A Big Stinkin’ Problem: Stinknet Invasion

Recently, there has been an invasion across southern Arizona that has made its way northward to Yavapai county: stinknet. Stinknet is an invasive species of wildflower that has been spreading across Arizona, and although some may find its yellow flowers attractive, it is doing untold damage to our native ecosystems. Stinknet establishes and spreads very rapidly, able to choke out native vegetation by forming large, dense mats and covering as much of the ground as possible. This also has the negative effect of massively increasing the fuel load of an ecosystem, allowing for more frequent and more intense fires. And as if this is not bad enough, the smoke produced by burning stinknet is also acrid, and can result in severe allergic reactions to both your skin and respiratory system.

The most notable part of the stinknet plant is by far the unfortunately attractive flowerhead, which is bright yellow and a perfect sphere. The plant also has deeply lobed leaves that are very similar to carrot leaves, except for the very noticeable odor they produce. The plants vary in size, being anywhere from 2 inches to 2 feet tall. The main look-alike is called pineapple weed, which has a similar flowerhead, except that the flowers are greenish, shaped like an egg, and have bracts cupping the flowerhead. 

We have had multiple reports down south in the Phoenix and Tucson area, but just recently I have also had reports of stinknet on the 179 heading towards Sedona and have even come across it myself doing fieldwork in the Verde Valley. If you come across it, the best thing you can do is report it to stinknet.org. If you are to remove it, be aware that it is NOT toxic to most people, but some have had rashes, so gloves and masks are recommended if you prefer them. As you are removing it, make sure you get the roots, and if the plant is flowering, put it in a bag to make sure that the seeds do not spread. If you would like to learn more and maybe get involved, please visit the same website you would make a report to: stinknet.org.

Upcoming calendar events from Yavapai County Cooperative Extension include our Extension Specialist Courtney Duchardt putting on “Ecology of Arizona’s Grassland Birds” on May 2, at Oak Creek Forest Service Visitation Center.  There are multiple presentations from the Yavapai County Master Gardeners on “Roots, Tubers and Bulbs” on May 12 at Jerome Historic State Park, “Home Landscaping with Native Plants” in Clarkdale on May 19, and “Intensive Gardening” at multiple libraries and dates across the county. Our Food Safety Program Coordinator, Tracey Waters, is also putting on a Virtual Food Protection Manager Certification Training on May 26 – 28, with registration ending on May 19. There is also a “Sourdough Bread Demonstration” hosted by Earl Duque and Tracey Waters on June 16, and registration ends on June 9. To stay up to date on Cooperative Extension events, be sure to check our events calendar at: https://extension.arizona.edu/local-offices/yavapai-county/calendar

Caleb Miller is an Assistant in Extension for Yavapai County Cooperative Extension where he is responsible for running the range program, predominantly through range monitoring.