Integrated pest management (IPM), also called integrated pest control (IPC), combines chemical and non-chemical methods to control pests in a cost-effective way. The United Nations' Food and Agriculture Organization describes IPM as "a thoughtful review of all pest control methods and the careful use of suitable strategies to prevent pests from growing too much and to limit pesticide use to amounts that are affordable and safe for people and the environment." IPM focuses on growing healthy crops while causing the least harm to farming environments and supports natural ways to control pests. Scientists who study insects and ecosystems have recommended IPM since the 1970s. IPM is a safer approach to pest control than using only chemical pesticides. It helps reduce problems such as pests returning after pesticide use, pests becoming resistant to chemicals, and leftover chemicals on food crops.

History

After World War II, when artificial insecticides became available, scientists who study insects in California created the idea of "supervised insect control." Around the same time, scientists in the US Cotton Belt promoted a similar method. In this approach, insect control was guided by trained experts who used information from regular checks of pest and natural enemy populations to decide when to apply insecticides. This replaced methods that followed a fixed schedule. Supervised control relied on understanding insect ecology and predicting how pest and natural enemy populations might change over time.

This idea became the foundation for "integrated control," a concept developed by University of California scientists in the 1950s. Integrated control aimed to find the best combination of chemical and biological methods to manage insect pests. Chemical insecticides were used in ways that caused the least harm to natural enemies. The word "integrated" meant "compatible," showing that chemical and biological methods worked together. Chemical controls were used only when monitoring showed pest numbers had reached a level that needed action (the economic threshold) to prevent losses from becoming greater than the cost of control (the economic injury level).

IPM expanded the idea of integrated control to all types of pests and included more methods. Pesticides were used as in integrated control but had to work well with other strategies for all pest types. Other methods, such as using plants that resist pests and changing farming practices, became part of IPM. IPM brought together scientists who study insects, plant diseases, nematodes, and weeds.

In the United States, IPM became official government policy in February 1972, as directed by President Richard Nixon. In 1979, President Jimmy Carter created an IPM Coordinating Committee to help develop and use IPM practices across government agencies.

Perry Adkisson and Ray F. Smith won the 1997 World Food Prize for promoting the use of IPM.

Principles

An American IPM system is based on six main parts:

• Acceptable pest levels — IPM focuses on keeping pests under control, not completely eliminating them. It is often impossible and costly to remove all pests. IPM programs first set acceptable pest levels, called action thresholds. Controls are used only if these levels are reached. These thresholds depend on the type of pest and the location. For example, a plant like white clover might be allowed in one area but not another. Letting some pests survive at a reasonable level reduces the chance that pests will become resistant to controls. If most pests are killed, the few that survive and are resistant may become the main group in the future. Keeping some non-resistant pests helps reduce the spread of resistance genes. Using the same type of control repeatedly can also increase pest resistance, but switching between different control types helps avoid this.

• Preventive cultural practices — Choosing plant varieties that grow well in local conditions and keeping crops healthy is the first step. Next, practices like plant quarantine and crop sanitation are used. This includes removing sick plants and cleaning tools to stop the spread of disease. Useful fungi and bacteria are added to soil for plants that are prone to root diseases, which reduces the need for chemical fungicides.

• Monitoring — Regular observation is very important. Observation includes checking and identifying pests. Methods like visual checks, insect and spore traps, and other tools are used to track pest levels. Keeping records and knowing pest behavior and life cycles is essential. Insects are cold-blooded, so their development depends on temperature. Scientists use degree-days to model how temperature affects insect life cycles. Degree-days help determine the best time to expect pest outbreaks. Plant diseases also react to weather and seasons in similar ways. Automated systems using artificial intelligence have been created to monitor pests with e-trapping devices.

• Mechanical controls — If pests reach a level that is too high, mechanical methods are used first. These include hand-picking pests, using barriers, traps, vacuuming, and tilling the soil to stop pests from reproducing.

• Biological controls — Natural processes and materials can control pests with little harm to the environment and often at lower cost. The main method is encouraging beneficial insects that eat or parasitize pests. Biological insecticides made from natural sources, such as Bt, fungi, and nematodes, are also used. Other biology-based or ecological methods are being studied.

• Responsible use — Synthetic pesticides are used only when needed and at specific times in a pest’s life cycle. Some newer pesticides come from plants or natural substances, such as nicotine, pyrethrum, and insect juvenile hormone analogs. The active ingredient in these pesticides may be changed to improve their effectiveness or stability. Pesticides must be applied to their intended targets. Matching the application method to the crop, pest, and pesticide is important. For example, using low-volume spray equipment can reduce pesticide use and costs.

Although IPM was first created for farming, it now includes managing diseases, weeds, and other pests in areas like homes, businesses, lawns, and gardens. Predictive models have been shown to be helpful tools for IPM programs.

Applications

Integrated Pest Management (IPM) is used in farming, gardening, forests, homes and buildings, protecting historical and cultural items, and controlling pests in general, including managing pests in structures, lawns, and decorative plants. IPM methods help stop or slow the development of resistance, which is called resistance management.

Process

Integrated Pest Management (IPM) is a method of controlling pests that helps protect crops, public health, and the environment. It uses a combination of actions to reduce harm while keeping costs low. The process begins with monitoring, which includes checking for pests and identifying them. Next, economic injury levels are set. These levels show when pest damage becomes more expensive to fix than the cost of controlling the pest.

Sometimes, action thresholds are used instead of economic injury levels. Action thresholds decide when pest numbers become too high for certain areas, like hospitals or pet kennels. For example, one fly in a hospital operating room is not allowed, but one fly in a pet kennel might be. If pests reach a threshold, steps must be taken to reduce their numbers.

