Using the wrong pesticide can do more harm than good

Misusing a garden pesticide could rid your garden of more than just pests. If you don't carefully follow the directions, you could harm yourself, the environment or end up with results much different than you had expected.

By law, each pesticide container is required to tell the user what the product is used for, the target pest, location of the target pest, application rates, protective clothing needed, precautionary measures, and other application information to increase effectiveness of the pesticide. All of this information is extremely important to follow.

Be sure to identify the pest causing your problem before you make any pesticide applications. Homeowners often tell me that when they see a problem with one of their plants, they automatically apply sevin just in case it will correct the problem. But using the wrong pesticide can actually do more harm than good.

For example, the cause of a plant problem can be an aphid. If sevin is applied, it will not control the aphid. Sevin must be ingested to kill insects. Aphids just sweep sevin aside with their hypodermic needle-like mouth parts, and suck juices out of the plant. Sevin can kill predator insects feeding on aphids, and therefore cause an actual increase in the aphid population.

It is common to hear pesticide users say if a little does some good, a lot should do a lot of good. This is not always the case. For example, use of glyphosate at above normal rates often causes foliage burn. When the foliage is burned, introduction of the herbicide into plant tissue is difficult, and the herbicide does not kill target weeds properly.

Often it is a common practice to keep mixed pesticide in an applicator container until it is needed in a week or two. This practice quite often negates the effectiveness of the pesticide. Studies have shown that under some conditions, pesticides lose their effectiveness within a few minutes to a few hours after mixing with water. Mix up only the amount of pesticide that you are going to use for each application.

It is important to read the label in order to determine if watering or sunlight is required for activation. For example, use of granular trimec requires that foliage be wet when application occurs. In addition, rain within 24 hours after application often negates the effectiveness. Use of glyphosate requires at least 4 to 6 hours of sunlight after application in order for herbicide to be effective.

Be sure you know where you can use a particular pesticide. Diazanon can be used on home lawns, but not on golf courses or cemeteries. Some pesticide containers say that diazanon can be used on vegetables, while others do not.

Almost all pesticide containers say keep out of reach of children and pets. Don't get overly alarmed, but always be careful. These are the same precautionary statements on many household cleaners.

Remember to use pesticides effectively and carefully, it is extremely important to follow label directions.

Send your gardening and landscape questions to Paul Schnare at P.O. Box 699; Cape Girardeau, Mo. 63702-0699 or by e-mail to news@semissourian.com.