Report Information:

  • Annual Meeting Dates: 11/14/13 to 11/16/13
  • Period the Report Covers: 10/2012 to 09/2013
  • Date of Annual Report Publication: 01/03/2014


Meeting Minutes:

Click here to view the minutes as a PDF - Requires Adobe Reader

November 14

The meeting was called to order at 8:30, and the draft agenda, was approved. A major component of the agenda was that state reports would be superseded by the need to discuss the new project proposal. Those present (A. Lakso, K. Morgan, C. Stanley, C. Corcos, M. Shukla, B. DeLeon, C. Shock, M. Bartolo, T. Trout, H. Neibling, S. Loring, J. Maloney, E. Roman-Paoli, M. Dowgert, A. Gips, F. Lamm, A. Garcia, D. Nandwani, K. Shackel, A. Fares, T. Robinson, and D. Porter) introduced themselves, followed by Comments from Dr. Loring (Administrative Advisor), highlighting the reporting process required for W2128, the process required for the new proposal (tentatively W3128), and new developments in AFRI/NIFA. Stakeholder representatives from 4 major irrigation companies addressed the group to discuss future directions in irrigation technology, and to stimulate discussion regarding the role of W2128/W3128 in these directions (a break was taken at some point during the following presentations).

Michael Dowgert and Ami Gips (Netafim) emphasized that at Netafim we want to know how to make drip irrigation simple, more reliable, and less complex so that there is greater drip irrigation adoption. Currently all systems are custom made. Could the installation be made simple so the overall system is easier and quicker to install? With lower cost more people would install drip irrigation. Drip irrigation is a much more than an irrigation system, it can be a management system for nutrients, weed control, etc. To make drip more attractive, how do we save water, manage nutrients, etc. and maximize yield? We have questions of how to enhance grower education. How do we develop better farmers? An example of the failure of drip irrigation was the adoption of drip among a certain group of apple growers who imposed too much water stress on the crop. We all know of failures that set back the adoption of drip irrigation. Just because drip is accepted for a certain commodity, it doesn't mean that the growers are getting the most out of the system. We want to extend education to growers, but manufacturers are among the least trusted sources of information. Growers do trust local product representatives. A past effort was to reduce drip irrigation system pressure. Overseas low pressure gravity fed systems have become very important, especially for 1 to 10 acre small farm systems in India, Turkey, etc. Low pressure systems have not taken off in the US.

Claude Corcos (Toro) stated that university research on drip has been essential to the development of the drip irrigation industry. The assumption that water is equally available to plants between field capacity and the permanent wilting point is probably not valid. The ideal crop water availability to plants is probably crop and climate specific. We need better understanding and tools to use drip irrigation to meet crop needs and maximize crop outcomes.

How do we get the most out of the drip irrigation system through irrigation scheduling? NDVI, CWSI, LWP, TTT, SWT, etc. With IR temperature imaging, you do not have to have sensors all over the field. What are the future algorithms? Water quality is a huge issue where irrigation has played an important role in water quality problems and can play an important role in water quality amelioration. Water supply and water use efficiency will become more important in the future, and hence a more robust model is needed to predict system success. In the area of materials sustainability, durability and recycling, overcoming insect and rodent damage would be very helpful. The failure of drip with alfalfa due to rodent damage is a well-known example. Energy reduction: Currently we use a lot of pressure in order to back flush the filtration system. Could the energy be recovered? Pressure regulating valves loose energy. Where could the energy be stored? Intellectual property: How do we best release intellectual property? An example of shared information is site specific fertilization with central pivot irrigation. An example of not sharing information: the large sweet potato growers in Israel do not share information and have hurt their yield, which collectively hurts their competitive position. (Ken Shackel mentioned that there is considerable pressure from the university administrations to extract intellectual property from university researchers.)

