Crop of the Week: Guayule

• Guayule (why-YOU-lee) is a woody plant that thrives in the deserts of the U.S. Southwest and Mexico. New clean technologies make it possible to extract natural rubber, latex, ethanol, nontoxic adhesives and other specialty chemicals from guayule.

• Guayule acreage in Yuma is small, and ranges from 50 to about 100 acres.

• Guayule is a renewable, low-water use industrial crop. Products from guayule are made using water-based processes that require no toxic chemicals. Guayule-based products are also biodegradable, high-performing substitutes for many synthetic, petroleum-based products that are often expensive to dispose of and hazardous to the environment.

• More than 2,000 species of plants can produce rubber. Guayule has been known as a rubber source since the pre-Columbian times when Indians of Mexico used it to form balls for their games.

• Guayule (Parthenium argentatum) is a relatively new commercial crop and the only rubber-producing species other than the Brazilian rubber tree (Hevea brasiliensis) that has been used for latex production on a commercial scale.

• Though guayule was commercially grown in the past during World War II when rubber imports from Southeast Asia were cut off, its resurgence in popularity came about during the 1980s AIDS crisis when a surge in rubber-glove usage revealed how many people were allergic to latex. Guayule-based rubber contains none of the proteins that cause latex allergies and is being developed for such latex products as medial examination gloves.

• The Yulex Corporation has the exclusive license to a patented process to produce latex and products from guayule.

• Research performed by USDA and private industry is finding uses for the 85 to 90 percent of the guayule shrub that remains after latex extraction. For example, a recent study showed guayule fibers to contain a type of natural pesticide to termites and, in addition, to be antifungal.

• The University of Arizona, in cooperation with the USDA-ARS, has maintained and evaluated plantings of guayule, the Chihuahuan desert-native shrub, for the past 10 to 15 years.

Source: Kurt Nolte is an agriculture agent and Yuma County Cooperative Extension director. He can be reached at knolte@cals.arizona.edu or 726-3904.