What keeps insects from overrunning the world?

Spring is just around the corner and a new generation of insects will soon be on the wing. A few weeks later, they will multiply and, through the summer, they will produce several generations of descend¬ants. If all these bitsy creatures survived, we would be nudged off our planet. For if all the insects of a single season survived, they would equal the weight of the world,

Here and there a lucky housefly finds a warm crevice and survives the winter. Sometime in April, she lays about 500 eggs. In a short time, her children are ready to produce children of their own, Half of them, being females, can lay 500 eggs apiece. And the first fly, if her children lived, would have 125,000 grandchildren. By summers end she would have billions of descendants   if all the flies survived.

During the summer, insects multiply every few weeks and some produce even larger families than the housefly. Imagine the nightmare if all the crickets, beetles, moths and mosquitoes survived. There would be no room in the world for us. Of course, this nightmare cannot happen because Mother Nature keeps her insect population in balance.

Tons of flies are eaten by frogs, and remember, each fly eaten cannot become the ancestor of billions of other flies. Host of mos¬quitoes are eaten by bats and countless tons of insects are devoured by hungry birds. An anteater gulps thousands of ants or termites at a single meal. The busy mole devours insect grubs in the ground.

Some insects prey on their relatives. The robber fly devours lady beetles. In the water, the larvae of the diving beetle feeds on the larvae of the mayfly. The praying mantis is always waiting to catch a careless cricket for dinner.

All summer long, the balance of nature works to keep down the exploding insect population. A few, just enough, insects from each generation survive and hand on life to a new generation. Billions be¬come food for the countless other animals which enrich our planet. Billions of insects every year perish and decay, adding to the soil the chemicals on which the plant world feeds. This living and dying in vast hordes seems a cruel aspect of the balance of nature. But it is a fact, Without such harsh measures, the insects would overrun the world in a single season.

In recent years, a new factor has been added to the problem of insect population. Han has invented new chemicals to destroy them in vast hordes. Sometimes we use these insecticides too freely, wiping out the good insects with the bad, But, as we learn more about insects and chemicals, we hope to use our pest controls with more control, for if we wipe out all insects, there would be no food for birds, frogs, bats and a host of other charmers.