Bobby de Leon (Jain) stated that our focus is on the growers and our mutual success. We are trying to work with end users and what they are trying to accomplish. Internationally Jain has branched into seed, planting materials, and even micro finance to help assure the success of growers. Water resources are very limited in the US. Irrigated areas are increasing and decreasing in various parts of the country. Drip and micro irrigation has increased from 4 to 8% of the irrigated acres. For high value crops, drip is a much larger and more important part of the irrigated acreage. We are working on human resources within our company and of end users. Training and education is very important. Jain is investing in R&D and patent acquisitions. Jain is working on new production development, and trying to leverage global resources.

Jenny Maloney (John Deere) has been working on many aspects of drip irrigation including new crops. We have been trying to understand things from the customer's perspective. Perspective customers want to hear definitive answers, not "it depends." Drip irrigation information directly useful for growers needs to be consolidated and made more readily available. Education is really important for the future. Growers want to have concise results. It is really hard to extract useful concise results from research papers. John Deere financing is a major activity as a company perspective, but we have difficulty financing drip systems.

The use of tablets and I-phones is the main ways that our growers receiving their information. Key and useful information needs to be readily available via these formats. Growers want to see success next door. Brazilian growers do not want to know about the success of drip irrigation of tomatoes in California. They want to see success locally. Global trends:

More people are entering the middle class and will want to consume more vegetables, fruit, and protein rich food. These consumption needs will depend heavily on irrigated agriculture and drip irrigation. Water risk information is available with on-line ratings of water availability, quality, and regulation. Trends in US irrigation. Water available and regulation. Uncertainty in future prices. Changing diets? EPA edicts on fuel ethanol blends. Inconsistent rainfall. Water quality regulations, mandatory new rules in CA. China and India are investing heavily in irrigation. Key drivers for the adoption of drip irrigation, global perspective: 1. cost and availability of water. 2. value of the crop. 3. return on investment, and how long does it take to pay off the investment. Growers are more apt to adopt if they can pay off within 5 years. 4. Examples of local drip irrigation success. 5. The presence of local dealers who have full service to avoid failures (education of the dealer networks 6. Government cost share, eg. EQIP funding.

The near term future will be influenced by commodity prices, farm bill, water availability, water quality regulations, growth in row crops. Stability of production is also an important driver of the development of drip irrigation, for example sugar production needs to have greater stability for the sugar industry of Brazil.

Following these presentations there was a general discussion about what industry wants form the academic community.

Jenny: Growers want to have concise results. It is really hard to extract useful concise results from research papers.

Ami: Growers want applicable data at the field level. Some research papers are not really applicable; it is from a different world.

Michael: We need to get water to move upward in the soil, but how?

Steve: Problem of the hidden availability of published research.

Freddie: The IA knows little about the working groups and NIMSS. Fewer extension agents.

Jenny is a very good googler. She wants a really easy to use site for crop information. Jenny tries to compile the information.

Ali: The commodity groups compile their information.

Craig: It is a given at branch facilities, being relevant to the industry is a given.

Clint: The comments by Jenny and Steve on the problems of the availability of university research information is spot on. Much of the university information is on line, but its availability is very poor due to the way that information is archived, interlinked, and how urls are maintained. The university breaks linkages through their management of information.

Freddie: We have high tec and low tec micro irrigation and they are separated. Never the twain shall meet.

Ami: Growers all are operating at different skill levels. They need different tools.

Following the above discussion, Tom Trout described current research at the ARS Water Management Research Unit, Fort Collins. This was followed by lunch and Travel to Greeley Colorado for a tour of USDA - Limited Irrigation Research Farm, near Greeley, CO, and Onion producer, Fagerberg Produce Co., Eaton, Colorado. The meeting was adjourned at 5:30.

November 15

The meeting was called to order at 8:00. Dr. Loring announced that 1/15/14 was the deadline for the new project proposal, and brief reports of current research were presented by A. Lakso, K. Morgan, C. Stanley and K. Shackel. The rest of the day was devoted to a discussion of the new project proposal, and the group decided on the following title and 3 objectives:

Objective 1: Develop robust and appropriately-scaled methods of irrigation scheduling using one or more soil-, plant- or weather-based approaches.

