This fungal disease affects many Poplar and Aspen species. Both Tower Poplar and Swedish Columnar Aspen are highly susceptible to the disease, which is unfortunate due to the number of these trees in Calgary. Bronze Leaf Disease affects only Poplars but not all poplar species are susceptible. Fungal Spores are transferred by air causing infection [...]
Black Knot Fungus affects Chokecherry and Mayday in Calgary and has been on the upswing the decade. Many trees have been recently removed due to extent of infection. The disease is transmitted through the air which carries the spores to their new host. Pruning to remove the fungus should be conducted when trees are dormant [...]
Photo by: Steven Katovich, Bugwood.org
The larvae of this insect look like a caterpillar. They eat the needles of Spruce causing damage. They have yellowish bodies and yellow/brown heads. The new needles are attacked first. They are chewed down almost to the base before the insect moves on to older needles. A severe infestation, lasting for 3 or more years [...]
In Calgary, young spruce trees are the typical host for the white pine weevil. This weevil is a small brown beetle with a long ‘snout‘. Although the adult beetle is seldom noticed, the effects of the grubs, feeding at the tops of spruce becomes apparent in mid-summer as the leader dies. Key Points Damage usually [...]
Spider mites become active in mid-May and begin feeding on the needles of spruce. These mites are easily moved to other trees by wind or by hitching a ride on the bodies of birds or other animals. Infestations are more likely during dry conditions. There are many generations of mites born each year. Key Points [...]
The poplar bud gall mite is a tiny mite that would never be noticed except for the galls (swellings) it forms on poplar twigs. These tiny mites are eight-legged creatures related to spiders which feed first on leaf buds. While feeding, these mites stimulate the poplar to produce a hard lumpy gall that encases the [...]
