Land Plants - invasive

Giant Hogweed (Heracleum mantegazzianum) on Apr 10, 2025

Submitter has sample
EDRR Status: Local expert notified

Description of specimen

New sprouts already growing huge leaves. Hairy hollow stems with purple dots and splotches

Commentary

Thank you Charlotte for the report. Giant Hogweed (Heracleum mantegazzianum) and our native Cow Parsnip (Heracleum maximum) are very similar in appearance, but the size is very different. Giant Hogweed growing very much larger. Great observation finding this plant and photographing it. I will reach out for further information on specific site location with you.
Michael Blankenship, TCSWCD.

Michael Blankenship
April 11, 2025, 6:42 a.m.

Resources

There are many plants that look similar to giant hogweed, including our native cow parsnip. Giant hogweed is truly giant, often 7' to 14' tall, with leaves that can be up to 5' wide. There are some great photos comparing giant hogweed to similar species on the New York Dept of Environmental Conservation website.

Location

Lin some weedy grass alongside a gravel driveway between a relatively new development and a wooded resource area.

Expert Reviewer

Michael Blankenship
Tillamook Soil & Water Conservation District

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