Croftonweed (also known as eupatory, thoroughwort, sticky snakeroot, catweed, hemp agrimony, sticky agrimony, and sticky Eupatorium – scientific name Ageratina adenophora) is toxic to humans, horses, and other animals, and also produces chemicals that inhibit the growth of other plants. It spreads easily and crowds out native vegetation.
In 2019, we spotted a single clump of Croftonweed in Cobal Canyon, and since then we’ve seen it expand from a single clump to something like 50-100 plants. So wanted to get it out before it spread more and got even harder to remove. On October 4, a group of volunteers braved poison ivy to remove all the known Croftonweed from Cobal Canyon. We will have to keep an eye out for any sprouts that might come up from seed next spring, but basically, it’s Goodbye, Croftonweed!
Friends of the Claremont Hills Wilderness Park 