Toxic weed - Ask Extension
We and neighbors are having a surge this year of a weed that has a hairy, picky stem, growing to 3-4 feet tall. It has an unusual shaped flower bud th...
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Toxic weed #720205
Asked September 02, 2020, 12:51 PM EDT
We and neighbors are having a surge this year of a weed that has a hairy, picky stem, growing to 3-4 feet tall. It has an unusual shaped flower bud then turns into a white puffy deadhead. The weed makes skin turn red and itchy. There is a lot of it in brushy areas around power lines. It may be a type of lepidium draba. Not sure but how can we get rid of it? Thanks!
Kent County Michigan
Expert Response
Can you upload any photos to for a more positive identification? Images of the entire plant, flower and seed head and foliage would be helpful.
We look forward to hearing from you soon and assisting you.
Is there possibly a # that I could send a text to, with a picture attached?
Yes, of course. Please text photos to<personal data hidden>.
Thank you.
I just texted the pictures to your number. Thank you!
The weed photos you sent to Mary Wilson are American burnweed (Erechtites hieraciifolius), also known as fireweed or pilewort. It is a native, summer annual species in Michigan. I have not heard of people being allergic to this plant before, but many types of plants can cause irritation in people with sensitive skin.
Since it is an annual and you're already seeing evidence of seed production you'll want to physically remove as much of it now as possible to prevent more seed from entering your soil and the plant coming up next year. Since the seeds are attached to pappi (fluff) like dandelions, try to capture as much of that material as possible. If it is causing irritation I would suggest wearing long sleeves, pants, and gloves during removal.
Depending on the area you could use a herbicide like Preen that targets weeds germinating from seed next spring. You would not want to use this if you want to plant anything desirable in the area from seed. There are other herbicide options once plants have emerged as well, but again that depends on the desirable species nearby. Always remember to read and follow all labeled instructions before applying any pesticide.
On another note since you titled this "toxic weed." While fireweed is not known to be poisonous in the acute sense, it can cause liver damage if large amounts are consumed due to the alkaloid content. According an article in the Canadian Journal of Plant Science, this weed is reported to taste and smell bad which makes it unlikely that high enough quantities would be consumed to cause harm (Darbyshire et al. 2012).
If you'd like to discuss control options in more detail or have other questions, please feel free to contact me directly at <personal data hidden>
Since it is an annual and you're already seeing evidence of seed production you'll want to physically remove as much of it now as possible to prevent more seed from entering your soil and the plant coming up next year. Since the seeds are attached to pappi (fluff) like dandelions, try to capture as much of that material as possible. If it is causing irritation I would suggest wearing long sleeves, pants, and gloves during removal.
Depending on the area you could use a herbicide like Preen that targets weeds germinating from seed next spring. You would not want to use this if you want to plant anything desirable in the area from seed. There are other herbicide options once plants have emerged as well, but again that depends on the desirable species nearby. Always remember to read and follow all labeled instructions before applying any pesticide.
On another note since you titled this "toxic weed." While fireweed is not known to be poisonous in the acute sense, it can cause liver damage if large amounts are consumed due to the alkaloid content. According an article in the Canadian Journal of Plant Science, this weed is reported to taste and smell bad which makes it unlikely that high enough quantities would be consumed to cause harm (Darbyshire et al. 2012).
If you'd like to discuss control options in more detail or have other questions, please feel free to contact me directly at <personal data hidden>
