Okotoks is being infested with a creepy, crawly pest that's killing our Elm Trees.

European Elm Scale has been introduced to North America, and in the past few years has been growing in numbers.

Town of Okotoks Urban Forest Specialist, Gordon White says, European Elm Scale is a scaly bug, that excretes a very sweet 'honeydew' that can cause black city mold to grow very rapidly.

"There's an insect pest called European Elm Scale that has been introduced to North America, and it's starting to increase in numbers to the point where we're starting to see significant branch die back, and health concerns for our Elm Trees."

White says you'll know if your trees are infested because the bark will start to turn black.

"If the tree is starting to turn black, then there is probably enough insects there to see with the naked eye." The bugs are tiny and circular shaped. "The female adult will be a couple millimeters in diameter, and will often have a dark shell with a white halo around them."

Close up of the Elm Scale insect courtesy of Gordon White

White says the town is combating the problem with a class 4 pesticide, which is the least harmful, commercial insecticide.

"We're using a tree injection product called TreeAzin which is derived from Neem Tree seeds." White adds "We're also doing a combination of treatments, as opposed to only using the chemical treatment, we're also spraying the trees down with a strong blast of water to try and physically, knock off some of the insects, as well as cleaning up the bark, and we'll be using a dormant oil, which just coats the insect to prevent them from breathing properly."

If you're worried that your trees might be host to European Elm Scale White says you can try to blast the trees with high pressured water, and keep the bark clean.  If that doesn't work, or if the infestation is too great he recommends calling the professionals.

"If it's a large infestation, or a large tree certainly the best thing to do is hire a trained professional who will have a pesticide applicators license."

Questions, comments, or story ideas? Email us at news@okotoksonline.com

 

 

 

.