Museum botanist Ken Marr says poisonous hemlock is an invasive species from Europe that it is becoming more common around the capital city.
Though a relative of parsley, if ingested the plant can cause paralysis and potentially death in people and animals.
Marr says that in 2002, two people cooked and ate hemlock — possibly mistaking it for parsley — and spent five days in hospital after going into respiratory arrest.
The Invasive Species Council of British Columbia says just 16 invasive species cost the agricultural and forestry industries in Canada an estimated $7.5 billion a year.
Those species include giant hogweed, with its highly toxic sap that can cause burns, blisters, and scarring of the skin, and Tansy ragwort, which is toxic to horses and livestock.
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