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How to correctly manage garden pests

October 22, 2011
Dot Zanotti Ingels

A PEST IS anything you don't want around. This includes insects such as aphids, vertebrate pests such as deer and gophers, weeds such as crabgrass and such diseases as mildew and peach curly leaf.

Not everything you may think of as a pest requires control. Some are simply innocuous, and some are even beneficial.

To be able to manage a pest effectively and avoid unneeded action, you need to correctly identify what it is. Control strategies can be ineffective if they are aimed at an improperly identified target or used at the wrong time.

Integrated Pest Management, or IPM, has become the buzz phrase used to explain how to eradicate a pest with minimal toxicity.  Many of us, however, do not fully understand what "pests" we are talking about and how easy it can be to implement an IPM plan in our homes and gardens.

The basic idea behind IPM is to use a carefully planned, ecological strategy to effectively manage pests and keep them from invading your home, damaging your garden or annoying you. The University of California identifies the principal components of an IPM program as:

• Pest identification.
• Methods for detecting, monitoring and
predicting pest outbreaks.
• Knowledge of the biology of pests and their ecological interactions with hosts, natural enemies and competitors.
• Ecologically sound management methods of preventing or controlling pests.

IPM also deals with weeds, and one of the most effective ways to manage weeds is to know the different types and prevent their introduction into your garden.

Once the pest has been identified, its life cycle, seasonal cycle and habits can be learned. This allows more effective use of control methods. Taking a little time to monitor your environment will give you the information you need to make informed decisions about the best, least toxic way to handle a pest you cannot live with.

A proactive IPM approach encourages the use of methods that support long-term prevention or suppression of pest problems with minimum impact on human health, the environment and nontarget organisms. A central concept in IPM is the integration of several control methods such as
resistant varieties, environmental controls, cultural practices, biological
controls and/or the least toxic pesticides for managing your pests.

For example, if you plant a rose variety resistant to disease, give it the right amount of sun, water it properly and keep the area around the plant clean, you often won't need to spray or otherwise treat the plant for mildew or rust. If you garden organically, natural predators like lady bugs will take care of your aphids and bees will not be harmed by pesticide use.

Keeping your garden weeds from going to seed by pulling them early will keep seeds from spreading far and wide, and growing many more weeds that need to be pulled. Pulling a few weeds is easy and reduces the urge to use an herbicide.

Trapping gophers and rats instead of poisoning them protects the owls and other predators that can often take care of the problem for us.

Cultural and environmental controls in the garden include planting the right plant in the right place at the right time, taking care of your soil, using fertilizers, watering properly and keeping the garden clean of debris.

Mechanical controls can be as simple as hand-picking the pest off plants and can include trapping, or mechanical devices like bird netting, or sticky barriers on the trunks of trees.

Biological control methods include conserving beneficial organisms by the judicious use of pesticides.

An IPM program can be carried out in most situations with almost no use of chemical controls. Insecticidal soaps, horticultural oils and certain biologically based insecticides and fungicides may be highly specific and less toxic, but they are pesticides nonetheless.  When IPM is properly implemented, chemical controls are used only as a last resort when nonchemical methods fail to provide adequate control of pests.

If targeted, chemical methods are necessary to control pests, check these resources to make sure that you are using the least risky pest-control method and utilizing it properly (i.e., the right time in the pest's life cycle) to maximize its efficacy:

• UC Pest Notes: University of California's official guidelines for pest-monitoring techniques, pesticide and nonpesticide alternatives for managing pests in homes and landscapes. Some of the subjects covered include: pests of structures, homes, people and pets; insect, mite and
mollusk pests of plants; weeds and unwanted plants; vertebrates and plant
diseases. (www.ipm.ucdavis.edu)

• California Invasive Plant Council: Offers help with weed identification. (www.cal-ipc.org)

• Marin County: Shows how IPM is being used throughout the county. (www.co.marin.ca.us/depts/AG/main/index.cfm)

• Environmental Protection Agency: An array of information about pesticides. (www.epa.gov/pesticides/factsheets/ipm.htm)

Our homes, gardens, neighborhoods, state, country and world are all an integrated ecological web of life. We cannot do anything without affecting something else. A fundamental concept of IPM is that a certain amount of disease or pest damage is tolerable. We need to be willing to sacrifice a few vegetables or cope with a little cosmetic damage so that we can minimize the use of pesticides. As we strike a good balance, many more species will visit our gardens, our homes will be safer and our waters will be cleaner.  We will have started a circle that will spread.

 

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