⏳ Estimated Reading Time: 9 - 11 minutes

Describe integrated pest management (IPM) and the benefits and drawbacks of IPM.

Integrated Pest Management

The diagram illustrates the link between interventions, toxicity levels, and prevention. Arrows on the left represent Intervention and Prevention, while the right arrow symbolizes Toxicity. In the center, a pyramid divides interventions into CHEMICAL (high toxicity) at the top and CULTURAL (low toxicity) at the bottom. — **IPM is not a single strategy; it is a combination of several control strategies.**

Integrated pest management (IPM) tries to control pest populations by using all suitable methods – cultural, mechanical, biological, and chemical – to bring about long-term management of pest populations with minimal environmental impact. IPM does not seek to completely eradicate pests, but control them, keeping crop damage caused by pests below 10%.

Prevention of pest infestations is of utmost importance when employing IPM. Pest populations can be kept at minimum levels by making sure that plants are healthy enough to ward off pests and making sure that there are few places for pests to hide and reproduce. When prevention appears to not be doing its job, we move towards intervention or taking steps to address the growing pest population. Interventions can be cultural, physical-mechanical, biological, or chemical. Chemical pesticides can be a part of IPM, but the overall goal is to use as few chemicals as possible to control and manage the pest population.

IPM is a management strategy rather than an elimination strategy.

Click through the tabs below to learn about each step in the Integrated Pest Management (IPM) process.

Cultural
Physical/Mechanical
Biological
Chemical

Cultural Pest Control

Cultural control of pests is when we alter one or more of the environmental factors using non-chemical methods. This is our first line of defense against pests when using IPM.

Open each tab below to learn about some types of cultural pest control:

Crop rotation is a type of cultural control that involves the systematic planting of different crops in a specific sequence over time. This practice disrupts the life cycle of pests by depriving them of their preferred host plants. Crop rotation also improves soil fertility and suppresses insects and diseases, which can enhance the crop’s ability to compete with weeds.

♻️ Crop Rotation (click to reveal)

Sanitation is a type of cultural pest control that involves removing or destroying sources of pest habitat or food, such as crop residue, spilled seed, weeds, or volunteer plants. Sanitation can reduce or eliminate pest populations that depend on these resources for survival or reproduction, and also prevent the spread of pests to other areas. This method can help avoid or minimize the need for pesticides or other control methods, and also improve the overall health and productivity of the crop.

🗑️ Sanitation (click to reveal)

- - - Conventional tillage can expose or kill underground pests, such as larvae, pupae, or eggs, and also destroy their food sources or habitats.
    - Reduced tillage involves less intensive soil disturbance than conventional tillage, such as chiseling, subsoiling, or strip-tilling. This type of tillage can reduce some of the negative effects of conventional tillage, while still providing some pest control benefits.
    - No-till or zero-till involves planting the crop directly into the undisturbed soil, without any prior tillage. This type of tillage can conserve soil and water, improve soil structure and fertility, and enhance natural enemies. However, it may also favor some pests that thrive in undisturbed soil or crop residue, such as slugs, cutworms, or wireworms.

🚜 Tillage (click to reveal)

Mulching is a type of cultural pest control that involves covering the soil surface around plants with a layer of organic or inorganic material. Mulching can help prevent or reduce pest problems by:

- - - Suppressing weed growth, which often harbor harmful insects
    - Creating a physical barrier, preventing certain pests from reaching the plant roots or laying eggs in the soil
    - Modifying the soil temperature and moisture, which can affect the activity and survival of some pests
    - Enhancing the activity and diversity of natural enemies, such as predators and parasites, that can control pests

🍂 Mulching (click to reveal)

Mulching can also improve the overall health and productivity of the soil and plants, making them more resilient against pests.

Intercropping is a method of growing two or more crops simultaneously on the same field.

The most common goal of intercropping is to produce a greater yield on a given piece of land by making use of resources or ecological processes that would otherwise not be utilized by a single crop.

Intercropping can have various benefits, such as improving soil and plant health, reducing pest and disease incidence, enhancing biodiversity, and increasing income and food security.

🌾 Intercropping (click to reveal)

Allelopathy is a biological phenomenon by which an organism produces one or more biochemicals that influence the germination, growth, survival, and reproduction of other organisms.

These biochemicals are known as allelochemicals and can have beneficial (positive allelopathy) or detrimental (negative allelopathy) effects on the target organisms and the community.

🧪 Allelopathy (click to reveal)

Planting time is a type of cultural pest control that involves adjusting the timing of planting or harvesting to avoid the peak activity of pests. By anticipating insect problems before they occur, the control techniques avoid or minimize the pest’s impact on the crop. Planting earlier than normal may also give the crop a competitive edge over pests.

📆 Planting Time (click to reveal)

Resistant varieties are a type of cultural control that involves choosing plant varieties that have natural or bred resistance to certain pests. This means that the plants can tolerate or prevent the infection or damage caused by the pests, reducing the need for pesticides or other control methods. Resistant varieties can be developed by conventional breeding, genetic engineering, or gene editing techniques.

