Land Plants - invasive

Poison Hemlock (Conium maculatum) on May 25, 2026

Submitter does not have a specimen
EDRR Status: Local expert notified

Description of specimen

Described above. This area is a naturalization area that is unmaintained and likely has more hemlock. I will continue keeping a vigilant eye out and continue reporting as necessary. Thank you for your help with invasive species removal!

Commentary

None

Resources

OSU Extension: How to Manage Poison Hemlock

Location

There is a paved running trail directly behind these houses and there is a large patch of Conium maculatum on the side of the running trail, only about a foot off the trail. It's about 8 feet tall right now and in flower. I've tried contacting the Water Service company that has jurisdiction and they do not have an answering service or answer their phones, so I am reaching out to the county.
I'm sure it is known, but this is a deadly toxic invasive species.

Expert Reviewer

Avatar of Reviewer

Samuel Leininger
Clackamas Soil and Water Conservation District
4-County Cooperative Weed Management Area
Columbia Gorge Cooperative Weed Management Area

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