Integrated Management of Canada Thistle

Canada thistle (Cirsium arvense) is an aggressive, creeping perennial weed that infests crops, pastures, rangelands, roadsides, and non-crop areas throughout the northern and western United States. Several stakeholders, including organic growers and alfalfa seed growers have expressed their concern about the lack of viable management options for Canada thistle. The main goal of this project is to evaluate if the joint usage of pathogens, insects, and cultural practices can provide efficient, economically durable, and environmentally benign management of Canada thistle. To achieve this goal we have formed a multidisciplinary team composed of a cropping system specialist, an entomologist, and a weed scientist. We propose to complement field and greenhouse experiments with extension material for on- and off-farm presentations to illustrate the effect of synergistic interactions between biological and cultural practices on Canada thistle management.