Safe Use of Pesticides

For those who use pesticides, their safe handling should be a paramount concern. Darrell Hensley, Ph.D., an extension specialist with the University of Tennessee Extension explains key areas of pesticide safety.

- Hope Ellis-Ashburn

The best place to start with any recommendations concerning pesticides, including their safe use, is to know the type of pest you are trying to target with their use. If you're unsure, Hensley says that your local extension office is a great place to start as they can help you correctly identify the pest and aid you in selecting the best pesticide to control it.

Pesticides Categories

It's helpful to understand the various types of pesticide categories. The word “pesticide” is a broad term, which may include herbicides, insecticides, fungicides, rodenticides and others. Many of these pesticides are classified as general use and can be purchased without constraint at lawn and garden centers or farm-supply or hardware stores. Others, because of their potential risk to the applicator or the environment, are classified as restricted use pesticides (RUPs), and in Tennessee, where I live, the state requires applicators to be certified pesticide applicators to purchase, apply, mix or transport mixed products.

Pesticides are applied to pests or specific locations and can be further classified into categories such as selective versus nonselective and/or contact versus systemic. Their classification is determined by the action in which they work. Selective pesticides, as their name implies, target a specific type of pest organism, while doing no, to minimal harm to other species. Nonselective pesticides, more commonly known as broad spectrum, are the exact opposite, instead killing a wide variety of organisms to which they are applied.

According to Hensley, contact pesticides burn plants, killing areas the spray contacts. Systemic herbicides travel into the plant when sprayed directly on the foliage and commonly end up in the roots and may kill the entire plant. Some of the systemic insecticides and fungicides that are used work similarly and move throughout the plant to help control insects and diseases.