Objective 2: Develop microirrigation designs and management practices that can be appropriately scaled to site-specific characteristics and end-user capabilities

Objective 3: Develop technology transfer products for a diversity of stakeholders to promote adoption of microirrigation

The meeting was adjourned at 5:00

November 16

The meeting was called to order at 8:00, and it was decided that all participants would send F. Lamm their proposed contributions to the new objectives by December 2. The business meeting followed:

Minutes from 2012 were reviewed and approved.

Kelley Morgan (UFL) was elected as incoming secretary for 2014.

The date and tentative location for the 2014 meeting was set for 10/22/14 - 10/24/14 in Nashville, TN.

The meeting was adjourned at 11:30.


Objective 1: Compare irrigation scheduling technologies and develop grower-appropriate scheduling products

The apple-specific Penman-Monteith (P-M) equation for water use for irrigation scheduling in the Northeast has been programmed into the daily calculations of the Northeast Climate Center at Cornell University (NY). It provides daily crop basal ET based on weather inputs from stations in apple-growing regions of NY and calculates water balance. Since it has been available online, many growers in NY have indicated interest, but the season in 2013 was particularly wet with consistent rains so few growers needed to irrigate.

Three alfalfa cultivators for hay production were grown on a sub-surface drip irrigated field using four irrigation strategies: 25, 50, 75, and 100 percent of ET with four replicates (WY). The experiment is conducted at the University of Wyoming Research & Extension Center in Powell, WY. Watermarks were installed at depths of 12, 18, 24, and 36 inches. The objectives of the study were to evaluate the effects of limited irrigation on dry-matter yield, water-use efficiency, and forage quality of alfalfa grown on a sub-surface drip irrigation system. The Watermarks at the depth of 18 were good indicator of irrigation water needs. No significant difference between varieties. Irrigation amount had no significant effect on WUE or forage quality, which showed very small decreases across irrigation treatments. This may evidence that even in times of water stress, good quality alfalfa can be produced when proper irrigation scheduling practices are followed that match water needs of the crop. A corn experiment was planted on a sub-surface drip irrigated field. The crop was submitted to three irrigation regimes, including full irrigated and 70 and 50 percent of full irrigated. Canopy temperature using infra-red thermometers (IRT)was monitored at each irrigations treatment. Our results show that IRTs were adequate tools to on the determination of water stress. A dynamic crop simulation model was used to mimic the experimental results. The crop model was not as effective as the IRTs to determine the onset of water stress.

A number of studies were performed in OR. A. Due to commercial interest in the manufacturing sweet potato fries, sweet potatoes were grown with various drip irrigation SWT criteria (25, 40, 60, and 80 kPa) were for potato yield and grade. Sweet potato yield and grade data was highest at 25 kPa for Covington and Beauregard and ay 40 kPa for and Evangeline. B. Irrigation criteria continued to be examined for seed production of 20 native perennial plant species that the US Forest Service and BLM have determined would be highly desirable for rangeland restoration. Each species was being grown in a semi-arid environment at Ontario, OR using subsurface drip irrigation in replicated plots with three irrigation treatments (0, 100, and 200 mm/yr total irrigation) repeated over years. Species requirements for optimal seed yield differed tremendously between species from 0 to 200 mm. None of the species needed more than 200 mm to optimize seed yield. In years of considerably above average rainfall (more than 300 mm) fewer species responded positively to irrigation. C. Onion response to drip-irrigation scheduling and criteria was examined. Onions are in storage to evaluate the irrigation treatments this winter. D.Optimize fertigation strategies for drip-irrigated onion. Onions are in storage to evaluate the fertigation treatments. E.Research was initiated on the irrigation criteria of annual native plants for seed production. F. Results of A-E above were communicated to growers by means of field days, workshops, grower meetings, written, and "on line" reports.

