GENERAL USE INSECTICIDES FOR HOME GARDENING

by Ric Bessin, Extension Entomologist

University of Kentucky Department of Entomology

Home gardeners are confronted with many potential insect problems. The types of problems will depend on their location, the health of their plants, and the types of plants they grow. Depending on the type of plant, problems can range from rare to frequent. A pest management program for home gardeners should rely on proper identification of insect pests, effective use of preventive cultural controls, conservation of natural enemies, and the use of chemical controls as a last resort if other control strategies are ineffective or unavailable for a particular problem.

Cultural controls that help home gardeners reduce pest problems include proper site selection, sanitation of previous crops, weed control, use of resistant varieties, cultivation, crop rotation, altering planting and harvest dates appropriate timing and amount of irrigation and fertilization, and the use of barriers and exclusion. Cultural controls are selected used preventively and selected according to the chances of particular insect problems occurring in the area.

Another important concept is that it often takes a large number of a particular pest to reduce the yield of a plants and affect plant health. A single aphid should not cause alarm, but many colonies on just a few plants may require action. In this instance, a strong stream of water or an application of insecticidal soap may be all that is needed.

This publication lists some of the various general use insecticides that are currently on the market for home gardeners. The usage areas for a particular insecticide are indicated, but you must check each label to be sure that application to particular types of plants are permitted. For example, Lawn and Garden Multi-Insect Killer made by Bayer-Pursell may be applied to some vegetables, but not all types. Only the uses listed on the pesticide label are permitted. You must read the labels to understand the restrictions. Another label restriction is the minimum amount of time between application and when food crops can be harvested. This is referred to as the pre-harvest interval (PHI). Other information concerning mixing and dosages, application methods, protective equipment, and container disposal are also included on the label.

Not all brands of insecticides are listed in these tables, as some companies do not make their pesticide labels available on the internet. But the list does provide a comprehensive guide to the types of materials available to home gardeners. With the ongoing implementation of the Food Quality Protection Act of 1996 (FQPA), we are likely to see changes in the types of materials available. Diazinon, for example, is being phased out and will be off the shelves for home use by 2004.

Understanding the Label

The trade name or brand name is the most prominent lettering on the label. It may or may not contain the name of the active ingredients contained in the container. This can be particularly confusing in the case of Spectracide products because they may have one of several different insecticides as the active ingredient or even a herbicide.

The active ingredient is essentially the generic name of the actual pesticide in the product. This information, along with the amount of actual pesticide in the product, usually can be found in a text box below the brand name.

Company is the manufacturer or distributor of the pesticide. Most companies have an Internet site that will allow you to find more information on their products.

Formulation is active ingredient pesticide plus emulsifiers, inert powders, or clay particles so that the product can be applied in the most efficient or effective manner. Standard abbreviations for them allow you to pick the product that most fits your needs or application equipment.

• EC is an emulsifiable concentrate. It is a liquid formulation that is mixed with water and applied with some sort of pump-up or compressed air sprayer to the soil, turf, or foliage. These formulations can be used for direct contact sprays against sucking insects or as residual sprays against chewing insects.

• F is a flowable formulation. It is a liquid which contains very fine particles of the active ingredient. Flowable formulations are mixed with water for application. The sprayer must be shaken frequently during treatment to keep the small but solid particles from settling to the bottom of the tank.

• L is a liquid formulation. It is mixed with water before application.

• G refers to granule. The pesticide is on or in small particles of a clay carrier. Granules are scattered over the soil or turf for control of pests such as cutworms or white grubs.

• D is a dust. A low concentration of the active ingredient is mixed with a talcum powder like carrier. Dust are applied to plant foliage with a shaker can. They are not mixed with water. Dust formulations are most effective against insects with chewing insects. There is high potential for off-target drift when dusts are applied and is difficult to treat plants evenly or to get good coverage to the under sides of the leaves.

Other Terms

• RTU stands for Ready To Use. These formulations often come in a container with a pump applicator. They are sprayed directly on the site without any dilution.
• PBO is piperonyl butoxide, a synergist that is included in formulations that contain pyrethrins. It increases the effectiveness of the pyrethrins and allows less of that expensive ingredient to be used in a product.
• A systemic insecticide is one that is absorbed through the roots or leaves of the plant. Disulfoton and imidacloprid containing sprays are used as soil applications to control sap feeding insects such as aphids and whiteflies.

ALWAYS READ AND FOLLOW ALL LABEL INSTRUCTIONS

Commercial Web Sites of Garden Insecticide Producers:

CAUTION! Pesticide recommendations in this publication are registered for use in Kentucky, USA ONLY! The use of some products may not be legal in your state or country. Please check with your local county agent or regulatory official before using any pesticide mentioned in this publication.

Of course, ALWAYS READ AND FOLLOW LABEL DIRECTIONS FOR SAFE USE OF ANY PESTICIDE!