Stinkwort (Dittrichia graveolens) is a very late summer–developing invasive annual plant. It’s difficult to reliably detect before July and it flowers beginning in September, ending only with the onset of cold weather. Stinkwort is a particularly objectionable plant because it provides no habitat or food for wildlife, it is toxic to some livestock and is avoided by all others, it grows along trails and in moist areas, and it is capable of causing humans a nasty rash comparable to poison oak. There is little to like about it.
Over several years of removing stinkwort from certain public and private lands, I’ve learned a few things:
- You can reliably avoid getting a rash by covering all skin that might come in contact, including wrists and hands. Occasionally cleaning tools helps too.
- Stinkwort should be removed before the plant flowers.
- Hand-pulling works best; weed-wacking does not work because plants regrow and produce seed if even a little bit of live stem remains.
- Removing all stinkwort, every plant, will eliminate a local infestation. Because there is a seed bank, albeit a short-lived one, this sometimes must be done for a couple of years.
- Even an experienced observer can’t see and remove all the small stinkwort plants in a large infestation; revisiting and removing stragglers is necessary.
- Educating and empowering others to know and care about managing weeds is a good investment of time.
Here are some benefits of removing stinkwort:
- You make the East Bay, our little corner of paradise, a better place.
- It feels good to perform community service.
- You meet new people.
- You get to know your local environment in a new way.
- You get as much exercise removing stinkwort as in a trip to the gym.
Are you inspired? Join me on one of my stinkwort forays, or I will visit you in your community and discuss how to approach your stinkwort. I will provide you with talking points for informing neighbors or requesting permission for access, and I will give you a copy of an informational brochure.
This is a great year to get started! OK, every year is a great year, but the drought has somewhat limited growth this year. Some of the areas I cleared (twice) last year have such reduced stinkwort populations that patrolling them is taking on the quality of a pleasant walk, with gloves and an occasional stoop to remove an errant plant.
As a postscript, I will speak more plainly. One person can’t do this alone, even for just one species in a small area of the East Bay.
More information? Contact Barbara Leitner, firstname.lastname@example.org.
— Barbara Leitner, former board member, CNPS East Bay Chapter, and stinkwort eradicator extraordinaire