Pest Management Basics

Pests are unwanted organisms (insects, fungi, nematodes, weeds, or vertebrates) that damage plants and/or property. Pests may be continuous or sporadic.

Effective pest management requires careful monitoring and evaluation. It relies on long-term prevention techniques including biological control, habitat manipulation, change of cultural practices, and use of resistant plant varieties. When pesticides are used, they are selected and applied according to established guidelines. Contact Armis Pest Management now!

When pest populations reach unacceptable levels, IPM programs use a combination of strategies to manage them. These include physical, cultural, biological, and chemical controls. The University of California Statewide IPM Program defines IPM as “an ecosystem-based strategy that focuses on long-term prevention of pests or their damage through a combination of techniques such as biological control, habitat manipulation, modification of cultural practices, and use of resistant varieties.”

A key component of IPM is monitoring pests to determine the type and severity of the problem. This involves regular scouting to accurately identify the pest and its population level. It also includes assessing and considering economic or aesthetic injury thresholds (the point at which action should be taken). Once the pests have been identified, treatment options can be selected from a set of preventive or curative management tactics. Chemical treatments are only used if all other prevention and control tactics have been exhausted.

Preventive IPM measures prioritize hindering pests from entering or establishing themselves in an area. This can be done by denying them the food, shelter, or proper temperature they require to survive and thrive. This can be achieved by removing weeds, mulching, preventing the growth of desirable plants, avoiding excessive watering, and implementing soil rotation and other methods.

Biological IPM measures utilize predators and parasitoids to keep pests at bay without the need for chemicals. This can be a highly effective and sustainable option, but it requires a significant investment of time to find a suitable source for the predator or parasite, understand how and when to release them, and learn which pests they target. Once implemented, an IPM plan must be reevaluated regularly to ensure success.


Whether you are managing a garden, farm or forest, monitoring is the first step in determining what pests are present and how much damage they have caused. It also helps to determine if you need to take action at all. If the problem is limited to one or two plants, you may only need to treat them. In other cases, you might need to manage the entire ecosystem.

Regular inspections of your garden, farm or woods allows you to catch a pest infestation before it gets out of hand and prevents the need for costly treatments. If you use traps or sticky traps to monitor pests, it can help you get ahead of the curve and catch them when their populations are still low.

For example, if you are trying to control the scale insect in your trees, catching them when their numbers are low can help reduce or even eliminate their need for pesticides. Similarly, if you are trying to monitor the lilac borers, trapping them early in their life cycle before they become serious can significantly reduce the need for control.

Another benefit of monitoring is gaining information about the presence and activity of natural enemies of pests. If the population of a specific pest is declining, it is often a good indication that it is being attacked by its natural enemies. Natural enemies that are being killed by pesticides can often be restored through targeted releases of predators or parasitoids.

It is important to evaluate the results of any pest management program against its desired outcomes. If the results are not what was expected, then the program might need to be changed or eliminated altogether.


Prevention is an important step in a pest management program. It can help reduce the need for toxic chemical products and ensure technicians are using environmentally conscious practices. In addition, preventive strategies can be more cost-effective in the long run. Preventive actions can include sealing entry points, regularly inspecting a property, and providing proper waste disposal. Proper sanitation is also important to reduce the spread of pests, particularly in urban settings. Regularly cleaning and disinfecting food preparation areas can help prevent the transfer of pests from one plant to another or from a person to a food source.

Many natural forces influence pest populations. Climate, for example, affects the growth of plants and the pests that feed on them. It can also affect their ability to reproduce. Other natural factors that affect pests include predatory organisms, parasitoids, and disease pathogens. Predators and parasitoids can greatly reduce pest numbers by eating them or destroying them from the inside. Disease pathogens can cause the death of a pest species or make it unfavorable for other organisms to host them.

Often, these natural enemies are more effective at controlling pests than are chemical methods, and they are generally safer for the environment and human beings. Sanitation can reduce the spread of pests as well by removing their food, water, and shelter sources. This can be done by improving trash handling, reducing pest harborage, and decontaminating equipment and tools before and after use. Mechanical controls such as knocking pests off of plants with a spray of water or putting them into traps can also be used to prevent their propagation.

Nonchemical methods are often the first step in preventing pest invasions and should be employed before any chemicals are used. Some nonchemical methods are cultural, involving modifying the site to make it less attractive or desirable to pests; others are physical such as spraying plants with water, growing competitive plants, and removing shelter or food sources.


Pests are kept in check in well-balanced ecosystems by their natural enemies (409). These organisms—predators, parasitoids, diseases, and herbivores—can reduce or eliminate pest populations. Unfortunately, most conventional pesticides kill these organisms along with the pests they target. Therefore, it is important to conserve and encourage these beneficial organisms when possible.

Prevention tactics include planting insectary flowers to attract predators and parasitoids; avoiding crop rotations that can expose plants to disease; and using mulch to prevent weed germination. Physical barriers like netting or screening can help discourage insect pests from entering greenhouses or other structures. Irrigation scheduling can also be used to avoid conditions favorable to disease development. NRCS works with farmers to coordinate conservation plans with Integrated Pest Management plans.

When prevention tactics are not sufficient, suppression techniques can be employed to keep pest populations at tolerable levels. This involves monitoring pest populations and assessing damage, then applying appropriate control measures to minimize or eliminate the pest population.

Suppression tactics can include reducing the number of eggs or seeds produced by the pest, increasing the rate of natural enemy-induced mortality or sterility, or applying a targeted genetic modification to the pest itself. Because most natural pest populations are regulated by density-dependence, a moderate reduction in their reproductive capacity is usually enough to cause the population to decline to a lower equilibrium level.

Biological control, also known as augmentation or classical biological control, is the introduction of natural enemies from other locations to prevent pests in crops. Examples of this approach are nematodes that suppress harmful soil grubs, and the pheromone-releasing wasp Encarsia formosa that controls greenhouse whitefly. These natural enemies are often expensive to purchase and require specialized warehousing and handling procedures.


The goal of eradication is to remove a pest population from an area entirely. Eradication is a rare goal in outdoor situations where prevention and suppression are usually the goals, but it is a common goal in enclosed spaces such as homes, schools, hospitals, office buildings, and food processing plants.

The word eradication has several meanings, depending on context: it can mean to exterminate or uproot (literally or metaphorically) an undesirable plant or animal species. It can also refer to the elimination of a disease or an infectious agent. Two diseases that have been eradicated are smallpox and rinderpest. The eradication of both of these diseases was made possible by vaccination campaigns that succeeded in eliminating the corresponding pathogens.

To achieve eradication, pesticide use should be reduced to the minimum level necessary for pest control, applied in an environmentally sound manner, and used under conditions that minimize disruption of natural enemies. This may be done by rotating crops and chemical types, using resistant varieties, reducing the amount of water used to produce a crop, avoiding the use of fertilizers that can increase pest problems, manipulating mating or host-finding behavior with pheromones or other synthetic compounds, and using physical controls such as traps, weed barriers, steam sterilization of soil, or insect screens.

Eradication is often difficult to achieve, particularly when a pest has been introduced into an environment that does not have naturally occurring predators or parasitoids to keep the population in check. Many pests, such as gypsy moths and Japanese beetles, can not be managed with biological control methods because they do not have natural predators to maintain populations in balance with the plants they attack.