Biological control of insects.

Abstract

One commonly hears allusion made to the phenomenon known as the “ Balance of nature”, the principle on which arc based all attempts at biological control, that is, the control of one species of living thing by another. The phrase “ Balance of nature ” describes the state of equilibrium which occurs in any given locality between the native species of plants and animals. Any one species is prevented from multiplying to such an extent that it, will jeopardize the welfare of the others, and each component of the native fauna and flora takes its part in confining the other components to a limited sphere. The principle is well illustrated by the predatory animals which keep down the numbers of other wild life.