Integrated Pest Management - Orange County

What is IPM? 

Integrated Pest Management (IPM) is an ecosystem-based approach that prioritizes long-term pest prevention through methods like biological control, habitat modification, and using resistant plant varieties. Pesticides are used only when necessary, after monitoring determines they are needed, and applications are targeted to minimize risks to humans, beneficial species, and the environment. Effective IPM starts with correct pest identification to ensure management methods are both efficient and safe.

These IPM principles and practices combined to create IPM programs. While each situation is different, six major components are common to all IPM plans:

1. Pest identification
2. Monitoring and assessing pest numbers and damage
3. Guidelines for when management action is needed
4. Preventing pest problems
5. Using a combination of biological, cultural, physical/mechanical and chemical management tools
6. After action is taken, assessing the effect of pest management

Orange County Specialty Pages

What is a pest? 

Pests are organisms that harm plants, structures, or health by causing damage, spreading disease, or becoming nuisances. They can be weeds, animals (like birds or rodents), insects, nematodes, pathogens (such as bacteria or fungi), or any unwanted organism that negatively affects water quality, wildlife, or ecosystems. Information about pest identification and management is available at UC IPM. If you know the name of your pest, use the Pest Notes Library. The University of Georgia’s Center for Invasive Species and Ecosystem Health has a helpful photo collection in their Insect Catalog. 

Exotic and invasive pests also threaten California’s ecosystems, agriculture, structures, and gardens. These organisms are introduced outside their natural range—usually by accident—and may become pests. Some invasive plants originally entered as ornamental species. Prevention is the most cost-effective way to manage invasive species, but when it fails, pesticides may be required for control or eradication. 

Home gardeners can help in this effort by identifying new invasive species in Orange County. 

Consider using native plants for landscaping because they often have fewer pest problems in addition to conserving water and supporting local wildlife. Avoid releasing non-native plants into the environment. Do not discard aquarium plants or water – which can become invasive – into streams or creeks. When traveling, do not bring foreign plants or animals into the state. Buy firewood locally instead of moving it. 

The UC Master Gardener hotline can help you identify pests. Retail nursery and garden centers are among the top sources of pest management information for home gardeners. To help provide customers with the latest pest information from the University of California, the UC Statewide IPM Program created the Retail Nursery and Garden Center IPM News, a three times yearly e-newsletter for retail nursery and garden center employees, managers, owners, and affiliates. 

Report invasive species to your local UC Cooperative Extension office or Agricultural Commissioner, and follow instructions during control efforts.

• Use pesticides only when necessary and combine them with nonchemical methods.
• Select the least toxic, most effective pesticide to protect people and the environment.

Management Strategies

Strategies for managing pests in home gardens are more effective if they are used in combination. They are grouped into the following four categories:

Biological Control: Most gardens contain far more good bugs, or beneficial insects, than pest insects. Beneficial insects and other organisms that kill pests are called natural enemies. The use of natural enemies—predators, parasites, pathogens, and competitors—to control pests and their damage.  In any pest management program, it is important to encourage these natural enemies by avoiding pesticides that kill them. You can also encourage beneficial insects by choosing plants that provide them with pollen, nectar, and shelter and keeping ants out of pest-infested plants. Learn to identify beneficial insects, both in their adult forms and immature (larval) stages.

Cultural Control: By using cultural control, the home gardener can reduce pest establishment, reproduction, dispersal, and survival. These practices – including use of resistant varieties, mulching, weeding, using proper irrigation techniques, and pruning – produce more consistent, long-term pest management. An example: changing irrigation practices, since too much water can increase root disease and weeds. 

Mechanical and Physical Control:  Mechanical controls entail trapping, disrupting pests’ lifecycles by tilling the soil, installing or repairing proper irrigation, destroying weed beds that harbor pests, and eliminating standing water.  An example is using rodent traps. Physical controls involve making the environment unsuitable for the pest’s survival: preventing entry with the use of barriers, manually removing pests by handpicking, vacuuming, or trapping pests. An example is installing row covers for barring insects. Guidelines for using mechanical and physical control: 

• Monitor your garden regularly, walking through at different times of day. Inspect stems, leaves and blossoms. Keep a garden notebook to record pest sightings, noting plant host, numbers, sketch.
• Learn to identify beneficials and pests.
• Keep the garden clean by removing sources of food, water, hiding places for pests.
• Learn to accept some damage in the garden—perfection is not required in the garden; remember, caterpillars become butterflies.
• Prevent infestation by using native plants.
• Fertilize and water appropriately. Over-fertilization may cause excessive growth, weakening of plant and attraction of pests.
• Maintain proper plant spacing to encourage good air circulation.
• Enrich the soil – healthy soil promotes healthy plants. Add compost to the soil to increase fertility and improve soil structure. Use mulch on top of soil to suppress weeds and retain moisture.
• Encourage natural predators by providing food, water, shelter for beneficial insects, birds, and lizards.

Chemical Control:  In IPM, pesticides are applied when necessary and are combined with other methods for long-term pest control. Pesticides are chosen and used in ways that reduce potential risks to humans, non-target species, and the environment. 

• Begin with mechanical controls that are less toxic, such as removing pests with a hose, manually collecting slugs and snails, or using traps and barriers.
• If pesticides are needed, select those that are considered less toxic, including insecticidal soap, horticultural oil, Neem oil, Bacillus thuringiensis (Bt) for caterpillars, pyrethrins, or Spinosad.
• Maintain an inventory of chemical products in your household and update it regularly. Dispose of expired materials and those with unreadable labels or damaged containers appropriately.
• Use pesticides with care and only when other options are insufficient. Follow all label instructions precisely.
• Select pesticides suited to the specific pest and apply them when there is no risk to beneficial insects or mammals. Dispose of pesticides according to recommended guidelines.

Evaluating Outcomes 

Integrated pest management uses scientific methods to manage the whole ecosystem in such a way as to minimize or eliminate pest impact. Regular monitoring and records help assess effectiveness and guide strategy adjustments. Thresholds set criteria for decision-making, while biological, cultural, mechanical, and chemical controls are re-evaluated as needed based on observations and changing conditions.