Birch Leaf Miner can be prevented for the summer season with a systemic insecticide be placed in the soil at the drip line of the tree as the tree is leafing out. It will move up to the leaves and kill insects that between the leaf layers. Do not apply to young or newly planted trees. It does not need to be done every year. Birch Leaf Miner cannot be controlled by contact insecticides.

Lilac leaf miner can be controlled by painting each branch of the shrub between the leaf layers, during that summer. It should be applied to a different area of the bark each year, and should not be done every year. Lilac leaf miner cannot be controlled by contact insecticides.

Poplar leaf miners do little harm other than to appearance. There is no chemical control, as the ends of roots are impossible to find (for soil drench) and the bark too thick for painting. They can do considerable damage but do not endanger the tree.

The larvae are tan with two rows of black spots and black heads. They skeletonize leaves of poplar trees, so only the large veins are left.

Cottonwood Leaf Beetles can be controlled with a contact insecticide sprayed on the tree when the insects are present. They can do considerable damage but do not endanger the tree.

They suck the sap from the leaves, leaving them mottled with white spots. By late summer the leaves become brown and crisp.

Leafhoppers can be controlled with contact insecticides sprayed on the insects. The insects are often on the undersides of vine leaves, and many vines are against walls and fences, preventing the chemical from reaching them. If a garden hose can be aimed into the foliage it can dislodge many of them.

They are usually seen on sunny fences or walls of buildings. They are attracted to box elder (Manitoba maple) trees. The small red insects are juvenile.

Box Elder bugs do little harm and can be safely ignored. A strong stream of water from a garden hose can discourage them.

They pierce the leaf tissue and suck liquid from the cells of the leaf, leaving yellow stippling on the upper side and brown spots of excrement on the underside.

Ash plant bugs may be sprayed with a contact insecticide if seen early enough to prevent damage but are not usually noticed until it is obvious. Damage done is not serious.

Some feed on birch, willow, ash and oak foliage. Others are sucking insects that feed on tomatoes. They all have sturdy bodies with angular shoulders and obvious antennae.

Stink bugs can be controlled with contact insecticides if in large numbers. Use one that is appropriate for the plants affected.

The larvae pierce the leaf and suck fluids from it, causing light flecks on the upper side of the leaf. The dark, sticky excrement on the underside of the leaf can be enough to stop the leaves from manufacturing food.

Lace bugs can be controlled with contact insecticides if in large numbers. Use one that is appropriate for the plants affected.

The damage they do is minimal compared to that of their larva. White grubs (the larval stage) spend up to three years in the soil, eating the roots of lawns and root vegetables, particularly potatoes.

Do not plant potatoes in an area infected by June bugs. There is no chemical control for potatoes, but lawns can be treated with soil or liquid insecticides appropriate for lawns.

The female also covers her eggs with froth. Adults resemble brown leafhoppers and are not covered with spittle. Both nymphs and adults pierce foliage and twigs to feed on sap.

Spittlebugs can be controlled with contact insecticides appropriate to the plants affected. Damage is unsightly and occasionally enough to harm the plant.

The adults feed on flower buds. It punctures them and the holes are obvious as the flowers open. They also feed on the tips of new rose shoots, causing them to die. The larvae feed on the reproductive parts of the flowers.

Rose Curculio dusts and sprays are available to control Rose Curculios as they occur.

They can be found on the stems, flower buds or new leaves and can attack almost any plant by sucking sap from the tissue. Leaves often curl over and are stunted, and a sticky residue called honeydew can be a nuisance. Ants are often seen in these areas as they like the sweet honeydew.

Aphids can be controlled with contact insecticides but they will kill only those insects they touch. The insects are often inside a rolled up leaf and contact is unpredictable. There are many generations, so it is impossible to eliminate them all. A frequent, hard spray of water will keep them somewhat under control.

Leaves curl and become very unsightly but little damage is done to the tree. Later in the summer they migrate to saskatoon, their alternate host. They live in the roots and can damage young seedlings.

Wooly Elm Aphids are difficult to kill with chemicals as the aphids are curled up inside the leaves and are not reached by contact insecticides. Dusts may be used in the soil of saskatoons if aphids are present, but be sure they are safe for food plants.

They leave a purplish lumpy look to cranberry leaves. The insects underneath the leaves do relatively little damage.

Aphids on Cranberry can be hosed off with a strong spray of water. Contact sprays suitable for fruiting plants can be used.

Aphids on Honeysuckle Shrubs cannot be controlled with chemical sprays, as the spray cannot contact the insects inside the folded leaves. Pruning the tips whenever aphids are seen, and removing them from the garden, is the only control.

They suck sap from the new wood that is easy to penetrate, and will cause small branch ends to die but do no major harm to mature trees.

Aphids on young trees should be sprayed with a contact insecticide when they are present. It may have to be repeated if more are seen later. Mature trees will not be harmed by the loss of twigs on the ends of the branches.

They do, of course, indicate that aphids are or have been present, but nothing need be done unless actively feeding insects are seen.

