Land Plants - invasive

Poison Hemlock (Conium maculatum) on Mar 11, 2025

Submitter does not have a specimen

Description of specimen

Hundreds of individual plants located along the east shoulder of SW Canyon Drive starting near the intersection with SW Canyon Ln. and extending northwesterly for approximately 100 yards. Photo below was taken in May of 2024. New growth as of March 12, 2025 is already 8 to 12 inches tall.

Commentary

Thanks for the report Doug! Your picture isn't detailed enough for me to confirm that it is poison hemlock, but it is common throughout the county.

If this roadside is a county road you can file a report with the county at https://forms.co.washington.or.us/form/request-road-service

More information about the weed can be found at:
https://tualatinswcd.org/species/poison-hemlock/

Here's a best management practices guide should this plant appear on your property.
https://tualatinswcd.org/poison-hemlock_bmp/

If you have more concerns. Please reach out.

Keith Nasman
Invasive Species Technician
Tualatin Soil & Water Conservation District
971-330-0902
keith.nasman@tualatinswcd.org

Keith Nasman
March 13, 2025, 1:18 a.m.

Location

Hundreds of individual plants located along the east shoulder of SW Canyon Drive starting near the intersection with SW Canyon Ln. and extending northwesterly for approximately 100 yards. Photo below was taken in May of 2024. New growth as of March 12, 2025 is already 8 to 12 inches tall.

Expert Reviewer

Keith Nasman
Tualatin SWCD

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