Look out for an invasive plant named hogweed, which is among the most dangerous plants in Canada, according to the Nature Conservancy of Canada.
The plant can cause third-degree burns and even blindness. It’s a non-native plant that grows up to six meters in height, and it has white flowers at the top. Their sap is clear and toxic, causing rashes, blistering, burns and even blindness if it touches a person’s body and then that area is exposed to the sun.
The Nature Conservancy of Canada asked people to document sightings of the plant, which is now flowering. Until now, the plant was found in the Atlantic provinces, Quebec, Ontario and British Columbia and cities like greater Toronto and Ottawa.
Three years ago, five children in England were burned in two separate incidents after touching giant hogweed in public parks.
Dan Kraus is a biologist with the conservancy, saying that it’s most likely the Asian species of the plant arrived in the 1940s, considered to be an ornamental plant.
It Spreads Fast and Damages the Native Vegetation
The plant looks like the cow parsnip, and it grows in gardens, close to the roads, in ditches and on the shores of rivers and streams.
Kraus stated that the plant spreads quickly:
“A single plant can produce thousands of seeds and it can spread quickly. The seeds are dispersed when they fall into rivers and streams, and can be dispersed short distances by the wind. Because it’s a tall perennial, giant hogweed can take over large areas along rivers and streams, shade out all of our native vegetation and actually nothing can grow under it sometimes.”
The plant was also spread in Europe, causing erosion and threatening the salmon spawning habits in the UK, added Kraus.
However, experts explain that just touching the plant is not dangerous. The sap is toxic, and it reacts to sunlight. After exposure to the plant, washing the body and clothes can prevent the chemical reaction.
Kraus also encouraged the public to use the app iNaturalist.ca to report sightings of the giant hogweed.
Andre Blair s is the lead editor for Advocator.ca. He holds a B.A. in Psychology from the University of Toronto, and a Master of Science in Public Health (M.S.P.H.) from the School of Public Health, Department of Health Administration, at the University of North Carolina at Chapel Hill. Andre specializes in environmental health, but writes on a variety of issues.