Managing Irrigation for Optimum Efficiency
Almond growers in California have been relying on irrigation for more than 60 years. The Almond Board of California has supported University of California research on irrigation scheduling and management in a range of both high and low volume irrigation systems to determine the optimal use of irrigation water to enhance yields and quality, extend orchard longevity, suppress diseases and insects, reduce energy and optimize available water use.
Optimizing available water became a focal point during years of reduced water supplies. Funded by the Almond Board of California, University of California irrigation specialists have developed management tools for almond growers to optimize water use under various water availability scenarios.
Currently a variety of irrigation systems can be used by almond growers including drip, micro-sprinklers, sub-surface drip, solid set sprinklers and flood irrigation. The choice of an irrigation system depends on a number of factors including the types of soils, the variety of almonds grown, the disease and pest pressures, frost potential and protection, as well as the cost and availability of water.
To ensure that almond trees are neither over-, nor under-watered requires constant monitoring of a number of variables. The timing, frequency and amount of irrigation will depend on several factors, including weather conditions, the amount of water stored in the soil from winter rains, the stage of development of the trees and the orchard, the soil type(s), and the irrigation system type and efficiency.
Comprehensive scheduling should be keyed to three factors: (1) weather conditions driving evapotranspiration (Evapo-transpiration [ET] Scheduling) and use of a water budget approach with data provided by the California Department of Water Resources CIMIS program, (2) soil-based monitoring which can use a variety of techniques and equipment, and(3) monitoring tree water status using a pressure chamber (pressure bomb). Good, overall summaries can be found at the UC Drought Management website and the Irrigation Management module of the California Almond Sustainability Program (CASP).
Western Farm Press, July 2012, Irrigation Management and Scheduling, a Balancing Act
Western Farm Press, September 2007, Late-Season Irrigation Affects Almond Yields, Pests
2008 Almond Conference Presentation "Irrigation Scheduling - Putting It All Together For Efficiency and Production"
UC Davis Drought Management
Irrigation Training and Research Center, Cal Poly San Luis Obispo
Center for Irrigation Technology, California State University Fresno (Wateright)
Website ofDr. Larry Schwankl, University of California Cooperative Extension Irrigation Specialist
NRCS Web Soil Survey (information about an orchard's water holding capacity)
California State University-Fresno Center for Irrigation Technology Agricultural Pumping Efficiency Program offers subsidized testing through a PG&E program
California Irrigation Management Information System (CIMIS)
Irrigation Management, Terry Prichard, UCCE Emeritus Water Management Specialist, San Joaquin County
Kern County Irrigation Management, Blake Sanden, UCCE Kern County
Irrigation and Water Resources, Allan Fulton, UCCE Tehama County
Using the Pressure Chamber to Monitor Tree Water Status
Using Midday Stem water Potential to Refine Irrigation Scheduling in Almond
Measuring Crop Water Status in Orchard Crops
Tentative Guidelines for Interpreting Pressure Chamber Readings