Oyster shell scale on Cotoneaster
This insect has become a major issue in Calgary over the past number of years. Oystershell scale is hardly recognizable as an insect. On close inspection it looks like a tiny oyster shell. It is one species of a group called armoured scales. Oystershell scale can attack fruit trees, lilacs, ash and elm but in [...]
European Elm Scale has become a large problem in Calgary in the last decade. Symptoms are not obvious unless the infestation level is quite high. Prevention is tough when untreated trees are nearby as the insects move fairly easily between trees. As with most insects and disease, a healthy tree is less likely to be [...]
These microscopic mites feed on the foliar tissue of plants which causes them to form a gall or other deformation on their leaves. They transfer from plant to plant via wind, birds and flying insects. They are generally considered a parasite since they rarely kill plants. Key Points Mainly considered to be an aesthetic issue. [...]
Cottony Ash Psyllid showed up in Calgary about 20-25 years ago. Black Ash and Manchurian Ash are most affected by this insect. Eggs from the previous year hatch in June and nymphs feed until about mid-July. Now adults, they lay eggs in July and early August which hatch and the resulting nymphs begin feeding. When [...]
There are many species of caterpillars that feed on tree leaves. Most are specific about what type of tree they feed on, so an outbreak of caterpillars feeding on an elm will likely not defoliate a nearby Schubert Chokecherry for example. Some species feed on a variety of trees and shrubs, as well as herbaceous [...]
Bronze Birch Borer is another insect that had not been seen commonly in Calgary but has shown up in greater numbers over the past few years due to the added stress that erratic weather has caused the trees in Calgary. The adult female bronze birch borer is an elongate beetle with a metallic greenish black [...]
