Insects

Ants are not actually a pest of plants. Ants found on plants are generally gathering "honey dew" from aphids. They actually protect aphids from other insects and herd them on the plant to supply the ant colony with food. By eliminating the aphids on the plant, the ants will disappear. Carpenter ants may build nest in old rotting trees but they do not attack live wood. Ants make large colonies in the ground, especially in sandy areas but only create a nuisance.

Aphids are common insects in the garden and exist in many shades of green, brown and black. They are a sucking insect and are found on new growth at the tips of plants. Damage from these insects includes wilting and deformity of new growth.

Aphids are soft shelled and can easily be controlled with insecticidal soaps or insecticides such as Diazinon, Malathion or Carbaryl. They will require several spray applications to eliminate the pest.

Many types of beetles attack plants, usually eating the leaves. Often the eggs are laid on the plant in late fall or early spring. The larvae hatch out and begin eating the leaves. The larvae pupate into a beetle that also eats the leaf of the same plant, later in the season, causing a second round of damage.

Spraying dormant spray early in the spring can help kill off eggs before they hatch. Applications of insecticide early in the season will kill the larvae as they hatch. At the first sign of damage by the beetles, spray the leaves with a residual insecticide, both top and bottom, to reduce further damage.

Diazinon, Malathion, Carbaryl, or Safer's insecticidal soaps can be sprayed directly on the larvae or adult beetles.

Borers are the larvae of beetles. The adult beetle lays eggs on young twigs in the spring. The larva hatch, burrowing into the new soft growth and spend the season in the tree eating soft conductive tissue under the bark. They often work their way down small branches entering the main stem. As they eat the conductive tissue, the sap flow is reduced in the branch, causing wilting of the tips during the summer. The beetle pupates in the trunk and emerges through the bark late in the season leaving a visible hole.

Signs of borer infestation include the wilting and eventual death of upper branches, visible ridges caused by the tunneling insect, and sap escaping from exit holes the following spring.

Control of these insects must be timed to kill the adults in the spring before they lay their eggs. Common sprays include Diazinon, Malathion, Sevin, Lindane and Endosulfane. Borers affect trees in the Prunus (Cherry) and Betula (Birch) families.

Caterpillars are common on many trees and are often present in the spring. They are chewing insects that can completely defoliate a tree.

Spraying at first indication of damage will eliminate them before they do too much damage. Knowing the life cycle of the pest is critical in maximizing the effectiveness of the spray and minimizing the amount of chemical used. An organic spray, often referred to as BTK, contains bacteria that only harms caterpillars. Insecticidal soaps can also be used. To prevent caterpillars from migrating onto the trees, a band of sticky 'Tanglefoot' can be placed around the trunk.

Effective insecticides are Diazinon, Carbaryl, Malathion and Ambush.

For natural biological control consider lacewings, praying mantis and trichogramma wasps.