MANKIND'S SMALLEST FRIEND.

Dunstan Times, Issue 3131, 21 August 1922, Page 2

MANKIND'S SMALLEST FRIEND.

(By a Naturalist). "Ladybird, ladybird. fly I away homo," sing the village school children, but unfortunately the little red beetle with black spots on his coat of mail docs not listen to them. For if it were not for the ladybird the green fly would play havoc in our gardens. v There is a strange instructive knowledge in the insect world. When the ladybird is about to lay her flusters of yellow, cone-shaped eggs, she seeks a plant that the green fly infest. So soon as the etig is hatched the grub starts out to devour the aphides and eats them until, being full grown, it reaches the pupa stage. This lasts some days, and then the skin splits and the ladybird emerges, and she, too, turns to the green fly or aphis and eats incessantly. She raises several families, or rather lays eggs several times, her responsibility ending when they are laid in the proper position, and the last broods are: ins hibernating ones. They get under the bark or trees in little companies, and pass the winter in a state of suspended animation. One of the most remarkable sides Nature's economy is seen in the relations between the ladybird and the green aphis. The former keeps the latter under control, and as each ladybird as larva and beetle must devour many hundreds of aphides, it might lie thought that the latter would become extinct. But if they did the ladybird would go short of food and so there a balance is preserved. In some years the ladybird dominates the situation and controls the aphides. The natural result is a food shortage, tlva ladybirds diminish, the aphides multiply. So fully has the value of the ladybird been recognised in America, thsit in parts where these beetles migrate to the mountains for the winter they are collected in the spring and sold by the pound to the - gardeners, whose valley farms would otherwise be attacked by green fly before* they would have moved valleywards under the influence of the warm weather. Ladybird and green fly afford but one example of the fashion in which Nature provides the antidote and sets it by the side of the poison. Nowadays we are beginning to win glimpses of the knowledge that may enable us to help ourselves in time of need. Every man or woman who has worked in ;, garden or possessed as much as a single rose knows what green fly may do to spoil the promise of the healthiest tree, but how many have looked on the underpart of the leaves or on the bark for the little yellow eggs that tell of deliverers at hand, or have watched the dark, flat, six-legged larva new from the egg moving destructive) as a flame among the unsuspecting flies? There are many other insects thai help us to grow fruit and vegetables ami flowers, but the m*st conspicuous and easily-recognised of all its the ladybird. *