Comparative chemical composition of armed saltbush and fourwing saltbush

Abstract

Armed saltbush [Atriplex acanthocarpa (Torr.) Wats.] and fourwing saltbush [A. canescens (Pursh) Nutt.] are browsed by livestock and white-tailed deer (Odocoileus virginianus Raf.). The objective of this study was to compare the chemical composition of these 2 shrubs growing together in south Texas. Leaves and stems from the outer 5 cm of current year's growth of each species were randomly collected from each of 5 stands in November 1985 and February, May, and August 1986. Samples were analyzed for crude protein (CP), calcium, potassium (K), magnesium (Mg), sodium (Na), phosphorus (P), and in vitro organic matter digestibility (IVOMD). Height and standing crop were also determined. Crude protein of armed saltbush leaves ranged from 32% in February to 19% in August. Fourwing saltbush leaf CP ranged from 24% in February to 12% in August. Armed saltbush leaves and stems generally had greater P concentrations than fourwing saltbush. Calcium, K, and Mg concentrations and leaf IVOMD of the 2 species were similar. Fourwing saltbush had lower Na concentrations and greater leaf standing crop than armed saltbush. Laboratory-determined values suggest that both species may provide nutritious browse for cattle and deer on saline rangeland.