|Anderson, Randal - Randy|
Submitted to: Jointed Goatgrass Symposium
Publication Type: Experiment Station
Publication Acceptance Date: 3/1/2002
Publication Date: 6/20/2002
Citation: ANDERSON, R.L., BALL, D., WICKS, G., LYON, D., DONALD, W.W., MILLER, S. JOINTED GOATGRASS ECOLOGY BULLETIN EB-1932, 8 pp. Washington State University Extension Service. JOINTED GOATGRASS SYMPOSIUM. 2002. Interpretive Summary: Jointed goatgrass is difficult to control in winter wheat because they grow similarly and are related genetically. However, knowledge of jointed goatgrass growth characteristics enables producers to control this weed. The key to control is to reduce the density of jointed goatgrass seeds in the soil. This can be achieved by diversifying the rotation by inserting summer annual crops after winter wheat. Secondly, producers can favor winter wheat over jointed goatgrass by various cultural practices. Combining these tactics will cut jointed goatgrass density in future wheat crops 90 to 95%. Jointed goatgrass reduces the quality of wheat flour; foreign markets were refusing to buy infested grain. With these strategies, producers not only will improve grain yield, but also ensure a market of their grain.
Technical Abstract: Traditionally, managing jointed goatgrass in winter wheat has been difficult because of similarities in genetics and growth patterns between these two species. But knowledge of jointed goatgrass growth characteristics can help producers devise effective management tactics based on attributes of jointed goatgrass that are most vulnerable to control. With appropriate strategies, producers can reduce density of jointed goatgrass in their fields. The initial step is to lower the seed bank density. Lengthening the interval between winter wheat crops can lower jointed goatgrass seed density in soil up to 70 to 90%. A second crucial step is to strengthen the winter wheat canopy with cultural practices a strategy that can reduce jointed goatgrass seed production 45 to 60%. Combining these tactics will cut jointed goatgrass density in future wheat crops 90 to 95%. In areas where alternative crops are not practical, tactics that favor winter wheat over jointed goatgrass still minimize both wheat yield loss and seed production by jointed goatgrass. Lowering the density of jointed goatgrass also provides the added benefit of improving herbicide effectiveness.