What is it? Woolly elm aphids is an tiny insects that require two hosts (American elm & Saskatoon) to complete their life cycle. The insects alternate between two hosts and cause damage by sucking sap from them. Symptoms Damages What to do? Other resource: https://agriculture.canada.ca/en/agricultural-production/crop-protection/diseases-and-pests-agroforestry/woolly-elm-aphid
Category: Tree Pests
European Elm Scale
What is it? European elm scale (EES) is a small soft scale that attacks elm trees, by sucking sap from branches and leaves. They hatch in late July and start feeding in mid-July, then overwinter on branches and twigs. Symptoms Damages What to do? Other resource: https://www.calgary.ca/parks/pests/elm-scale.html
Birch Leafminer
What is it? Birch leafminers are several species of sawflies that attack all species of birch trees. The larvae feeds between the surfaces of a leaf, causing mostly aesthetic problem to the tree. Symptoms Damages What to do? Other resources: https://tidcf.nrcan.gc.ca/en/insects/factsheet/7765 https://natural-resources.canada.ca/forest-forestry/insects-disturbances/birch-leafminer
Dutch Elm Disease (DED)
What it is? Dutch Elm Disease (DED) is a devastating disease that affects all elm species. It is caused by a fungus primarily spread by three species of elm bark beetles. The disease obstructs the tree’s ability to transport water, ultimately leading to its death. Alberta was free from Dutch Elm Disease for the past […]
Forest Tent Caterpillars
What is it? Forest tent caterpillars (Malacosoma disstria) is a pest of broadleaved trees and shrubs. They can completely defoliate a tree and cause tree health decline. Symptoms Damage What to do? Other resources: https://tidcf.nrcan.gc.ca/en/insects/factsheet/9374 https://gardening.usask.ca/articles-and-lists/articles-insects/article-forest-tent-caterpillar.php
Cotton Ash Psyllid
What is it? Cotton ash psyllid is an invasive pest to Calgary that attacks black ash and Manchurian ash trees. They like to attack trees that are already stressed. Symptoms Damage What to do? Other resources: https://www.calgary.ca/parks/pests/cottony-ash-psyllid.html https://gardening.usask.ca/articles-and-lists/articles-insects/cottony-ash-psyllid.php
Bronze Birch Borer
What is it? Bronze birch borer is known as metallic wood-boring beetle that feeds on birch tree. It usually attacks birch trees that are already stressed. It can kill a birch tree within a few years. Damages What to do? Other resources: https://tidcf.nrcan.gc.ca/en/insects/factsheet/283
Eriophyid Mites
What is it? Eriophyid mites are many different types of translucent, microscopic mites that cause deformities in many plant species. They feed on cells under the plant surface and causes abnormalities of plant tissues such as witches’ brooms, curled leaves, galls, yellowed leaves. They also serve as an alternative food source for predatory mites, which […]
Ash Leaf Roller
What is it? Ash Leaf Roller is a moth that affects ash trees. As the caterpillar grows, it rolls the leaf into a cone shape, where the larvae continue to grow until they reach the pupal stage. The adult moths emerge from the leaf cones, typically starting around mid-July. Damage What to do? Other resources: […]
Western Ash Bark Beetle
What is it? Western ash bark beetles are small, oval shape, 2-3mm long and brown in color. They attack ash trees by tunneling between the bark and wood, causing branches to die. They usually attack dead and injured branches, and trees stressed by other factors, such as drought or incorrect pruning. Symptoms Damages What to […]