Giant Hogweed

Question: There is quite a lot of Giant Hogweed on the property I purchased last fall. My property is bordered by a creek, so I would like a way to eliminate the weed that is safe for me to use and not harmful to the environment. What advice can you offer?

responder: Bill Hutmacher  Replied May 31, 2023, 10:57 AM EDT
response: This plant is most likely Cow Parsnip, an Oregon native.   Not Giant hogweed.    Take a look at this comparison site - https://www.michigan.gov/-/media/Project/Websites/mdard/documents/pesticide-plant-pest/planthealth/hogweedvscowparsnip.pdf?rev=45092850ef7e4bc294f31137b3491fe0  Here is another site that reminds us that Cow Parsnip sap can be photo-toxic so if you decide to cut any down, please wear gloves and protective clothing - https://ckiss.ca/2016/07/difference-invasive-giant-hogweed-native-cows-parsnip/

responder: The Question Asker Replied May 31, 2023, 4:25 PM EDT
response: I had initially thought the same, due to the leaf shape, but revised my opinion when the stems matured and began to show purple spots. I viewed photos and descriptions on a number of sites, with Cornell’s site being most helpful. The risk in terms of possible harm to those touching the plant remains. And on the question of best methods of safe and effective removal, especially due to its proximity to the stream, I would like suggestions.

responder: Bill Hutmacher  Replied May 31, 2023, 4:42 PM EDT
response: If you believe it is giant hogweed (Oregon A list noxious weed), then you need to report it to the Oregon Dept of Agriculture Noxious Weed Control Program at this site - https://www.oregon.gov/oda/shared/Documents/Publications/Weeds/GiantHogweedBrochure.pdf     You should also contact Tillamook County Soil & Water Conservation District - Water Quality & Noxious Weed Asst Coord/Technician Michael Blankenship<personal data hidden>

responder: The Question Asker Replied May 31, 2023, 5:20 PM EDT
response: I had initially thought the same, due to the leaf shape, but revised my opinion when the stems matured and began to show purple spots. I viewed photos and descriptions on a number of sites, with Cornell’s site being most helpful. The risk in terms of possible harm to those touching the plant remains. And on the question of best methods of safe and effective removal, especially due to its proximity to the stream, I would like suggestions.

responder: The Question Asker Replied May 31, 2023, 5:39 PM EDT
response: I had initially thought the same, due to the leaf shape, but revised my opinion when the stems matured and began to show purple spots. I viewed photos and descriptions on a number of sites, with Cornell’s site being most helpful. The risk in terms of possible harm to those touching the plant remains. And on the question of best methods of safe and effective removal, especially due to its proximity to the stream, I would like suggestions.

responder: Bill Hutmacher  Replied May 31, 2023, 5:51 PM EDT
response: If you believe it is giant hogweed (Oregon A list noxious weed), then you need to report it to the Oregon Dept of Agriculture Noxious Weed Control Program at this site - https://www.oregon.gov/oda/shared/Documents/Publications/Weeds/GiantHogweedBrochure.pdf   You should also contact Tillamook County Soil & Water Conservation District - Water Quality & Noxious Weed Asst Coord/Technician Michael Blankenship<personal data hidden>

responder: The Question Asker Replied May 31, 2023, 6:57 PM EDT
response: Thank you for getting back to me. I reported it to Tillamook county nearly a month ago and filed a noxious weed report a couple weeks back. I have not heard from either entity. I will try again with the contact person for Tillamook county you suggest. Thank you for your response.

responder: The Question Asker Replied May 31, 2023, 7:17 PM EDT
response: Thank you for getting back to me. I reported it to Tillamook county nearly a month ago and filed a noxious weed report a couple weeks back. I have not heard from either entity. I will try again with the contact person for Tillamook county you suggest. Thank you for your response.