IPM uses many methods, such as cultural controls (like physical barriers), biological controls (like using natural predators), and chemical controls (like pesticides). It works well with organic farming, which avoids synthetic pesticides. Some materials used in organic farming may or may not be approved by the Organic Materials Review Institute (OMRI). While organic pesticides are often safer than synthetic ones, they can still harm the environment. For regular farms, IPM reduces exposure to harmful chemicals and may lower costs.

Risk assessments usually look at four things: the safety of biological controls, health risks, environmental risks, and how well the method works. Mistaking a pest for something else can lead to wrong actions. For example, over-watering might damage plants, but it could look like a fungal infection.

Monitoring starts early, even before pests become a big problem. Farmers check soil and water quality, as plant health depends on pH, minerals, and oxygen levels. Many diseases spread through water used for irrigation.

Once pests are identified, knowing their life cycle helps choose the best time to act. For example, mulch or pre-emergent herbicides can stop weeds from growing. Some crops, like soybeans, may not need action unless pests are very common. If pest damage would cost more than controlling them, action is needed. Health risks might require action even if it’s not economically necessary.

Different areas have different rules. For example, white clover might be okay on the sides of a golf course but not in the fairway. Possible actions include mechanical (like picking pests off plants), cultural (like removing waste), biological (like using natural predators), and chemical controls.

Livestock, such as goats, chickens, and ducks, can help control pests. Chickens in orchards eat insects and weed seeds. Using animals reduces the need for chemicals and provides manure that improves soil.

Biological control methods include adding predators, using sterile insects, or releasing them in large numbers. Augmentative control adds predators regularly. Inundative release uses many predators at once to quickly reduce pests, but it’s not long-term. Inoculative release introduces a small number of predators early in the season, allowing their offspring to control pests over time. Inoculative release is common in orchards and greenhouses. In the U.S. and other Western countries, inundative release is more common, while Asia and Eastern Europe use inoculative methods more often.

The sterile insect technique (SIT) uses sterile male pests to reduce reproduction. However, introducing new species can harm ecosystems. Biological controls are sometimes used to stop invasive pests but may accidentally bring in new pests.

Chemical controls include oils or insecticides. Green pest management uses natural materials, like plant-based pesticides. Pesticides are grouped by how they work. Rotating between different types helps prevent pests from becoming resistant.

Evaluation checks if pest control worked, if it caused problems, and whether the program should continue, change, or stop.

Southeast Asia

The Green Revolution of the 1960s and 1970s introduced stronger plants that could support heavier grain crops due to the use of more fertilizer. Between 1990 and 2010, pesticide imports by 11 Southeast Asian countries increased almost seven times in value, according to FAO statistics, leading to serious problems. Rice farmers began using pesticides regularly after planting, often triggered by signs of the leaf folder moth, which appears early in the growing season. This insect causes only minor damage and does not reduce crop yields. In 1986, Indonesia banned 57 pesticides and stopped providing financial support for their use. However, progress was reversed in the 2000s as production in countries like China increased, lowering prices. Rice production in Asia more than doubled during this time, but farmers came to believe that using more inputs—such as seed, fertilizer, or pesticides—was better.

The brown planthopper, Nilaparvata lugens, the main pest targeted by farmers, has become increasingly resistant to pesticides. Since 2008, outbreaks of this insect have severely damaged rice harvests across Asia, except in the Mekong Delta. There, reduced pesticide use allowed natural predators, such as frogs and wasps, to control planthopper populations in Vietnam. In 2010 and 2011, large planthopper outbreaks affected 400,000 hectares of Thai rice fields, causing losses of about $64 million. The Thai government now promotes a strategy of avoiding pesticide use for the first 40 days of the growing season.

Early pesticide use kills frogs, spiders, wasps, and dragonflies that prey on the planthopper, leading to the development of pesticide-resistant strains. Today, controlling planthoppers requires pesticide doses 500 times greater than originally needed. Overuse of pesticides harms beneficial insects and reduces bird and amphibian populations. Pesticides are suspected of harming human health and have been linked to suicides in rural areas.

In 2001, 950 Vietnamese farmers tested an integrated pest management (IPM) approach. In one plot, farmers used their usual amounts of seed and fertilizer and applied pesticides as they normally would. In a nearby plot, farmers used less seed and fertilizer and avoided pesticides for 40 days after planting. Yields from the experimental plot were as good or better, with lower costs and higher net income. This experiment led to a campaign called "three reductions, three gains," which claimed that reducing seed, fertilizer, and pesticide use could improve crop yield, quality, and income. Posters, leaflets, TV commercials, and a 2004 radio soap opera featuring a rice farmer who adopted these changes helped spread the idea. A 2006 planthopper outbreak harmed farmers who used insecticides more than those who did not. Mekong Delta farmers reduced insecticide use from five times per crop cycle to zero or one time.

The Plant Protection Center and the International Rice Research Institute (IRRI) encourage farmers to grow flowers, okra, and beans along rice paddy borders instead of removing vegetation. These plants attract bees and wasps that eat planthopper eggs, while also providing additional income from vegetable sales.

Agriculture companies often bundle pesticides with seeds and fertilizer, offering discounts for bulk purchases. A proposed law in Vietnam requires pesticide dealers to be licensed and mandates government approval of advertisements to prevent false claims. Insecticides targeting other pests, such as Scirpophaga incertulas (stem borer), the larvae of a moth species that harms rice plants, can increase yields by 21% when used properly.