19 (Tues-Fri) (W-128) or April 2005.
Ken S. moved Howard N. seconded to plan during the meeting for Nov. 16-19, 2004 following the IA meeting – motioned passed.
Ken S. moved that Gary Clark be nominated as the new Secretary of W-128. Motioned passed.
After lunch, H. Taber moved , K. Shackel seconded, that the minutes from the 2002 Meeting be approved. Motion passed.
C. Shock asked that report input for annual report to be submitted to him by Nov. 7.
New Proposal
Gary Clark presented a draft of objectives explanation/justification. Considerable discussion continued to refine objectives and procedures and determine how different states plan to participate in specific objectives. After several iterations and much discussion the following objectives and writing assignments were proposed:
Proposed Working Objectives:
1. To identify and assess the significance
of barriers to adoption of microirrigation.
Writing Coordinator, Freddie Lamm, flamm@oznet.ksu.edu
2. To reduce technical barriers associated
with microirrigation system design, performance, and maintenance.
Writing Coordinators, Gary Clark and Larry
Schwankl, gac@ksu.edu ljschwankl@ucdavis.edu
3. To reduce existing water and nutrient
management barriers associated with microirrigation.
Writing Coordinators,
Sub objective a. Irrigation scheduling,
Ken Shackel, kashackel@ucdavis.edu
Sub objective b. Water and nutrient redistribution
and management,
Craig Stanley, CDS@mail.ifas.ufl.edu
Deadlines for developing the new proposal:
October 28 – Objective leaders have outline
completed
November 3 – E-mail to participants for
input into the objective outlines
November 10 – Responses from participants
for specific objectives due
November 26 – Objective leaders’ input
due to Freddie L./Larry S.
December 19 – Final version of proposal
due
December 19 – Participants should contact
Ag Exp. Stn. Dir of intent to participate
January 15 – Formal review process begins
State Reports continued
Tom Trout (USDA-ARS (CA)) – presented information on mobile lab evaluations (with respect to energy conservation) of systems in strawberry, almond, production operating pressures, pressure losses in distribution, filters, valves, regulators, etc. No gain was observed for using higher pressure. Energy $ savings for high value crops minimal, but efficiencies can increase with more efficient designs. Irrigation distribution uniformity survey for strawberries – 45% to 95 %. Problems – sloping beds, length of run, connections too small, unevenly set manifold valves, emitter variability, and too low system pressures.
Clint Shock (OR) – asked question as to what should be the frequency of application to achieve optimum crop production. Growers don’t irrigate as frequent as research plots do, but increased time of application as ET increases during the season. He requested input as to the effect of less frequent but more volume applied. Discussion revolved around advantages and disadvantages of either scenario.
Howard Neibling (ID) – reported on SDI and irrigation scheduling. Gopher problems had to be overcome and determination of depth for SDI. Pit studies were conducted to determine wetting patterns (resulted in 12” diameter spread). He discussed studies to determine best tube spacing, type of tube, depth, etc. Also, he presented information on using soil moisture sensors for irrigation scheduling for potato production.
Larry Parsons (FL) – reported on citrus microsprinkler irrigation with different coverage patterns (diameters) for production effect (25, 50, 75, 100%). More water was applied with the larger areas covered. Some difficulty was expressed because of malfunctions and the design which allowed different amounts of water applied to each coverage treatment.
Mick O’Neill (NM) – reported on SSD on crop production – different depths, crops in rotation. Used furrow bottom as reference for depth of tube installation since bed height isn’t the same for each crop. Surface water source has been experiencing low to no recharge over the last two years. Potatoes good stand, alfalfa – poor stand. Corn stand establishment was most responsive to depth of tube (the shallower the better). Alfalfa showed no yield response to depth of tube treatments. Gophers are a major problem. Used surface drip on poplar tree production – shows great potential to become significant crop. Determined ET for 1, 2, and 3-year poplar crop and compared to ET reference (alfalfa). Evaluated different clones for growth characteristics. Gopher problem not as great – heavier tube used. He also reported on using low tech- low cost drip systems for Navajo farmers.
E. Roman-Paoli (Puerto Rico) – not current active member but wants to get involved (Objectives 1 and 4 - current project). Reported work on onion on spacing and frequency of application, SDI on eggplant, and N injection on coriander. Citrus and avocado – soil moisture levels (tensiometer) for irrigation scheduling and ET replenishment on tanier and tanier root rot syndrome. Planned work includes continuation of work on fruits and yams, fertigation on sweet cherry peppers, distribution uniformity for vegetable production on plastic mulch, and herbicide application through drip system
Craig Stanley (FL) presented information on studies to develop solute movement models for microirrigation use in raised plastic-mulched bed for vegetable production. He, also, reported on work using GIS techniques to aid in irrigation scheduling decisions for subirrigated sod production.
Meeting was adjourned at 5:30 PM
These minutes are respectfully submitted,
Craig Stanley, Secretary
W-128 Multi-state Research Project