Aphid skins need no control unless live aphids are also present.

They are long and narrow and leave speckles on the leaves, which die prematurely. Thrips can be controlled with contact insecticides when insects are present.

There are two generations per year. Willow Sawfly Larvae can be picked off or controlled by contact insecticides when present if in large numbers.

The young larvae eat the tissue between the veins of leaves close to the ends of branches. Older larvae eat all but the largest mid-vein. Nematus Sawfly Larvae can be controlled by contact insecticides if present in large numbers.

They feed on leaf tissue, leaving dry areas between the veins. They are common on Purple Leaf Plum and Cotoneaster. They are most active in the fall, so plant growth is not affected. Pear Slugs can be controlled with contact insecticides if numbers are excessive.

They eat leaves of Elm, Willow, and Aspen and can defoliate smaller trees. They are the larvae of the mourning cloak butterfly. Caterpillars that are exposed can be killed with contact insecticides, but those rolled inside leaves will not be affected if the spray cannot come in contact with them.

As feeding continues, the holes gradually enlarge until only leaf veins are intact. Trees produce another set of leaves a few weeks later, but severe infestations can weaken a tree. The caterpillars drop on silken threads to move to new areas. They move with a looping motion. Mature larvae of Spring Cankerworms overwinter in the soil and pupate in the very early spring, emerging soon to begin feeding. Fall Cankerworm eggs overwinter on trees and hatch in late May to begin feeding.

Cankerworms that are exposed can be killed with contact insecticides, but those rolled inside leaves will not be affected if the spray cannot come in contact with them. A biological insecticide controls them when they are young and feeding.

It does not do enough damage to cause concern. The adult is a gray moth. Red-cheeked loopers can be controlled by a contact insecticide when they are present, if damage is enough to warrant it.

It defoliates willow and poplar, but causes little damage. The adult is a small grayish-yellow moth. Hydria Undulata can be controlled by a contact insecticide when it is present, if damage is enough to warrant it.

It feeds on birch and Willow leaves, but does minimal damage. The adult is dull, gray-brown moth. Lithophane Amanda can be controlled by a contact insecticide when it is present, if damage is enough to warrant it.

The adult is a tan tussock moth. The larvae eat leaves of Willow, Manitoba Maple, Birch and Aspen, but cause little damage. Wooly Bear Caterpillars can be controlled by a contact insecticide when it is present, if damage is enough to warrant it.

The head is blue-green and there is a pale yellow line along the side of the body. They defoliate Birch, Bur Oak and Willow. Giant Silkworms can be controlled by a contact insecticide when they are present, if damage is enough to warrant it.

They are caused by minute mites which trigger gall growth in the tree. A gall is the tree's way of protecting itself from an invader. Ends of branches beyond galls may die because the gall can constrict a branch and water cannot move along the branch. Poplar Bud Gall mite cannot be controlled with a chemical. Pruning off the growths is the only control.

Swellings on the ends of native willows look like pine cones. A gall is the tree's way of protecting itself from an invader. Ends of branches beyond galls may die because the gall can constrict a branch and water cannot move alongthe branch. Willow Pinecone Gall cannot be controlled with a chemical. Pruning off the growths is the only control.

A gall is the tree's way of protecting itself from an invader. Ends of branches beyond galls may die because the gall can constrict a branch and water cannot move along the branch. Rose Gall cannot be controlled with a chemical. Prune the canes down to well below the gall and remove from the garden.

Chokecherry Midge cannot be controlled with a chemical, as the insect is inside the fruit and any chemical affecting it would be eaten by those that eat the fruit (animals and birds as well as people).

They are caused by a sawfly which inserts the eggs into the fleshy layers of the leaves. Willow redgall does no harm to trees other than appearance. They are unsightly but cause no damage. There is no chemical control.

Eriophyid mite galls are unsightly but cause no damage. There is no chemical control.

The swellings look like strings of beads at the edges of the leaves of balsam poplar. Parathecabius Galls cause the leaves to be deformed but there is no danger to the tree. There is no chemical control.

Box Elder (Manitoba Maple) Leafgall causes the leaves to be deformed but there is no danger to the tree. There is no chemical control.

Crawlers emerge, and move to leaves for a short time in the summer. They spend the rest of their lives immobile on twigs. Oystershell Scale cannot be controlled with chemicals. Cutting off affected branches can be effective if infestation is light, but if they are on many branches or return after several prunings, removing the tree or shrub may be the only effective control.

Scale is a hard covering over the eggs of an insect which protects the eggs until they hatch. Crawlers emerge, and move to leaves for a short time in the summer. They spend the rest of their lives immobile on twigs.

Lecanium Scale cannot be controlled with chemicals. Cutting off affected branches can be effective if infestation is light, but if they are on many branches or return after several prunings, removing the tree or shrub may be the only effective control.

Scale is a hard covering over the eggs of an insect which protects the eggs until they hatch. Crawlers emerge, and move to leaves for a short time in the summer. They spend the rest of their lives immobile on twigs.

