Microsprinklers wet larger soil volume; boost almond yield, tree growth
Larry J. Schwankl
John Edstrom
Jan W. Hopmans
Luis Andreu
Kouman S. Koumanov
California Agriculture 53(2):39-43. DOI: 10.3733/ca.v053n02p39.
In the Arbuckle area of the Sacramento Valley, a 22-acre orchard was planted in 1990 with four almond varieties (‘Nonpareil’, ‘Butte’, ‘Carmel’ and ‘Monterey’). The orchard was irrigated with three types of microirrigation — surface drip, subsurface drip and microsprinklers. The orchard soils are 3 to 4 feet of gravelly, loamy sand overlaying a restricting clay layer. The coarse-textured soil with its low water-holding capacity allows little lateral movement of water from the microirrigation emission device. Under these soil conditions, microsprinkler-irrigated trees produced larger almond yields and showed greater tree growth. In addition, irrigation system evaluations show that all three microirrigation systems provide excellent irrigation uniformity levels after 8 years of operation with only routine maintenance.
L. Schwankl is UCCE Irrigation Specialist Department of Land, Air, and Water Resources, Hydrologic Sciences, UC Davis; J. Edstrom is Pomology Farm Advisor, UCCE Colusa County; J. Hopmans is Professor, Department of Land, Air, and Water Resources, Hydrologic Sciences, UC Davis; L. Andreu is Water Management Researcher located at the University of Seville, Spain; K.S. Koumanov is Water Management Researcher at the Fruit Growing Institute, Plovdiv, Bulgaria.
Support for this work was provided by the California Energy Commission and by BARD (U.S.-Israel Binational Agricultural Research and Development Fund). The authors extend their appreciation to Stan Cutter, field manager at the Nickel's Laboratory, for his excellent support and cooperation.