16 July 2015
by Amy-Jean Maclean
It’s green, it’s yellow, it’s leafy all over, and it won’t go away.
Leafy spurge is an invasive species that was accidentally introduced to Manitoba about 200 years ago. It’s still a problem in a lot of areas today because it has no natural predators, so it will grow rampantly. When it gets into pastures, most livestock won’t eat it, and while the natural foliage is consumed, the leafy spurge continues to grow.
The RM of Stanley, however, seems to have found a way to curb the spurge through biological control. They’ve introduced a foreign species, the aphthona flea beetle, which eats the weed.
“Our method is trying to control it using natural methods,” says Richard Warkentin from the Stanley Soil Management Association. “You don’t eliminate [the weed] because you’re using these beetles, which is a living organism you’re using to control another living organism, so what you get is kind of a balance.”
Warkentin says they introduced the beetles to the municipality over the last 20 years, and they’ve seen great results. He says usually they saw an 85 to 90 per cent decrease in leafy spurge stems in a 20 square meter area over five years.
This isn’t necessarily unique to the RM of Stanley. Warkentin says other areas of Manitoba have reined in their weed woes through the use of the flea beetles, but he says that Stanley is probably is one of the municipal frontrunners for effectively using the little bugs.
“A lot of places, they just release the beetles, and maybe take a picture and don’t really have information as to how effective they are,” he says, “and we actually have been collecting data. We have 18 sites that we monitor every year, and so we actually have good information, and our information shows, that on average when we have the beetles, well, we’ve had up to a 100 per cent control [of leafy spurge].”
Warkentin says it’s also important to prevent the spread of leafy spurge. He recommends to avoid harvesting forage crops with leafy spurge in them, and to check vehicles for leafy spurge.