Best pest control: a gardener's hands

The rain that had kept us indoors for most of the afternoon eased up in time for an after-dinner inspection of the garden. That's when we discovered the slugs, an entire army of the voracious little feeders exposed on the leaves.

Normally slugs feed at night and hide during the day, not because they dislike light, but rather because they cannot tolerate the drying rays of the sun. On this occasion the moist conditions had lured them out early, and getting rid of them was as simple as picking berries. By the time the light faded we had gathered up a cupful of the pests and the garden has been the better for it ever since.

This experience illustrates two basic facts of sensible pest control in the home garden:

* The need to know the habits of the pest in question.

* Handpicking remains a most effective control.

Most insect pests, particularly the flying kind, are vulnerable to handpicking only in the early morning. Not being warmblooded creatures, they get stiff and slow down when temperatures drop at night. Get up early enough, and your defensive forays into the garden will prove most telling on the pest population.

Slugs, too, can be found early in the morning while dew covers the foliage or , it would seem, whenever it is moist enough for their comfort.

Japanese beetles can be picked off readily at any time of day, when you recognize their principal defensive tactic. I was getting nowhere fast one summer evening, picking the beetles off my raspberry patch, when I noticed that, in an effort to escape, the beetles would scramble off the leaf and fall to safety.

Realizing this, I would put one hand under the leaf and wave the other hand over the beetle. The pest promptly tumbled into my cupped hand below.

Remember, insects belong in a garden - both the beneficial ones, from our point of view, and those that insist on a share of the harvest. It's all part of a natural balance. We generally have to resort to more drastic measures only when an imbalance occurs and there is an explosion of a particular pest.

When an imbalance occurs, you will have to take some action to correct it, whether handpicking, as I did with the slugs, or the use of toxic sprays.

But be very careful when you use poisons in the garden - and this applies to organic as well as chemical poisons. They may well be labeled ''relatively nontoxic'' to mammals. But nontoxic does not mean ''harmless.'' Never forget that.