The Town of Okotoks is keeping a close eye on the progression of an alien invasive insect pest from Asia, which has already devastated millions of ash trees in Eastern Canada.

Town of Okotoks Urban Forest Specialist Gordon White says the Emerald Ash Borer was likely brought to Canada on shipping containers and so far, the furthest west it's been found is Winnipeg, Manitoba.

He says it's an emerald-green beetle-type insect with a hard shell, about the length of a dime. The Emerald Ash Borer kills ash trees by feeding under the bark and destroying the tree's transport system for sugar and nutrients.  

Early symptoms are yellowing and wilting of leaves and the formation of sprouts on the trunk, while later symptoms can include peeling bark.

"That's usually after the tree has been under attack for several years," White explains. "That's the trouble with this insect, is by the time we know it's in the area it can be very well established. We'll be developing some methods for early detection so we can try and get it before it gets too well established."

He says the town is currently developing an Emerald Ash Borer action plan in case the pest is found here. But in the meantime, there's one way we can all pitch in to try to help stall the pest's progression.

"The biggest message to get out to people at this point is, 'do not transport firewood'," White says. "We're in our camping season and it's jumped several hundred kilometres in Ontario, all the way into Winnipeg, and they suspect that firewood was probably the source of the new infestation."

He recommends purchasing locally-sourced firewood and not transporting it from province to province or even to different areas of the province. Another tip for homeowners is to try to diversify when planting landscapes, as White says incorporating several different species is one of the best defenses for pest and disease control.

The Emerald Ash Borer attacks ash trees such as Manchurian Ash, White Ash, Green Ash and Black Ash. It does not affect Mountain Ash trees, which White says are part of the Rose family.