Integrated Pest Management

What is Integrated Pest Management?

Integrated pest management (IPM) is the combination of cultural, mechanical, biological, and chemical tools to prevent, manage, and control pests (fig.1). Pests can be weeds, insects and other invertebrates, bacteria and other microorganisms, viruses, and in some cases vertebrates, such as mice in a grain elevator. 

The steps to implement an IPM program are:

  1. Prevention 
  2. Monitoring 
  3. Decision making, i.e. thresholds, critical periods, disease models 
  4. Implementation of solution 
  5. Monitoring to asses effectiveness of solution implemented

Cultural practices are typically used in the prevention of pests, while chemical, biological, and mechanical tend to be used in the management and control of pests.



Fig. 1 Components of Integrated Pest Management

Controlling a pest in a crop does not mean complete eradication of the pest. Pest control is bringing the pest population numbers to levels where the losses in quality and/or quantity due to the pest presence are below economic injury levels. In other words, it is not advisable to take action if the solution is more expensive than the damage expected by the pest (fig. 2). Action should be taken at critical periods, action thresholds, or when a disease is forecasted, depending on the nature of pest. 
IPM plans provide crop protection while reducing human and environmental health risks associated with the use of pest control products. The central components of all IPM plans are both prevention and monitoring, with constant record keeping throughout. 


Image caption: 
Fig. 2 Pest numbers by time

Fig 2 . Pest numbers are represented by the continuous red curve. Action threshold [AT (ET)] and Economic Injury Level (EIL) are represented by the dashed green and blue lines, respectively. These are the pest levels at which action to control should be taken. If no action is taken, pest levels could surpass the economic injury level, represented by the dashed red line. At this point, the producer is losing more money by the damage incurred by the pest than the money it costs to implement a solution

What are the benefits of Integrated Pest Management?

Integrated Pest Management is a holistic approach that diversifies the tools used for protecting crops against pests. In this way, the onset of pesticide resistance can be delayed and the efficacy of pest control products is prolonged. Future generations of farmers will have efficacious options to combat the pressures of the future. 
IPM can result in economic gains by reducing the total inputs required to provide crop protection. When IPM strategies are implemented, meaning that action is taken only when it’s needed, as opposed to a scheduled program, there may be a reduction in the number of sprays required. The result is a reduced input cost to the producer.
Environmentally, IPM may reduce environmental risk through the same mechanism by which it conveys potential economic benefits. If fewer inputs are required there is less exposure of pest control products to the environment and to the organisms that interact with the agro-system, including humans.

How to Develop an Integrated Pest Management program?

  1. Prevention
    Become familiar with your crop, the pests associated with the crop, and potential management and control options in case they are needed. Key concepts to consider: 
    1. Know and recognize the development stage of your crop
    2. Recognize the organisms that jeopardize the crop and learn to differentiate them from those that are beneficial, such as pollinators and predators of pests (hover flies, endemic bees and wasps, ground beetles, spiders, lacewings, endemic ladybeetles, etc.)
    3. Use reputable sources of information such as fact sheets published by recognized institutions and/or organizations, i.e. universities, governments, grower associations, research institutes
    4. Proceed with caution when assessing information from online forums, or when using information from reputable sources that are located in jurisdictions with different conditions from yours. The action thresholds for pests are not set in stone. These are flexible, varying depending on the interaction between the host, the pest, and the environment. The closer to you the information came from, the higher the chance that the system will behave similarly 
    5. Once you are familiar with the stage at which pests pose a challenge, for example critical periods for weed control, learn to monitor for it 


  2. Monitoring
    Record when you see pests. Going by memory is not a valid way of monitoring. Monitoring is conducted by scouting, placing traps and/or lures, or by forecasting. Forecasting is done using models that vary in complexity, some of which use accumulation of degree days and others use multiple factors such as relative humidity, air temperature, and presence of inoculum. It is important that the monitoring technique used has been validated, so that the thresholds correspond to an actual economic value, i.e. what does it mean to have 1 aphid/plant, is there a risk? Keep in mind:
    1. Usually, this information is recorded on data sheets, where numbers of pests can be tallied and compared to thresholds. 


  3. Decision making
    You should be familiar with thresholds, critical periods, and models to forecast diseases before you start monitoring for them. This is part of the prevention step #1. In this step is when you ask: Are there any biological control agents I can use?  Are there enough predators in my system that I can expect the problem to be taken care of? Which of the pest control products available suits my needs best? If there is more than one pest control product, do they have the same mode of action? Make sure you rotate mode of action to deter pesticide resistance. 


  4. Implement solution
    Follow the label of all pest control products used; respect the rates approved for its use, the number of applications per season allowed, pre-harvest and reentry intervals. It is the law and any violation is a violation of the Federal Pest Control Products Act. 

    Make sure that if you use pest control products, you or the applicator has a valid pesticide applicator certificate issued by the Department of Environment, Water and Climate Change. It is the law. Any violation is a violation of the Provincial Pesticides Control Act. 

    The use of Invertebrate Biological Control Agents is regulated under the Plan Protection Act¸ enforced by the Canadian Food Inspection Agency. Make sure that the products you use are allowed and have the appropriate permits. 


  5. Monitoring to asses effectiveness of solution implemented
    The last step and it will allow you to assess risks such as development of resistance, calibration issues, or perhaps plan for cultural practices next season such as site selection and/or changing varieties.

Additional Information on Integrated Pest Management:

The information contained in the links below is for general reference only. They are included with the intention of starting a discussion about developing Integrated Pest Management strategy. Some may not be applicable to you and some may require further refinement depending on the interaction between the environment, the pest, and the host; there is no silver bullet when working with pests and what works in one farm may not work in another.

Who to Talk to about Integrated Pest Management?

Agri-Environmental Specialist/Provincial Minor Use Coordinator 
Eileen Beaton
PEI Department of Agriculture
P.O. Box 2000, Charlottetown PE
C1A 7N8
Tel: 314-0388
Fax: 368- 4857


Manager, Sustainable Agriculture Resource Section
PEI Department of Agriculture
P.O. Box 2000, Charlottetown PE
C1A 7N8
Tel: 368-6366
Fax: 368-4857

Published date: 
May 8, 2023

General Inquiries

Department of Agriculture
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P.O. Box 2000,
Charlottetown, PEI C1A 7N8

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Fax: 902-368-4857

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