Stripe rust development is currently being observed in experimental fields in the Pacific Northwest, according to recent field checks. While no rust has been found around Pullman, Washington, the disease has been identified in experimental fields in Walla Walla, Lind, Mount Vernon, Hermiston, and Central Ferry. Severity levels vary by location, with Mount Vernon showing high severity, while other locations like Walla Walla and Central Ferry indicate higher incidence and severity compared to the same time last year. Notably, a Lincoln County field where rust was present last November is currently clear. The Palouse region near Pullman is also currently rust-free, which is later than last year’s initial observation.
Considering the current stripe rust presence and favorable weather forecasts of high moisture and suitable temperatures, fungicide applications are now recommended for susceptible and moderately susceptible winter wheat varieties before flowering in the eastern Pacific Northwest. For spring wheat yet to be planted, resistant or moderately resistant varieties (ratings between 1-4) are advised. Fields already planted with susceptible or moderately susceptible (ratings of 5-8) spring wheat should consider fungicide application during herbicide treatment. Growers are urged to regularly scout their fields and apply fungicides promptly if active rust is observed or reaches a 5% incidence or severity. Nationally, stripe rust reports are relatively low compared to last year, with detections in Louisiana, Texas, Georgia, Washington (experimental plots only), and Oregon, but the potential for rapid development under favorable conditions necessitates vigilance.