Chemical insecticides are a useful tool in the control of insect pests but they are not the only method available. The home-owner has a number of biological and cultural options that, from an environmental and health viewpoint, are more attractive. A rigorously followed pest management program around the home and garden will hold pest populations at a level where pesticides will seldom be required and then only as a last resort.

The phrase "pest management" is intended to convey the concept of managing pest populations rather than controlling them. Pest management is a systematic approach to keeping pest populations below the economic/aesthetic injury level. It demands some knowledge of insect life histories and the influence of the physical environment on pest reproduction, survival, and distribution. Much of this information is available from both provincial and federal agriculture departments.

Non-chemical pest control should be used, particularly as the initial step. The following list of common home and garden pests and corresponding control methods could form the basis of your own pest management program.

Garden

Ladybugs and Lacewings prey heavily on aphids; putting these insects on infested plants may be a useful means of control. Remember, insecticides will also eliminate these natural predators. Removing heavily infested twigs is also a quick and easy method of control that usually does no permanent harm to the plant.

Removal of vegetable trash and weeds from the garden in August will reduce the number of cut worms the next year. These worms frequently move from one plant to the next, feeding on the fresh roots. Damage to an entire crop of plants can be reduced by planting shorter rows with worm-resistant plants between rows. Also, coffee tins or plastic pails with the bottoms removed can be used as shields for plant roots. Sink the tin 2/3 of its height into the soil and transplant one seedling into each pot.

Bacillus thuringiensis (variety Kurstaki) is classified as a biological insecticide. Its specific toxicity to caterpillar-type pests, combined with safety to man and the natural enemies of many pests, makes it ideal for use in pest management. Because it is a bacterium and does not spread, it is important to treat the parts of the plant normally attacked by the caterpillars. This product is available on the domestic market under the name Thuricide TM or may be just called a biological insecticide. Alternatively, give your children, or your neighbour's children, butterfly nets and pay them to catch cabbage butterflies before they lay any eggs.

Ladybugs and Lacewings prey heavily on aphids; putting these insects on infested plants may be a useful means of control. Remember, insecticides will also eliminate these natural predators. Removing and destroying all crop debris immediately after harvest will discourage maggot infestations. Spanish onions transplanted after June 10 are less likely to be attacked. Onions are particularly prone to damage when planted close together in rows because the maggots travel from one to another. Planting shorter rows, thinning the rows, and separating them may reduce the damage.

Remove all vegetable trash and other food sources from the garden area and place boards between rows. Destroy the slugs that gather under the boards each morning.

Avoid planting in newly cultivated soil; leave the area dormant for one growing season.

House and Home Gardening Plants

Many insect pests (aphids, white flies, spider mites, etc.) on household plants can be removed by mixing 30 ml of soap flakes into 1 litre of water and heavily spraying the infested plant. This is best done in the bathtub. Separate any infested plant from other plants so insects can't spread. Soil infestations can be controlled by pouring the soap solution into the soil in place of a regular watering. For very resistant insects there are more potent insecticidal soaps on the market.

Use yellow sticky traps to catch incoming winged aphids and screen windows and vents to exclude them. Prune off and discard heavily infested growth, spray remaining plant with soap solution.

This mite thrives in areas of high humidity and moving the infested plants to a dry, cool area should cure the problem.

These gnats like wet soil high in organic matter. Removing rotting leaves and allowing the soil to thoroughly dry between waterings should cure the problem. If not, try soil drenching with a soap solution. Should this not work then wash off the roots and repot in sterilized soil.

Heavily infested foliage should be removed and the plants misted frequently. Remove large mealy bugs before they lay their white fluffy egg masses. Drench the soil with a soap solution, and if the infestation persists, clean the roots and repot in sterilized soil.

Clean the roots and repot in sterilized potting soil. In greenhouses, keep benches and floors clean.

Prune off heavily infested foliage and hand pick large scales. Mist foliage frequently with a soap solution until the problem clears up.

Ornamental Trees and Shrubs

Infested trees showing advanced top and branch kill should be removed and destroyed between late fall and spring. On trees showing early signs of die-back and decline, prune 30-50 cm below all dead branches and tops in late fall and destroy pruned branches.

Control of Dutch Elm Disease (DED) and the elmbark beetle is achieved by a combination of several control methods: removing and destroying diseased, dying or dead trees; keeping elm trees healthy; and chemical control of beetles (usually by municipalities). Most municipalities where DED exists have control teams to identify and eliminate the infected trees.

To prevent reinfection of the tree from pupae overwintering in the fallen leaves and soil, all infested leaves must be promptly raked up in the fall and disposed (burning where possible, or in the garbage). Unfortunately, this won't prevent reinfection from nearby infested trees. Chemical control may be required for severe infestations.

In small woodlots or shelterbelts heavily infested "brood trees" may be removed and destroyed before mid-June. Maintaining a heavy undergrowth of other trees and shrubs seems to reduce risk of borer attacks.

Thorough annual pruning and destroying of galls helps reduce populations. Future plantings should favour the more resistant varieties "Walker", "Dunlop", and "Griffin" over the less resistant "Brooks #5" and "Northwest". Trees provided with adequate moisture, weed control, and fertilization can tolerate infestations of mites and gall development without major detrimental effects.

Cultural control is difficult. Bacillus thuringiensis is effective if sprayed after the new spruce twigs have lost their bud caps and the spruce budworm larvae are half grown. Several sprays may be necessary.

Partial control can be achieved by flushing the foliage with a strong stream of water every two weeks in the summer. Trimming the lower branches to increase light and air circulation will help to decrease mite build-up.

Remove egg bands during early to late spring, or remove young larval colonies after hatching. Bacillus thuringiensis is an effective biological insecticide.

For more information on the proper use of pesticides and alternatives to their use, please see the other fact sheets in this series:

• Alternatives to Pesticides

For further information on pesticides

Call provincial Environment or Agriculture departments or the Agriculture and Agri-Food Canada pesticide information number: 1-800-267-6315.