Photo by Mary Burrows, Montana State University, Bugwood.org
Yellow or stripe rust (Puccinia striiformis) is a disease of wheat, and will thrive on multiple hosts. In situations where stripe rust is prevalent, a 40% crop loss can occur. Stripe rust will infect winter and strip wheat - both are grown in Wyoming on a large scale. Stripe rust will affect all stages of plant development and is easily dispersed by wind. Its distribution in the United States varies year by year, depending on weather patterns.
The Wyoming Stripe Rust Survey was added to the Small Grains Ug99 Rust Survey conducted by the Wyoming CAPS Program in 2010. Wheat and barley fields are visually surveyed throughout the growing season. Any suspect material found is sent to the University of Wyoming, Department of Plant Sciences for further identification. Some fields are selected for a more intensive sampling effort, where twenty plants are randomly selected from each field for further examination. To date, stripe rust has been found in nine Wyoming counties.