Before considering pesticides, Integrated Pest Management (IPM) teaches us to identify the pest or disease process before taking the actions of least harm. The IPM website has tools that you can use to identify the pest. The UC Master Gardeners may also help with the determination of the pest or disease process. Understanding the life cycle and activities of the pest will help you to find the correct management solution. Monitor your garden to catch problems early. The next step is to determine if there are preventive or nonchemical methods you can use to reduce the problem. Pest control management may involve one or a combination of methods, including prevention, cultural control, physical control, biological control, or pesticides.
Prevention would include removing the food, water, and shelter the pest uses and blocking access to buildings or plants used by the pest. Cultural control practices alter the environment to make it less suitable for pests to develop and reproduce. Appropriate irrigation, healthy soil, correct exposure to sunlight, and using resistant plants are cultural control actions. Removing debris or infested material will also help.
Physical and mechanical controls block, trap, remove, or sometimes kill a pest. Some examples include knocking pests off plants with a spray of water, using barriers and traps, row covers, cultivating, solarization, or heat treatments. Biological methods use natural enemies or beneficial insects to control pests. Natural enemies may include predators, parasites, parasitoids, or pathogens. Planting nectar producing plants that attract beneficial insects to your garden or yard will help control the pests. Some beneficial insects and their larva look like pests so be sure to identify the “pest” you are concerned about.
As a last resort, pesticides may be necessary when nonchemical controls have proven ineffective, in the event of severe infestation, or if there is a public or structural concern. Once the pest has been accurately identified, use the least toxic pesticides solution. It is of great importance that users read the labels on any pesticide carefully and follow protective safety measures.
According to the new Sustainable Pest Management (SPM) roadmap, the goal of IPM/SPM is to eliminate the use of high-risk pesticides. The roadmap defines “high-risk” pesticides as having active ingredients that are highly hazardous and are likely or known to cause significant or widespread human or ecological impacts from their use. Improper use of pesticides can harm the health of people, pets, and wildlife including pollinators and beneficial insects, waste money without controlling pests, and pollute urban creeks and streams. You can find more information about specific pesticides in the UC IPM Pesticide Active Ingredients Database.
This article was originally published in The Yolo Gardener Newsletter, February 2025
Photo from UC IPM Pesticide Active Ingredients Database