Integrated Pest Management

Integrated Pest Management is a decision-making process for managing pests in an effective, economical and environmentally sound way. An Integrated Pest Management approach can be used for crops and livestock pest management, and in the home garden.

Techniques used in Integrated Pest Management programs range from preventative and cultural measures to the use of biological, physical, behavioral and chemical controls. One or several measures may be coordinated into a management program for a target pest, or for the entire pest complex of insects, mites, diseases and weeds affecting a particular crop.

The Six Elements of Integrated Pest Management

  1. Planning and managing agricultural production systems to prevent insects, plant diseases and weeds from becoming pests
  2. Identifying pests, their natural enemies and damage
  3. Monitoring populations of pests and beneficial organisms, pest damage, and environmental conditions
  4. Making control decisions based on potential damage, cost of control methods, value of production, impact on other pests, beneficial organisms and the environment
  5. Using strategies that may include a combination of behavioural, biological, chemical, cultural and mechanical methods to reduce pest populations to acceptable levels
  6. Evaluating the effects and efficacy of management decisions

The Integrated Pest Management concept has evolved in response to problems caused by over-reliance on chemical pesticides, including:

  • Development of pesticide resistance
  • Elimination of natural enemies of pests
  • Outbreaks of formerly suppressed pests
  • Hazards to non-target species
  • Environmental contamination

Integrated Pest Management requires knowledge of:

  • How to identify pests and evaluate their damage
  • How to identify natural control agents
  • How to select effective control methods that minimize undesirable side effects

Selection of controls for individual pests must be made with the entire crop management system in mind. Many cultural control methods are carried out as part of normal crop production operations.

Integrated Pest Management Example

The following example describes the six components of an Integrated Pest Management program used to manage carpenter ants.

1. Prevention

When pest problems are prevented, pests are not present to do damage, so no control measures are needed.

To prevent carpenter ants from becoming a problem, keep trees, vines and shrubs from touching the house or building. Plants that touch buildings attract ants and can act as “highways” the ants can use to enter the buildings. Fix all water leaks. Store wood in a dry location off the ground and away from the house or building. Carpenter ants seek out moist wood as a place to lay their eggs.

2. Identification

When a potential pest problem arises, the pest must be correctly identified. This is important because most control treatments are specific to particular pests. Once the pest is known, learn about the pest’s behaviour and life cycle. This helps determine when to take action and what techniques to use to reduce the number of pests. For help identifying pests and plant problems, contact a crop advisor, garden center, pest control company, master gardener, or send a sample to the plant diagnostic lab.

Carpenter ants are the most common large ant found indoors in the late winter/early spring. They are 3/5 cm to 2 cm long and predominantly black or sometimes black and red in colour. Winged ants fly in the spring; these are females looking for nesting sites.

3. Monitoring

Always monitor for pest populations, beneficial organisms and environmental conditions that cause problems. Monitoring is important because it provides the information required to make decisions about the timing and location of treatments and whether they are necessary. Monitoring programs include regular inspection for pests or signs of their presence. It is also important to monitor for natural enemies of pests as they can help to suppress pest populations. For some pests, visual inspections (insects, diseases, weeds) and/or counts of insects caught in traps are used to estimate pest populations.

When monitoring for carpenter ants, find out whether or not the ants have a nest indoors. If ants are seen indoors in November through February, there is probably a nest is indoors. From March through October, look outdoors for ants. If they carry food into the house, a nest is inside. Next, determine, as accurately as possible, the locations of nests both indoors and out. Look for areas with a lot of ant activity, areas with moisture, “sawdust” the ants have ejected from their nests, woodpecker holes, and listen for rustling noises the ants make while in their nests.

4. Action Threshold

Determine how much damage is acceptable, and when is the best time to control the pest. This varies with each pest. The action threshold is the level of pest population where control is needed. It will be different for each pest and crop combination. It depends on:

  • What part of the plant is affected
  • The extent of the damage
  • The purpose of the plant in the landscape
  • The cost of the treatments
  • The impact on beneficial organisms
  • The user's tolerance of pests or damage

The user’s tolerance level depends partly on personal taste and perception, including aesthetics. For example, while some homeowners think clover lowers the quality of lawns, others appreciate its drought resistant and nitrogen fixing abilities that contribute to soil fertility.

Carpenter ant action thresholds depend on the species of carpenter ant. Some species rarely, if ever, cause damage, in which case the action threshold will be determined by acceptable nuisance levels. In most cases, plan to begin control when it is certain that a nest is indoors.

5. Management Options

One or several control methods may be coordinated into an Integrated Pest Management program to target a certain pest or several pests. Examples are:

  1. Cultural preventative methods
    Resistant varieties, crop rotation, pruning, plant nutrition and sanitation
  2. Physical and mechanical methods
    Barriers, screens, traps and mulches
    Flame, infrared and hot-water weeders
  3. Biological control agents and beneficial insects
    Predatory and parasitic insects, beneficial nematodes and microbial controls
  4. Pesticides
    Includes synthetic and naturally derived pesticides, insect growth regulators and other products. Where pesticides are used, they should be chosen for compatibility with Integrated Pest Management practices

Treatment options when managing carpenter ants: remove moisture sources; physically remove nests; vacuum ants from nests; treat ant pathways and/or nests with desiccating dust (diatomaceous earth), or slippery barriers, or appropriate insecticides. Managing carpenter ants usually requires the use of a combination of management options.

6. Evaluation

It is important to conduct follow-up monitoring or inspections to find out how successful the Integrated Pest Management program has been. Record what worked and what didn’t, keep the records and review them to help plan pest prevention and management activities.

Evaluate how effective carpenter ant treatments were by looking for ant activity outdoors and in places where nests were found. Inspections are best done in warm weather at various times of day.