A nasty weed is invading Minto – Giant Hogweed is a long lived perennial plant which quickly grows new plants through roots and seeds.
The plant is most commonly recognized when they have their large flowering stalks, but by this time the plants are already three or four years old. They tend to grow in open, undisturbed sites with abundant light, but can be found in woodlands or partially shaded forest edges.
“Making Minto residents aware of the problems of Giant Hogweed is vital to their health and safety,” said Mayor David Anderson.
“By putting up posters at grocery stores, post offices and recreation facilities, as well as including information on our website, the town is working to build awareness about this noxious weed to ensure our residents have as little contact as possible. The town is also seeking the assistance of our community to let us know where it is located so we can better control it.”
Although Giant Hogweed is not on Ontario’s Noxious Weed Control Act list, it was added to the County of Wellington’s list of noxious weeds last year. The sap of the Giant Hogweed, along with sunlight, can cause skin inflammation, burns and in serious circumstances, blindness if the sap gets into an eye. It is harmful to both people and pets.
Angelica and Cow Parsnip have a very similar leaf pattern and flower as Giant Hogweed. Angelica may be found in gardens grown as an herb while many farmers may be familiar with Cow Parsnip, which have been found in farm fields for decades.
However, Giant Hogweed is a relatively recent and insidious invader in the town that is being found purposely planted in gardens. Given the potential health affects, to be safe the town is recommending residents stay away from plants with similar leaves and flowers and asking them to notify the appropriate officials.
If members of the public find Giant Hogweed or have a concern about a plant they believe may be Giant Hogweed, they should contact John Benham, Weed Inspector for the County of Wellington (office 519-856-9828) or the Town of Minto at 519-338-2511. Information on Giant Hogweed is available on the Town’s website at www.town.minto.on.ca.
Last year, Wellington County council declared the plant a noxious weed.
That step came, after Wellington-Dufferin-Guelph Public Health sent a letter to county officials warning that the plant has spread into Wellington. It can be found throughout southern Ontario. Plants have even been reported as far north as Haliburton County. Giant hogweed can grow in a wide variety of habitats, however it is most often found along roadsides, streams and riverbanks.
It’s formal name is Heracleum mantegazzianum.
Giant Hogweed is a photo toxic plant. Its sap can cause phytophotodermatitis (severe skin inflammations) when the skin is exposed to sunlight or to ultra-violet rays. Initially the skin colours red and starts itching. Then blisters form as in burns within 48 hours. They form black or purplish scars, that can last several years. Hospitalization may become necessary for victims. Presence of tiny amounts of the sap in the eyes, can lead to temporary or even permanent blindness.
Keep kids away
Children should be kept away from Giant Hogweed, and protective clothing (including eye protection) should be worn when handling it or digging it. If skin is exposed, the affected area should be washed thoroughly with soap and water and the exposed skin protected from the sun for several days.
The Ontario Federation of Anglers and Hunters has posted information about invasive species. It states that for effective control, the plant should not be mowed, but rather sprayed with an herbicide at intervals until it is gone. Even after the parent plant is completely removed, the numerous seeds left behind can germinate seven to 15 years later, and ongoing monitoring is required.
Treatment
Those exposed to giant hogweed should:
– wash the affected areas immediately, with soap and water if available;
– keep affected areas out of direct sunlight;
– seek medical advice as soon as possible.
Council was unanimous in naming the weed noxious.