Scurfy Scale cannot be controlled with chemicals. Cutting off affected branches can be effective if infestation is light, but if they are on many branches or return after several prunings, removing the tree or shrub may be the only effective control.

Cottony Scale cannot be controlled with chemicals. Cutting off affected branches can be effective if infestation is light, but if they are on many branches or return after several prunings, removing the tree or shrub may be the only effective control.

The creamy white larvae excavate tunnels beneath the bark, producing a series of bumps. The adults chew D-shaped holes through the bark. Upper branches of trees die as the tops are affected the most. This insect is not commonly the cause of tree top death in our area. Lack of water in the fall is a much more common reason for the top of the tree not leafing out in the spring.

Bronze Birch Borer cannot be controlled by a chemical. Pruning the top back to healthy growth is the only control.

Trees under stress are most likely to be affected. Leaves on an affected tree branch will wilt suddenly and later die. A ring of small holes like a bracelet around the branch indicates beetle infection. There is no chemical control for Western Ash Bark Beetle. Infected branches should be removed as soon as seen and sealed in a plastic bag before discarding.

They feed on poplar foliage, and then cut crescent-shaped notches in the bark where they deposit eggs. The larvae are creamy white grubs that bore into the heart of the tree, ejecting sawdust as it occurs. Trees infested with poplar borers exude large amounts of brown sap. This does not kill the tree but it weakens it so it can break during windstorms. Woodpeckers are attracted to the tree in search of insects, and ants are attracted to the sap.

There is no chemical control for Poplar Borer. Affected branches should be removed. Areas where sap is flowing can be cleaned out and left open to heal.

They cause galls (swellings) on the tips of spruce tree branches that resemble small green pineapples at first, then become hard and brown.

Branch tips with missing needles are unsightly and new needles will not replace those that are lost. Yellow-headed Spruce Sawfly Larvae can be controlled with a contact insecticide only when they are present. It may have to be repeated if more are seen later.

The masses of frass and debris they produce in the center of the tree are unsightly. Web Spinning Sawfly webs and dead needles can be removed by a hard stream of a garden hose. By the time the damage is noticed the insects are usually gone. They cannot be controlled by a chemical unless it can be sprayed on the larvae.

Nesting Pine Sawfly webs and dead needles can be removed by a hard stream of a garden hose. By the time the damage is noticed the insects are usually gone. They cannot be controlled by a chemical unless it can be sprayed on the larvae.

She inserts eggs into the elongating shoots of larch trees in early June, causing them to curl downwards. The developing larvae eat the needles. Larch Sawfly larvae cannot be controlled by a chemical because it cannot come in contact with them inside the branches.

The larvae are greyish green with dark spots and reddish brown heads. Resin flow occurs from active galls as the larvae tunnel in below the bark, producing resin masses. The tunnelling often causes breakage of branches.

Pine Pitch Moth galls should be pruned back to the next branch below the gall. The branch beyond the gall will die because water cannot get past the gall, and will usually break off in a strong wind.

It attacks dead and dying spruce, pine, douglas fir and larch. It feeds on bark and foliage, then lays eggs in cracks in the bark. The greyish-white larvae enter the sapwood of the tree and tunnel further into the tree for two years. Chips and frass are expelled through holes in the bark.

White Spotted Sawyer attacks only dead or dying trees and does no damage to living trees. No control is necessary.

The leader curls over and the needles die by late summer. Small exit holes can be seen where adult weevils have emerged. White Pine Weevil cannot be controlled by a chemical. If the leader is pruned back to just above a healthy branch, it can be bent up and tied to a stick to form a new leader.

They are small, either white or red, and form fine webs between the needles or between small branches. They can infest junipers and spruce. Spider Mites are not insects, but members of the spider family. Frequent hosing the tree with a hard spray of a garden hose can keep them under control. If chemical control is desired, use a mite killer, not an insecticide.

They are rather large, black aphids, on the bark on the interior of the plant, so often unnoticed until needles become brown. They should be eliminated, as they can do considerable damage.

Aphids can be controlled with a contact insecticide sprayed well into the tree. Check the trees regularly for more aphids and spray as needed to eliminate them.

t attacks pine trees particularly. Eventually the tree becomes less healthy as needles discolor and drop.

Pine Needle Scale cannot be controlled by insecticides. The chemical cannot reach the insect underneath the scale. The tree can survive for may years with scale but there is a danger of it spreading to neighbouring trees. A badly infected tree may have to be removed.

Keep the soil free of any mulch and dead plant material, and water in the morning, to allow the soil to dry before nightfall, as they cannot move easily over dry soil. They cannot move across sand or diatomaceous earth, so a band of either will keep them away from particular plants. If slug bait is used, be sure it is covered well to prevent dogs and cats from eating it. Do not use near edible plants.

They cause galls (swellings) on the tips of spruce tree branches that resemble small green pineapples at first, then become hard and brown.