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From: Kitchener, ON
Region: Canada
Topic: Poisonous Plants
Title: What caused bump after walk in woods from Ontario
Answered by: Barbara Medford
Here is a list of the Poisonous Trees and Shrubs of Ontario. All three listed are native to Ontario:
Menispermum canadense (Common moonseed) - only berries are toxic if eaten. Pictures.
Toxicodendron vernix (Poison sumac) - all parts poisonous. Pictures
Toxicodendron radicans (Eastern poison ivy) - all parts poisonous. Pictures
Our personal opinion is that you probably were stung by some insect. Being in the woods near a stream, the best guess is a mosquito, but you could also have brushed against a plant with a spider or ants on it that didn't take well to your intrusion.
Our advice: if it has swollen more, spread to a rash, or you are having allergic reactions, see a doctor.
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