🐛 Resistant Varieties (click to reveal)

Physical/Mechanical Pest Control

Two goats amidst greenery. One is perched on a tree branch, while the other stands on the ground looking up. — **Some farmers and ranchers bring in herds of goats to remove problem plants. The goats will remove a target pest plant then the area can be grazed or planted with crops later.**

Physical and/or mechanical control of pests are both effective methods of reducing pest damage. Whether it is simply removing pests from a tomato plant by hand or wrapping netting around a fruit tree, the goal is to make it difficult for the target pest to access the fruit, vegetables, or crops being grown.

Examples of Physical/Mechanical Pest Control:

mosquito nets 🦟
cages around trees or plants to keep out pests 🌳
picking weeds 🌿
cultivating the soil with a hoe or tractor 🚜
mechanical removal of weeds by goats or other animals 🐐

Biological Control

A photo of ladybugs on yellow flowers. — **Ladybugs have a voracious appetite for aphids, a common pest that causes problems in gardens.**

Biological control involves the use of certain organisms by humans to eliminate or control pests. In this type of control, natural enemies are identified and brought in to prey on the target pest. In general, pests have four types of natural enemies that can control pest populations:

predators 🐞
parasitoids 🦟
pathogens (diseases) 🦠
in the case of weeds, plant-eaters 🐛

The problem with controlling a pest by using its natural enemies is finding organisms that provide control of the target species WITHOUT attacking other, desirable species. The first step in this process is protecting natural enemies that already exist in the area. If the natural enemy is not already present, it can be sometimes purchased and released into the garden or crop to be protected. For example, ladybugs and praying mantises can be ordered online and released into the target area.

Ladybugs have a voracious appetite for aphids, a common pest that causes problems in gardens. Praying mantises are effective predators of many different insect species.

One obvious problem is trying to encourage the natural enemies to stay where they are released. Hopefully, they will significantly reduce the target pest species before they move on!

Bacillus thuringiensis (Bt) isn’t a predator of pests, but it is a type of bacteria found naturally in soil.

Bt can be concentrated and used as a spray on insects. When the insect ingests the bacteria, the proteins in the bacteria kill the pest but these proteins cannot be activated by mammals so species higher up the food chain are not impacted.

Chemical Pest Control

The guide outlines efficient scouting of a large green crop field with clear, numbered steps. It advises starting at a distance from the field edge, separating stops, limiting area coverage, and alternating patterns for thorough observation. — **Tips for scouting fields for pests.**

If ecological control methods are not enough, IPM does allow for the use of chemical pesticides as a last resort to control pests.

Instead of spraying on a specific schedule, farmers will scout their fields and determine whether they need to spray or not.

If monitoring of pests indicates that action is needed, IPM utilizes cultural, physical/mechanical, or biological controls initially. If these controls are not working, chemical pesticides are used. In IPM, chemical pesticides are not used indiscriminately, but they are used only when necessary and effective.

Essential Knowledge

Integrated pest management (IPM) is a combination of methods used to effectively control pest species while minimizing the disruption to the environment. These methods include biological, physical, and limited chemical methods such as biocontrol, intercropping, crop rotation, and natural predators of the pests.

Benefits and Drawbacks

In summary, integrated pest management is a management strategy for controlling pests and involves a series of informed decisions about the timing and type of control method needed to keep pests at an acceptable level.

Prevention is the foundation of IPM, and chemical pesticides are only used if other control methods are not effective. The goal of IPM is not only to control pests but also to safeguard the health of humans, other species, and ecosystems.

All of the non-chemical methods of pest control are effective when done correctly and under the right circumstances. Chemical control may have to be considered should any of the other methods not do the job against the pest. The goal today is to minimize chemical use whenever and wherever possible to avoid bioaccumulation and biomagnification. This helps protect the ecosystem and our own health.

Essential Knowledge

The use of integrated pest management (IPM) reduces the risk that pesticides pose to wildlife, water supplies, and human health.

IPM does less damage to the ecosystem, soil, water, and air, but it is not without drawbacks. IPM has three main drawbacks:

Open each tab below to see how natural disasters can affect the human population:

📈 More Technical and Complex (click to reveal)

IPM requires more participation and knowledge from the farmers or pest managers, as they have to monitor the pest population, identify the pest species, evaluate the damage threshold, and select the most appropriate control methods.

IPM may take longer to achieve the desired results, as it relies on preventive and biological measures rather than quick chemical solutions. IPM also requires more labor and resources to implement the various control methods, such as habitat manipulation, biological control, and cultural practices.

⏳ More Time and Labor Intensive (click to reveal)

IPM may not be able to completely eliminate the pest problem, as it aims to reduce the pest population to a tolerable level rather than eradicate it. IPM may also face challenges from environmental factors, such as weather, climate change, and pest resistance, that could affect the effectiveness of the control methods.

⚠️ More Risk and Uncertainty (click to reveal)

Essential Knowledge

Integrated pest management (IPM) minimizes disruptions to the environment and threats to human health but can be complex and expensive.

AP Exam Tip

You should understand how integrated pest management works.

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