Yellow Starwhistle
Yellow starthistle is a widespread problem in Northern California but land managers at Yolo report promising results in preventing yellow starthistle from taking over the ranch and destroying valuable grazing land. According to Casey Stone, approximately 15 - 25% of the 7,500-acre Yolo ranch is infested with yellow starthistle. "It will eventually take over an area and crowd out everything," he explains. The weed chokes the growth of native grazing plants, and its spiny thatch is difficult for dogs and horses to maneuver through. A variety of weed management methods have been tried at Yolo including biological, chemical, and mechanical control, all of which are used primarily on flat terrain. Chemical control methods have proven the most effective for the Yolo Land & Cattle Company and have been used extensively by the Stones to stop yellow starthistle in its tracks. They have achieved success in controlling the weed by rotating the use of chemicals to avoid weed resistance. Greatest success was achieved by applying chemicals every other year, and performing controlled burns whenever possible.