Rubber Rabbitbrush (Chrysothamnus nauseosus) a multi-use desert shrub

Abstract

Chrysothamnus nauseosus (Rubber Rabbitbrush) is a semi-arid shrub in the Western United States. It grows in a wide range of environmental conditions including saline soils. It has a high rate of photosynthesis and does not become light saturated at full sun. It has potential uses as a revegetation shrub, forage for wildlife and livestock, production of natural rubber, hydrocarbons from its biomass, resin for polymer plastics, a landscape shrub and a potential source of chemical compounds. In terms of forage value, subspecies of Rubber Rabbitbrush contained 9-13{\%} crude protein and 0.140.22{\%} phosphorus. The in vitro digestibility ranged from 36-55{\%}. The natural rubber content ranged from 1-6.5{\%} in the older wood. The resin content in the new tissue ranged from 5-38{\%}. The rubber content is inversely correlated with the resin content. The highest rubber content occurs during the high stress period of the summer whereas the highest resin content occurs in the low stress periods of spring and fall. The average molecular weight of the rubber is 585 000. As a potential source of hydrocarbons from biomass, Rubber Rabbitbrush was rated highly in comparison to other desert shrubs.