Tree Damage Identification

Aphids

Aphids, commonly known as plant lice are small, pear-shaped, fragile insects

Apple Maggot

Apple maggot (Rhagoletis pomonella) is a pest fly native to North America, and has been a serious pest of apples in Canada for over 100 years.

Ash Borer

The ash borer or lilac borer (Podosesia syringae) is a day-flying clearwing moth native to North America. The larvae feed on the bark and wood of ash trees and lilacs.

Ash Leaf Cone Roller

The adult of the ash leaf cone roller (Caloptilia fraxinella) is a small gray moth with a 12 mm wingspan. This insect is native to North America.

Birch Leafminers

Three species of sawflies (Fenusa pusilla, Profenusa thomsoni, Heterarthrus nemoratus) introduced from Europe in the early 1970s can be responsible for the premature browning of birch trees

Black Knot

Black knot (Apiosporina morbosa) is a fungal disease that causes greenish brown to black swellings in the stems of cherry trees (Prunus spp.).

Bronze Birch Borer

This beetle (Agrilus anxius), native to North America, is 7-11 mm in length and dark green-bronze in color.

Bronze Leaf Disease

The disease will develop over the summer and infections will spread internally to other parts of the trees. Symptoms typically appear in later summer (early-mid August) or early fall (September) Bronze Leaf Disease

Bruce Spanworm

Bruce Spanworm overwinters as eggs laid singly on twigs. The eggs hatch near the green tip stage of apple.

Cooley Spruce Gall Adelgid

Adelgids are a small group of insects that are closely related to aphids

Cottony Psyllids on Ash

The cottony psyllid (Psyllopsisdiscrepans) belong to the family of insects sometimes called jumping plantlice.

Dothiorella Elm Wilt

Dothiorella elm wilt is a disease involving a fungus (Dothiorella ulmi) that causes the wilting and progressive die-back of American and Siberian elm trees.

Dutch Elm Disease

Dutch Elm Disease (DED) is a deadly disease caused by a fungus (Ophiostoma ulmi) that can affect any elm tree.

Elm Scale

European elm scale (EES) is a pest that normally attacks fruit and ornamental trees.

Forest Tent Caterpillars

The forest tent caterpillar (Malacosoma disstria) is a pest of broad-leaved trees and shrubs. Young caterpillars are black, hairy and about 3 mm long. They cluster together on the trunk or branches when they are not feeding.

Larch Sawfly

The larch sawfly can be detected by looking for the slits on new shoots in which females have deposited their eggs or checking for groups of larvae crawling on the branches

Large Aspen Tortrix

The large aspen tortrix is one of the main insects associated with the trembling aspen. This species occurs throughout the geographic range of the trembling aspen, its preferred host.

Larger Boxelder Leafroller

The larger boxelder leafroller (Archips negundana) is a green caterpillar found on Manitoba maple (boxelder) trees during spring and early summer.

Linden Looper

The linden looper overwinters in the egg stage on host trees. In May, or as soon as the buds begin to open, the larvae emerge and begin feeding on the new foliage.

Mountain Pine Beetle

The mountain pine beetle is a small, black beetle about the size of a grain of rice.

Pine Webworm

Females lay eggs on needles. After hatching, pale green larvae mine the needles. Older larvae live in silk tubes hidden inside a mass built of silk and frass.

Pitch Moth

Pitch moth larval feeding causes infested conifers to produce copious amounts of resin that form globular masses on bark.

Porcupine Damage

Porcupines can cause significant damage to personal and public property by feeding on trees.

Satin Moth

The caterpillars feed principally on the leaves of poplar and willow trees and less commonly on oak

Spruce Beetle

Spruce beetles occur in endemic populations in white spruce stands throughout Alberta.

Spruce Spider Mite

The spruce spider mite (Oligonychus ununguis) is a common pest found on spruce trees. Adult mites are green-brown, have 4 pairs of legs and are scarcely visible to the unaided eye.

Uglynest Caterpillar

The insect is named after its untidy, nest-forming characteristics. Larvae of the ugly nest caterpillar hatch from overwintering eggs in the spring and may be found feeding throughout May to September.

Ungulate Damage

Bucks rub their antlers on small, flexible trees in order to rub off the velvet that initially covers them. During rut, bucks rub their antlers on trees to attract receptive does and to demarcate territory and warn other bucks to stay away.

Western Gall Rust

Infection by western gall rust results in round or pear-shaped galls on branches or stems of susceptible pine hosts.

Yellow-bellied Sapsucker

Yellow-bellied Sapsuckers are fairly small woodpeckers with stout, straight bills.

Yellowheaded Spruce Sawfly

The yellowheaded spruce sawfly (Pikonema alaskensis) is native to North America. Mature larvae are about 20 mm (3/4 of an inch) long. They look like hairless green caterpillars with a series of darker stripes running along the body. They have a distinctive dark yellowish head.

Fall Needle Drop

White Pine Weevil