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Giant Hogwood Alert
Click here the Pennsylvania Hogweed 4 Page color brochure.
Click here to see additional pictures of Giant Hogweed (will take some time to download)
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Photos by David Marrison, OSU Extension |
Summary of Giant Hogweed Found in Ashtabula County
Each year we encounter new diseases, weeds, and insects that we must identify and determine their threat level. Farmers and homeowners alike are getting more familiar with such recent pests as the Soybean Aphids and Multi-colored Lady Asian Beetles. Then, last year a new invasive weed pest emerged in northeast Ohio. This being hogweed. Please read on as you may have stumbled upon this weed.
This new plant is Heracleum mantegazzianum better known as Giant Hogweed. This huge plant is a member of the carrot or parlsey family and was introduced into Europe and North America in the early 1900s. This plant is most easily identified by its large clusters of small flowers that appear around the beginning of July. These flowers are absolutely gorgeous as they cluster together to form a topped umbrella shape that can span close to three feet across. This plant can grow up to fifteen feet in height and have a four inch stem. Its hollow stem has distinct purple blotches with coarse white hairs that circle the stem at the base of the leaf stalks.
The leaves are lobed, deeply incised and can measure up to five feet across. This plant's name comes from Hercules of ancient mythology and it truly lives up to its billing. Folks, this weed is a beast!
Because of its massive size and appearance, this plant was cultivated and transferred between many arboretums and personal gardens. Unfortunately, this plant has spread from these gardens and has become established in roadside ditches, stream banks, vacant farmland, and along tree lines. In the United States , it is known to occur in eleven states and is now listed as a Federal Noxious Weed making it unlawful to propagate, sell or transport. Our neighbors in Pennsylvania have become the hot spot for this weed. In fact, our neighboring Pennsylvania counties, Erie and Crawford, each have over 100 sites where this plant has been identified. Given its proximity, it was only a matter of time before this plant started showing up in Ashtabula County . Just in the past few days, hogweed has been spotted in Andover , Austinburg, and Jefferson Townships and in the heart of Ashtabula Harbor. (in Ashtabula County)
So what is the big deal about this plant? Karl Valley from the Pennsylvania Department of Agriculture reports this plant is a public health issue because of its potential to cause severe skin irritation. This plant functions in the same manner as poison ivy as the sap can produce painful, burning blisters within one to two days of contact. These juices can also cause painless blotches that develop into purplish or brownish scars that can persist for several years.
So what can we do to help? The USDA-APHIS office is requesting you check your property for Giant Hogweed. Many folks confuse this plant with cow parsnip ( Heracleum lanatum ), Angelica ( Angelica atropurpurea ) or Poison Hemlock ( Conium maculatum ). If you believe this noxious weed is on your property, APHIS will work with you to discuss management strategies. Folks are cautioned about mowing, cutting or weed wacking this plant as its large taproot will soon send up new growth. Additionally, it will place you in risk of coming in contact with the plant's sap.
If you would like a brochure on Giant Hogweed or would like to receive the contact information for the local office of the USDA-APHIS office, please call our office at 440-576-9008 or click the following link
photo courtesy of USDA-APHIS
David Marrison is Extension Educator, Agriculture & Natural Resources, Ohio State University Extension. Mr. Marrison can be reached at 440-576-9008 or marrison.2@osu.edu
