Research to combine Ceutorhyncus with herbicides or mowing has not been conducted. Research has shown that biological and chemical controls are compatible for musk thistle. This is most likely true for Canada thistle as well. Ceutorhyncus litura is available through the Colorado Department of Agriculture. Urophora cardui is another biocontrol insect available from the Colorado Department of Agriculture.
Females lay eggs on apical meristems of developing shoots.
Larvae burrow into shoots. Their feeding triggers huge galls to form that stress the plant, perhaps killing it. 1 Colorado State University Cooperative Extension weed science specialist and associate professor, bioagricultural sciences and pest management. Go to top of this page. Updated Wednesday, May 02, 2001.