Poison Hemlock

Asked April 20, 2020, 1:46 PM EDT

Can poison hemlock be composted in the city compost system?

Multnomah County Oregon

3 Responses

Thank you for choosing Ask an Expert for help with your composting question. Poison hemlock should not be put in the “green bin” or municipal composting system.

All parts of this invasive plant are toxic, even after being dried out. It is recommended that the plants be placed in a plastic bag, closed tightly, and placed in the trash.

Thanks for looking out for your community by checking on this.


Thanks for getting back to me about handling the poison hemlock. Any recommendations regarding tools and clothing you're wearing while taking these plants out and handling them?
Thanks much!

Several agencies comment on removing this plant by hand.

King County’s Noxious Weed Alert says, “Wear gloves and long sleeves. For small sites, pull or dig up plants. Remove entire root. Wash your hands thoroughly after handling plants.”

The Washington State noxious weed control board recommends, “Always wear gloves and protective clothing if working with poison hemlock as all parts of this plant are toxic.

For work in pastures, Oregon State University goes further, “Wear rubber gloves and a mask when handling this plant. On a hot day, the plants’ toxins may be absorbed into the skin.”

Protect yourself against danger from this problem plant.