Giant Hogweed Identification
Voiceover: Giant Hogweed isn't new to Ontario, but it has become a growing concern for landowners. This invasive species can suffocate local vegetation and pose a serious health risk to people who come in contact with it. Giant Hogweed sap causes severe dermatitis; or burns and blisters on the skin. This sensitivity can last for several years after exposure. Landowners and citizens alike need to understand how to identify this species if they see it in their communities.
Mike: So at this stage we want to be able to ID this plant and there's kind of two really distinguishing things about giant hogweed. First and foremost is its stalk; and you can see two things-there's a bunch of purple blotches and purple speckles and then secondly it's really coarsely hairy-almost like a huge series of whiskers. So that kind of purple blotchiness is pretty unique, not a lot of species have that-so that's clue number one. Clue number two is this really unusual toothed, jagged almost weird looking maple leaf - it's quite serrated, jagged and toothed edge - and it's about 30 centimeters in diameter in early May. So two things-one the blotchiness of the stem and all the coarse hairs and secondly the really jagged leaf.

Voiceover: Early identification is critically important. Although it's only 30 centimetres tall in May, Giant Hogweed can grow to a towering 15 feet by August.

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