As more gardeners decide to shy away from pesticides, a greater number of insect traps are beginning to show up on the garden center shelf.
First was the Japanese beetle trap. Gardeners quickly learned that they were very effective in catching the beetles.
But whether the traps are actually effective in controlling the beetles has always been a matter of great debate. Yes, they catch beetles, but do they actually keep them off your roses, raspberries and other garden plants?
To a large degree their effectiveness may depend on how many beetles have invaded your yard. When the number is very high, they can't all get caught in the trap. Some will find their way to the plants, and sprays will be needed.
In most cases, sevin is the product of choice, although gardeners should read the label carefully, especially when fruits and vegetables are involved.
The next trap to hit the shelves was the gypsy moth trap. The effectiveness of this trap is much more in doubt.
The bait in a gypsy moth trap is a pheromone, or sex attractant. It is placed in a station that resembles a hut or strange-looking house. The pheromone is very effective in catching male moths, but only males, because the females do not fly.
If enough traps were positioned around the yard to throughly confuse and disorient the males, it might work. Sooner or later, however, the males are going to find the females, and fertilized eggs will result.
Because the traps are successful in attracting gypsy moth males, they can be used as a tool to see if the moths are in the area and how plentiful they might be.
However, gardeners should not be fooled into thinking that a trap hung in the rear year will rid the area of gypsy moths. A wintertime inspection and counting of egg masses still should be done to estimate populations the following spring. Gypsy moth traps should be hung in July and August.
Other insect traps should be viewed in just this way: They can be a useful tool for estimating insect populations and assisting in accurate timing of sprays.
Many of the other types of insect traps are of the "wing" type. In this design, the inner surface of the bottom is coated with a sticky substance to catch entering insects. A pheromone usually is used for bait. The bottoms can be changed as needed and the lure will last between 30 and 75 days.
Traps should be placed in the area the insect is expected to appear two weeks before its anticipated arrival. Most traps come with instructions.
Traps are available fo codling moth (apple pest), peach tree borer, rhododendron borer, lilac, ash borer, dogwood borer and others.
Traps are available from:
Trece Inc., P.O. Box 5267, 635 S. Sanborn Road, Suite 17, Salinar, Calif. 93915.
Sentry Inc., P.O. Box 426, Buckeye, Ariz. 55326.
Pest Management Supply Co., P.O. Box 938, Amherst, Mass. 01004.
Another interesting insect trap is the yellow jacket trap. This stinging pest often finds its way to picnics, garbage pails or other places where food and sweets are exposed. Once again, whether these traps will eliminate them is questionable. On the other hand, for every one caught, there is one less in the yard.
If you can't find them at your local garden center, they can be ordered from Insects Limited Inc., 10540 Jessup Blvd., Indianapolis, Ind. 46280.
Product controls grasses
Q -- I have about 80 feet of pachysandra that is used as a border. I have never had any grass growing in it before, but this year I am inundated with it and it is growing rapidly and spreading. Is there anything I can purchase to get rid of the grass without harming the pachysandra?
-- R.Z., Cheektowaga
A -- Any broadleaf weeds will have to be hand-pulled, but there is a product that can be used to control grasses in certain ground covers like pachysandra and myrtle.
Fusilade is the active ingredient in Ortho's Grass-B-Gon(cq). It is available in homeowner-size containers at many garden centers. Be sure to follow label instructions.
For answers to your gardening questions, send a self-addressed, stamped envelope to Ken Brown, in care of the Feature Department, Buffalo News, Box 100, Buffalo N.Y. 14240. Brown is a horticultural consultant specializing in integrated pest management.