Small insect causing big concerns in Lethbridge

Concerned citizens packed city council Monday afternoon to hear an update about the European elm scale infestation that is attacking the city’s elm tree population.

Elm trees make up a significant amount of Lethbridge’s urban forest, and of the over 11,000 elm trees in Lethbridge, almost half have been compromised by the insect.

The city is monitoring the situation and trying to control detrimental effects of the insect, but the infestation is causing serious concerns.

“There are 5000 trees, and we have enough chemical today to treat about 600,” City of Lethbridge Parks Manager Dave Ellis said. “That is probably not enough.”

$60,000 has been allocated to the European Elm Scale Injection Program, which is an aggressive treatment program that may take until July to complete.

“We’ve bought extra chemical this year, and we’ll continue as long as the weather allows us to do the injections and do the treatments,” Ellis said.

Although funds and resources have been allocated to fight the pest, the city only has five employees who are licensed apply the insecticide.

“I wish I could say we’re doing more,” Ellis said. “We’re doing as much as we have resources for.”

Tweet This Click to share quote on Twitter: "I wish I could say we're doing more," Ellis said. "We're doing as much as we have resources for."

The unseasonably warm temperatures in southern Alberta are partly to blame for the infestation.

“If we had had a cold rainy summer followed by a really cold winter we would be in a very different situation right now,” Ellis said.

The city is also looking for alternative measures, including pressure washing the insect off the trees and using insecticidal soap.

”We don’t have much information from others that we can draw from,” Ellis said. “Between what we’re doing, and what Calgary is doing, we are kind of making it up as we go.”

The best way to prevent infestation is to keep your elm tree as healthy as possible; this includes watering the base of the tree, and keeping a vigilant eye out for infestation.

Symptoms of infestation include leaf discoloration, premature leaf drop, honeydew secretions on leaves and branches, or black sooty mold growth. If you do see symptoms of infestation in your tree it is best to call a tree care company.