Others regulate the growth of plants or animals. As there are many types of pests, there are many kinds of pesticides. Insecticides control insects, herbicides control weeds, fungicides control fungi, rodenticides control rodents and so on. Pest Control Strategy Proper pesticide selection begins with identifying the pest. Don't panic just because a strange insect is present.
Most insects are harmless and pose no threat.
After the pest is identified, determine if the number of pests or their damage warrants the use of a pest control method. This will vary with the plant species and pest involved. Use a control method only when it will prevent the pest from causing more damage than it is reasonable to accept. For example, yellow nutsedge can be quite disruptive to turf, causing reduced uniformity and density, resulting in decreased aesthetic appeal and ability to prevent soil erosion. If the nutsedge infestation is sufficiently disturbing, identify and evaluate all available control methods.