Rotating Extension Newspaper Column

By: Daniel E. Mullins

Extension Horticulture Agent

Santa Rosa County

Pest Control Recommendations Changing Dramatically

It has become obvious that we cannot, nor should we kill everything in the landscape that bugs us. Pest control is moving from the “shotgun approach” involving blanket sprays of long lasting, broad spectrum products, to more of a “rifle approach.”

Researchers have learned some things over the past 20 years that are changing our attitudes about pest control. Some of these changes have been forced by the recent loss of several commonly used pesticides and because we are learning more environmentally sound practices.

Integrated Pest Management (IPM) is a term that will be heard a lot from Extension Agents in the future. This is a process of managing landscape pests at acceptable levels using all available least toxic methods.

Examples of IPM in the landscape include: choosing plants that are best adapted to the available light and soil moisture condition, watering and fertilizing to encourage acceptable but not excessively lush growth, checking plants weekly in order to detect problems before they become serious and determining if the insects present are harmful or beneficial.

Another important IPM practice involves waiting to see if things will get better without spraying. To do this, it is necessary to establish a threshold for damage. In other words, how much damage can be tolerated before it is necessary to apply a pesticide? In many cases beneficial insects and other organisms increase to a level that can control the pest naturally. Obviously, with food crops and extremely valuable ornamentals, the threshold for damage would be lower.

Every gardener eventually encounters a problem that might require the application of a pesticide. Before a decision is made, the pest should be positively identified. This is important because many of the new pesticides are shorter lived and more specific as to the pest controlled (the shotgun approach).

Several common landscape insect pests can be controlled with 3 relatively non-toxic products and should be included as part of an IPM program. Insecticidal soaps can be used to control aphids, spider mites and other soft bodied insects. Horticultural oils can be used to control scales, mites and certain other species. There is now an ultra-fine oil product that can be used during hot weather. Bacillus thuriengensis or B.t. is a biological control product that can be used to control caterpillars. It is sold under several trade names including Thuricide, Biotrol and Dipel.

New Products Appearing on the Shelf

Anyone who has not shopped for insecticides or fungicides over the past six months is in for a shock. Some of the old standbys are being replaced with new materials with tongue-twisting names.

Some of the new generation insecticidal products contain these active ingredients: Cyfluthrin, Imidacloprid, Pymetrozine, Azadirachtin, Bifenthrin, Lambda – cyhalothrin, Deltamethrin and Permethrin. Most of these are synthetic pyrethroids, so named because scientists learned to produce such compounds that are similar to a botanical insecticide produced by the Pyrethum Daisy.

These products are active in controlling targeted pests. However, it is very important that the pest be properly identified, that it is present in sufficient numbers to require treatment and that the right product be matched up with the particular damaging insect species.

New fungicides are also showing up on the garden center shelf. Propiconazol, Myclobutonil, Azoxystrobin and Thiophanate-methyl are examples of some of the active ingredients. In some cases, these products are more effective than fungicides recommended for disease control in the past. They are however, not cheap.

These new products are available under many trade names offered by several different companies. It will be up to the gardener to read labels closely in order to determine the active ingredient and the intended use.

Extension Service programs are open to all people without regard to race, color, sex, age, handicap or national origin.

Dan Mullins is Extension Horticulture/Vegetable agent for Santa Rosa County.