Results from a three year study of subsurface drip irrigated alfalfa indicated that the nutritional value of the alfalfa was affected by distance from the dripline and the irrigation regime (KS). Nutritional value was slightly increased at further distances from the 1.5-m spaced driplines and was slightly increased by reducing irrigation levels designed to replace 70 to 85% of the reference ET. A journal article concerning this research was published in Forage and Grazinglands.

A low pressure irrigation system was installed at the Agricultural Experiment Station to determine the suitability for irrigation to vegetable crops (VI). The system includes treadle pump, a water tank (250 gal.) at the height of 6 and drip lines. An observation trial on leafy greens conducted. Lettuce, kale and coriander were grown successfully. System will serve as a demonstration site for this technology in the U.S. Virgin islands. Second trial on watermelon was conducted using drip irrigation. Data on the yield and growth recorded. Variety 'Jubilee' was grown in a conventional management system in replicated design with four replications. Fertigation and chemigation applied to the fields when needed and weed control was done mechanically or with herbicide applications.

A 5 year water production function (WPF) trial for commercial almonds was begun in a total of 3 grower cooperator fields located in the north, central and south portion of Californias central valley (CA). In each location, irrigation levels ranging from 70% to 110% ETc are being applied, and both plant- and soil-based monitoring performed on a weekly basis. In this first year of treatment application, the 70% ET treatment reduced kernel size in all locations (from 8 -13%), but only the Kern County site exhibited a clear and progressive yield reduction (10%) from the highest to the lowest ET treatment. More severe carry-over effects are expected in subsequent years.

Objective 2: Develop design, management and maintenance recommendations for microirrigation systems

A subsurface drip irrigation (SDI) system was installed in a center pivot corner in May, 2012 using support from a USDA-NRCS Conservation Innovation Grant to determine the suitability of SDI for corn silage production under Idaho soil, climate, and harvest conditions (ID). Three drip tape depths and 2 tape spacings were installed. In 2013 corn silage was planted about 2 weeks later than the adjacent center pivot area, with irrigation on both areas managed by the farmer. At harvest, corn ear weight (highly correlated with total crop tonnage and feed value) was measured from all 18 plots. System performance and crop yield and quality will be measured for at least 3 years and the system will serve as a demonstration site for this technology.

An oral presentation with written paper was made to the annual international meeting of the ASABE concerning sediment transfer within driplines (KS). The results suggest that ASABE recommended minimum flushing velocity of 0.3 m/s is adequate for most microirrigation systems operating under typical conditions. This paper was extended and published in the Transactions of the ASABE. A one-hour webinar was presented on the Grange Network discussing the challenges and opportunities for SDI in row crop production. This webinar had both national and international participants and is archived for future viewings. An extensive portion of the seminar was dedicated to examining the minimum design requirements for successful SDI. An oral powerpoint presentations was made at the Governors Water Conference entitled SDI for Crop Production in the Great Plains - Approaching the 25th Anniversary of K-States Research and Extension Efforts which outlined progress made with developing this technology for the Great Plains. An oral presentation entitled SDI, the basics of successful systems was made to the North Carolina Irrigation Society. Joint technology transfer efforts concerning SDI involving Kansas State University, Texas AgriLife and USDA-ARS were continued in 2013. These efforts included presentations at local, regional and national meetings.

Objective 3: Develop best management practices for application of agrochemicals

Research continued on compensated root water uptake using partial rootzone drying (PRD) techniques (NM). The experiments were conducted using chile plants (NuMex Joe Parker; Capsicum annuum). Results supported previous observations that chile plants were able to take up more water from less water stressed part of the soil profile while maintaining the transpiration rate at the same rate as control treatment. No significant differences were noted in the plant heights between treatments. Water balance analysis showed that PRD techniques have a potential to be adopted as water saving practices in chile production especially for environments with limited water.

Two separate oral presentations were made to the annual international meeting of the ASABE concerning nitrogen fertigation for subsurface drip irrigated corn production (KS). The results suggest that kernel set can be enhanced by timely nitrogen Fertigation when irrigation is adequate or greater.

