Giant Hogweed is a phototoxic plant.
Its sap can cause phytophotodermatitis (severe skin inflammations) when the skin is exposed to sunlight or to ultraviolet rays.
Initially, the skin colors red and starts itching. Then blisters form as it burns within 48 hours. They form black or purplish scars that can last several years.
Hospitalization may be necessary. Presence of minute amounts of sap in the eyes can lead to temporary or even permanent blindness.
And now this toxic plant has been found growing wild in Michigan.
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