Knowledgebase

Poison Hemlock? #753072

Asked May 31, 2021, 1:35 PM EDT

Hi, I biked past some patches of this plant in Hillsboro. Could it be Poison Hemlock? Thank you, Kim McLaury

Washington County Oregon

Expert Response

Red-purple blotches on stems are a trait of poison hemlock, Conium maculatum. This page from Maine gives great details to identify giant hogweed look a-likes, including poison hemlock.

 An article from OSU Extension, this gives information about the plant in pastures.

Soil and Water Conservation Districts sometimes offer weed watcher programs, as with the Tualatin river, here.

Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied June 01, 2021, 12:50 PM EDT
Ok, thank you. Should I contact Washington County or anything since the hemlock, or what is most likely hemlock, is growing extensively along a roadway in NW Hillsboro?
On Tue, Jun 1, 2021 at 9:50 AM Ask Extension <<personal data hidden>> wrote:
The Question Asker Replied June 01, 2021, 7:24 PM EDT

Loading ...