Mowing and slashing are not reliable as the plant is able to regrow and produce seed even at a height of . Biological control agents have limited success with "Carduus pycnocephalus". Insects that tested host-specific by the California Dept. of Agriculture and caused significant damage to the reproductive structures of the Italian thistle have not been utilized, due to concerns about possible predation of California's native thistle species. "Puccinia cardui-pycnocephali" is a species of rust (fungus) apparently exclusive to "Carduus pycnocephalus". Other rust species have been found on Italian thistle as well. Grazing by sheep or goats (not cattle) in Australia has showed promise as well. Chemical control can be achieved with a variety of products including: Clopyralid, glyphosate, Diquat, Picloram, and 2, 4-D ester. However, caution must be exercised when using these products, and their use is not always appropriate, especially near water surfaces and other sensitive natural habitats. Check with local, regional, and national regulations directing use.