Performance of Atriplex species in the San Joaquin Valley, California, under irrigation and with mechanical harvests

Abstract

Field studies were conducted in the San Joaquin Valley, California to evaluate perennial Atriplex species as multi-clipped forage crops under irrigated field conditions. Plants were first established using fresh water irrigations and then irrigated with saline drainage water (electrical conductivity, 18 dS m −1). Plant stands were cut and baled four times during the first 27 months of growth using conventional farm equipment. Analyses of ash, crude protein and fat, acid detergent fiber, neutral detergent fiber, lignin and macromineral contents were performed on bale samples collected from each species harvest. Estimated regrowth yields ranged from 2.2 to 5.3 t ha −1 year −1 for the species planted on areas larger than 0.25 ha. Those species, such as Atriplex deserticola Phil. and Atriplex undulata (Moq.) D. Dietr., which displayed relatively woody basal stems and were capable of producing adventitious roots appear to be more tolerant of multiple harvests, low cut heights and harvest traffic operations than those species not having the combination of these characteristics. Atriplex canescens (Pursh.) Nutt. regrowth forage provided the best combinations of low ash and sodium levels and low Na/K ratios.