Practice safe pesticide use this summer
By By Steve Strong / area horticulture extension agent
June 25, 2003
Seems like the entire garden has gone to the bugs already, and the summer growing season has barely begun.
Leaf hoppers, aphids, white flies, thrips, along with stinkbugs, squash vine borers, and all kinds of wormy caterpillars, are attacking your flowers and vegetables. What will get rid of the invading horde?
Choosing the right pest control option is sometimes difficult because what works for one bug may not work for another. The same is true for the vast array of plant diseases appearing on fruit and foliage some may be fungi, bacteria, viruses or none of the above.
The first step in good pest management is to correctly identify the pest, which will narrow the list of control methods to be used. For insects, it is important to decide whether the bug causing the damage has chewing mouth parts or sucking-type mouth parts (tomato hornworms chew, while aphids and stinkbugs really suck).
Certain types of bug killers like carbaryl (found in Sevin) work better on chewing bugs like worms and beetles. Others like malathion or diazinon work on sucking insects like whiteflies and also on the bugs with scraping-type mouths such as leaf hoppers and thrips. Stinkbugs and vine borers may require a pesticide with longer residual control such as endosulfan (found in Thiodan and other brands).
Before buying and using any pesticide, read the label carefully to make sure that the product is safe to use on specific plants, especially those you eat.
Many pesticides are labeled "Do not use on vegetables" and should be applied only to ornamental plants (examples are acephate found in Orthene, and products with "triple action" for disease, insect, and mite control).
All pesticides used on vegetables will contain labels for the number of waiting days until safe harvest. The waiting period may be several days or even weeks depending on the crop and chemical, and it is better to be safe than sorry.
Follow the directions for the correct rates to mix pesticides, and do not be fooled into thinking that more is better.
Many of the fungicides used to manage disease problems can be mixed together with insecticides in the same spray application. Check with the county Extension office at (601) 482-9764 for more information on pesticide combinations for fruit and vegetable pests, and visit Mississippi State online at www.msucares.com.
Both resources also provide gardeners with information on biological and non-chemical pest control, too. One of the safest and most widely used examples is Bt, (short for Bacillus thuringiensis, a naturally occurring bacterium), which acts as a stomach poison only on caterpillars like cabbage worms and corn ear worms. The same stuff is now used in stagnant ponds for control of mosquito larva.
If you do not get the level of pest control you were hoping for this summer, it is possible that you are trying to treat the wrong cause. Disease problems in turf and garden landscapes are often treated as insect problems, and vice-versa. The result is a waste of time and money, and often frustration with the local garden center or product manufacturer.
Pesticides work only as well as the person applying them, and there are plenty of sources for pest diagnosis and control strategies. Your local Extension office offers disease diagnosis through the MSU plant pathology lab for just $6, and nematode analysis for $11 per sample. The pest problem will be addressed at the office if possible for no charge.