Intergrated Pest Management (IPM) is a decision-process that uses all available pest management strategies to prevent economically damaging pest outbreaks while reducing risks to human health and the enviroment. IPM is a continuum along which there are many levels of adoption. It can range from simple monitoring to properly time pesticide use all the way to "biointensive" IPM in which there is a total elimination of synthetic pesticides as in organic farming.
In a IPM program, treatments are not made without first monitoring the situation and evaluating whether a pest is likley to be a problem. In schools, there are three injury levels used to determine when to implement pest management strategies:
Economic Injury Levels determine the level of damage to a structure or plant. Once damage has reached a level that is severe enough to cause economic loss, control should be implemented. An example would be a termite infestation that requires replacement of some structure.
Aesthetic Injury Levels, on the other hand, are the levels at which a pest becomes a nuisance for whatever reason. Perhaps this is the level at which an aphid population drops enough honeydew onto a picnic table beneath a shade tree to disturb the people using the table. Aesthetic injury levels are subjective, that is, what is tolerated by one person may not be tolerated by another.
Medical Injury Levels are used whenever a pest can cause illness to humans either directly or in directly. Rodent-transmitted diseases would be one example.
IPM requires continuous assessment of a situation. There are four key questions that must be answered before implementing any management strategy.
Is treatment necessary? The mere presence of a pest doesn't necessarily warrant treatment. Sometimes a fairly large population of pests can be tolerated while other times the presence of a single pest is tolerable. In addition , the determination of treatment will vary among individuals.
Where should the treatment take place? Pest managers must look at the whole system to determine the best place to solve the problem. Apply treatments where the actions will have the greatest effect. In order to do this you must completely understand the biology and behavior of the pest at hand.
When should action be taken? Timing is very important. There are optimum times in both insect and disease life cycles when they are most susceptible to control. Again, it is very important to understand the biology and behavior or your pest.
Which strategies should be used? IPM uses a multi-tactic approach. Because biological systems are complex, management strategies must also integrate several strategies. Rarely will a single tactic solve the problem for long. Implementing an IPM program means taking a "whole system" or ecosystem approach to solve a pest problem. You must think of both the living and non-living components when determining which approach to take. Each component has an impact on every other component.
There are four control strategies that are used in developing an IPM program.