by David Ledger
Stinkwort is a fairly new invasive plant in California in the sunflower family that grows up to three feet tall with tiny heads of yellow flowers that bloom in the fall and when in seed, form a tufted head somewhat like a miniature dandelion. The stems and leaves are sticky and have a strong unpleasant smell and it can cause dermatitis although not as bad as poison oak.
It was first discovered in California in 1984 and has spread throughout the state. The plant is originally from southern Europe and northern Africa. It has become a fast-growing invasive in California and may spread like yellow star thistle. It can be toxic to sheep and cattle, although most cattle won’t eat it unless they are starving.
I found the plant pictured on the Westside Trail in Redding and pulled up about 15 plants that had just started to bloom. I came by a week later and many of the plants I pulled had flowerheads that had gone to seed. Now I know why they put them in plastic bags when sites are cleared of the plant with volunteers. I will point them out on the joint SEA/CNPS field trip on the Westside Trail on New Year’s Day. They may have been brought in by fire restoration crews or someone on the trail with seeds in their clothes. SEA and CNPS may do a stinkwort removal next fall if we have enough volunteers.