Objective 4: Evaluate use of non-potable water through microirrigation

Salinity responses and salinity-related suppression of budbreak of drip irrigated pecan [Carya illinoinensis (Wangenh.) K. Koch] seedlings under different irrigation water salinity levels were investigated in the pot-in-pot system (NM). No pecan seedlings under the irrigation treatment levels of 5.5 and 7.5 dS/m survived to the end of the 2-year growing period. Thus, threshold EC1:1 was somewhere between 0.89 and 2.71 dS/m beyond which plant injury increases with increasing EC threatening the survival of pecan seedlings. Paper was submitted to HortSci and is accepted for publication.

An oral presentation entitled Using Livestock Wastewater with Subsurface Drip Irrigation was made to the North Carolina Irrigation Society (KS).


Impact Statements:

  1. Direct measurements of apple and grape basal ET and magnitude of water stress in the cool humid climate of NY has provided NY growers with local general guidelines for irrigation. The new apple-specific ET model has been incorporated into an automated online system for NY growers to optimize irrigation. Since the standard ETo method makes errors of over-irrigation in cool years, the new model should save significant irrigation water for growers.
  2. Irrigation scheduling allows for a more efficient use of water, and the use of Watermarks is a viable strategy for irrigation scheduling of alfalfa in the WY region. Infrared thermometry is also a promising tool for irrigation scheduling. The prospect of properly determining the onset of water stress on crops encourages development of IRT-based tools for irrigation water management at commercial scale. The combination of IRT with other approaches might be an interesting approach to follow. The use of microirrigation for vegetable production at small scale is growing in WY. Among others, the use of drip irrigation in high tunnel production is on the rise in the region.
  3. Calibration of soil moisture instruments promotes improved irrigation scheduling with greater precision and confidence in OR. Crop yields have increased and water is being conserved. Groundwater nitrate contamination has been decreasing continually over the last decade in OR.
  4. Presentations of SDI research results in KS reached approximately 150 participants in various venues potentially impacting irrigation management on a large land area in the Central Great Plains and beyond. Adoption and successful use of subsurface drip irrigation systems is being enhanced in KS by extensive and robust technology transfer efforts in the Ogallala region.
  5. In USVI, lettuce and kale varieties produced marketable heads in a low pressure irrigation system, which was demonstrated during World Food Day. Growers were enthusiastic about the system for vegetable production. In watermelon, var. Jubilee produced marketable and quality (brix) fruits. In USVI, drip irrigation has been very beneficial for the farming community and our variety trials of vegetables. The use of drip irrigation is a great asset when it comes time for the application of fertilizers.
  6. In CA, development of a generalized water production function will allow water use to be based on an objective crop per drop basis. Based on the results of the CA study, we will be able to put a price tag on the benefits and problems associated with both over- and under-irrigation in almonds.
  7. If SDI can be shown to be a cost-effective irrigation system for corn production on center pivot corners (ID), it will provide additional conveniently-located acres to help meet demand for corn silage while minimizing labor, energy use, and water use on the SDI area. It will also protect surface and ground water as well or better than any other irrigation system.
  8. Better use of irrigation systems and irrigation criteria for onions are increasing onion yields and reducing environmental consequences of onion irrigation in OR. Drip irrigation is used locally on 50 percent of the acres and accounts for over 50 percent of the local production. Combining drip irrigation with careful irrigation scheduling reduces the negative environmental consequences of onion production: water and nutrient applications are very close to the actual needs of onion and nitrate does not leach to groundwater. Nitrogen application rate to drip-irrigated onion in OR has decreased by half as yields have increased. Groundwater water quality is improving in OR over the entire onion production region of the Treasure Valley.
  9. Experimental results in NM showed that partial rootzone drying technique has the potential to be adopted as water saving technique in chile production systems.
  10. Documentation and discussion of SDI flushing hydraulics in KS will lead to less costly microirrigation designs and also improved maintenance of SDI systems.
  11. Pecan root initiation and growth, and development and survival of young Pecan trees are found to be sensitive to soil salinity.