Stinknet is true to its name: it’s a plant with an overwhelming and off-putting turpentine odor. Also known as Globe Chamomile, it has bright yellow flowers the shape of golf balls and carrot-like dark green leaves. It’s native to South Africa.
Stinknet was first recorded in California and Arizona in the early 1980s, with the first patch spotted in Tucson in 2015. In Arizona, the plant quickly spread northward throughout Maricopa County. It only recently appeared in the Verde Valley.
Stinknet grows in dense clusters, displacing native vegetation by infesting large areas along roadways. Thick patches are highly flammable, and the plant can cause severe allergic reactions.
The Arizona Department of Agriculture deems stinknet a “noxious weed” of concern. It emerges in late November and germinates continuously through May. Stinknet removal becomes nearly impossible after just two years of unchecked spread.
Fortunately, concerned groups like Friends of the Forest swiftly identified small patches of stinknet in Verde Valley. Only a few stinknet populations have been reported in the area, a result of efforts to detect the plant early and respond rapidly.
Proactive measures include hand-pulling or chemical treatments to limit the plant’s spread into disturbed areas, right-of-ways or trailheads. Land managers prioritize heavily-trafficked sites to minimize spread of both seed and plant material, preventing new populations from entering delicate zones like wetlands or wilderness areas.
For now, Arizona land managers - with some help from community members - have been able to stymie stinknet’s spread and protect native plant communities.
This Earth Note was written by Danika Thiele and produced by KNAU and the Sustainable Communities Program at Northern Arizona University.
