Pests cause damage to crops and landscapes. They also can spread diseases to humans through bites and chemicals. Pest control aims to reduce pest populations to an acceptable threshold without harming other organisms. Control methods include prevention, suppression, and eradication.
Biological control relies on a pest’s natural enemies (predators, parasitoids, pathogens) to limit its population. These natural enemies must be imported carefully to minimize risks to non-target organisms.
Biological Control
Biocontrol involves the use of living organisms to control pests sustainably. This mode of pest management seeks to avoid negative impacts on the crop and other ecosystem components and may eliminate or reduce reliance on synthetic chemical pesticides.
Biological control methods include preventing or stopping a pest from becoming established, suppressing a pest population to an acceptable level, and eradicating a pest. Prevention is usually the goal, but it is only possible in outdoor pest situations if reasonably predicted.
Augmentation is a crucial component of most biological control programs and can take the form of mass production and periodic releases (inoculative or inundative) or genetic enhancement of natural enemies. The most commonly augmented natural enemy is the minute endoparasitoids known as Trichogramma wasps, which are now used worldwide in agricultural and forest systems. Other types of augmentation are also available, but they need to be carefully planned and executed to be effective.
Chemical Control
Chemical controls are a part of the modern Citrus County pest control arsenal. These include insecticides (killing agents) and other substances, such as fungicides and nematodes that can kill or debilitate insects. It is the most commonly used chemical, a bacterium that produces toxins to kill caterpillars and other lepidopterans. Several other nontoxic, pest-specific formulations can be used as well.
Overuse of any pesticide can result in the rapid development of resistant organisms. In addition, many pesticides are detrimental to non-target organisms such as birds, earthworms, and pollinators. Integrated Pest Management (IPM) is an approach to pest control that considers all of the above. Pest densities, natural enemies, weeds, weather, and other factors are considered before using pest control tactics. This allows a certain level of pest activity to be tolerated without negatively impacting crop production. Predators, parasitoids, and pathogens are all used to suppress pest populations to less damaging levels.
Physical Control
In this form of pest control, a person or machine physically removes pests from plants and structures. This includes trapping and using mechanical and chemical means to remove rodents in living or work spaces and remove weeds by hand pulling or hoeing.
Pesticides are liquid, powder, or gaseous substances that destroy or disrupt the growth or activity of a pest. Sanitation practices prevent and suppress some pests by improving cleanliness and reducing the available food, water, or shelter. Environmental features such as mountains and large bodies of water restrict the movement of many pests.
IPM aims to manage pests through prevention, suppression, or eradication, with as little harm as possible caused to other organisms. This is accomplished by scouting and monitoring to determine the type and number of pests.
Cultural Control
Pest control techniques that reduce pest numbers or damage to an acceptable level without chemical materials are considered cultural controls. They manipulate the environment to make the crop and surrounding habitat less attractive or unsuitable for pests, interfere with their feeding, oviposition, or dispersal, or promote the presence of natural enemies or limiting factors in the pest population.
These include intercropping, the use of trap crops (such as strips of alfalfa planted in cotton fields to attract lygus bugs), crop rotation, and planting hedgerows that contain pollen-producing plants, nectar plants, or host alternatives for natural enemies. Plants and microorganisms that produce semiochemicals can also be used as biological control agents, releasing these chemicals to deter or inhibit pests.
Careful planning is needed for acquiring and releasing biocontrol agents. Release guidelines depend on the biology of the pest and its natural enemy and how their interactions affect each other. Suppression of pests should not be confused with eradication, as there is often a lag between a pest population increase and the build-up of natural enemies.