Research begins on how to eradicate dangerous giant hogweed
Monday, August 22, 2016, 9:35 AM - Meghan Grguric has spent the summer researching how to control giant hogweed, an invasive and dangerous plant capable of causing serious injuries such as third-degree burns, or in extreme cases, blindness.
The University of Guelph master's student has collected hundreds of bags of giant hogweed to destroy this season, travelling between patches at the university's Woodstock Research Station and other sites throughout southern Ontario. She says there is no real way of eradicating the plant, but several different control methods are being explored.
"Once an invasive species gets in you can't really eradicate it, unless you are tackling it very early at the source," Grguric told The London Free Press.
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The plant has been popping up in large numbers along branches of the Thames River near London, Ont., and across the province with up to 500 known populations. It has also been confirmed in British Columbia, Quebec, New Brunswick, Nova Scotia, Newfoundland and Labrador. It is not present in the territories.
WHY IS GIANT HOGWEED DANGEROUS?
When combined with sunlight, sap from the plants can cause extreme skin irritation, temporary or permanent blindness and scarring. Burns acquired from the plant can continue to cause painful blisters when exposed to sunlight for up to a decade.
Grguric has scars on both her wrist and calf from giant hogweed, despite wearing a protective suit.
Native to southern Russia, the plant first appeared in Canada around 1940. Grguric says it was brought here as an ornamental plant due to its height and impressive look.
The U of G student has seen giant hogweed grow as high as 13 feet. It thrives when located close to water and is known to cause erosion near shorelines. The plant is also believed to have disrupted salmon spawning in British Columbia.
GIANT HOGWEED PRE-BLOOM:
GIANT HOGWEED POST-BLOOM:
Each plant sets thousands of seeds with the ability to remain viable in soil for years.
"Even if it doesn't germinate the next year, it can germinate years after, so you have to keep on top of it," she said in a U of G news release.
Grguric has found herbicides such as Roundup have limited effectiveness against giant hogweed.
"Roundup doesn't control the seedlings that pop up and, in general, doesn't have any soil control, so there is no residual control," she said. "Basically, you spray it, you kill off what's there, and new seedlings pop up a few months later."
Grguric is also investigating injecting herbicides directly into flowering plants. Another control method she is looking into involves pruning and how continuous cutting affects quantity and viability of seeds.
The master's student plans on resuming her research next summer.
Should you come into contact with the plant, it is advised to wash the area thoroughly with soap and water and avoid sunlight for 48 hours. If you think you have been burned by giant hogweed, see a physician immediately.