Introduction to Integrated Pest Management (IPM)
Ever since the dawn of humanity, people have been dealing with pests in various ways. A pest is defined as an organism, usually an insect or pathogen, which has characteristics that are regarded by humans as injurious or unwanted. Our capability to reduce pest populations increased dramatically since World War II with the advent of inexpensive, effective synthetic pesticides. Pest control strategy quickly became a regime of toxic chemical applications on crops, livestock, and in homes, schools, and businesses. While initially effective, people soon discovered that pests can become chemically resistant after repeated exposure to the same (or similar) pesticides. It was also realized that these plentiful toxins were causing health problems in people and were producing negative effects in our precious natural environment.
Over time, more responsible pest control techniques were developed, including an effective and environmentally sensitive approach we now call Integrated Pest Management (IPM). This approach to pest control can be used in virtually all settings where pests are encountered, and aims to use the least harmful methods that will still yield satisfactory control. Pesticide applications may be used, but only as a last resort. The least toxic chemicals will be chosen for use, and will be applied at the lowest concentration (rate) and frequency that will provide effective control.
IPM utilizes many different strategies to discourage and prevent plant damage caused by pests. In practicing IPM, growers set action thresholds, monitor and identify pests, prevent outbreaks, and ultimately reduce the overall use of pesticides. IPM programs define thresholds by assuming that a low level of pests is tolerable. Using four simple approaches, IPM practitioners can prevent or control pest damage while using the most environmentally sensitive approach.
This step is one of the most important components of an IPM program. Pest control is unnecessary if pests can be excluded or discouraged. Hygiene can be an important factor, such as keeping greenhouse and plant growing areas clean, and eliminating weeds and plant debris. Healthy plants can resist pests and diseases better than weak plants, so it is critical to understand the individual cultural requirements of your plants. Methods such as repotting on time, reduction of overhead watering, proper plant placement, and not over- or under-watering will help to reduce plant stress. These control methods can be very effective and cost-efficient and present little to no risk to people or the environment.
The second step is to monitor and scout weekly. Locating and identifying problem areas and accurately identifying pests and their lifecycles will ensure that appropriate control decisions can be made. Not all insects, weeds, and other living organisms require control.
Before taking any pest control actions, step three is to set action thresholds. Sighting a single pest does not always mean control is needed. Determining a level at which damage is unacceptable is a vital part of an IPM program.
Once monitoring, identification, and action thresholds indicate that pest control is required, and preventive methods are no longer effective or available, step four is to evaluate the proper control method both for effectiveness and risk. Less toxic pest controls are chosen first, including pheromones or insect growth regulators (IGR) to disrupt pest mating and pest maturity, or mechanical control, such as trapping, water-blasting or weeding. If further monitoring, identifications and action thresholds indicate that less risky controls are not working, then more potent pest control is needed.
After the initial chemical application or control action is done, revisiting the site to determine the effectiveness of the control or action will determine further steps.