BIRDS AND FORESTS 



BIRDS AND FORESTS 



The forest trees have many enemies. The insect is 

 by far the most formidable. Remove Nature's checks 

 on the multiplication and spread of insect life for a 

 few years, and the forests would be swept out of 

 existence. 



Like a human army the insect host is divided up 

 into regiments and battalions, and their methods of 

 attack differ one from an- 

 other. Each has its special 

 allotted task to perform. 

 Some of them attack and 

 devour the seeds and nuts ; 

 others eat up the roots of 

 seedlings. Another kind 



j . • The Cuckoo and the Oriole are 



deposits eggS in a Crevice in fond of hairy caterpillars. 



the bark of a tree. These 



hatch into grubs, which bore their way into the trunk 

 or branch and feed upon its substance. The holes let 

 in moisture and destructive fungi which gradually 

 bring about the death of the tree by slowly but surely 

 sapping its life, like a cancer in the human body. The 

 rotting eventually becomes so extreme that the tree 

 dies, slain indirectly by the grub of a beetle. 



Other kinds of grubs attack and feed on the soft 

 inner bark and sap. Caterpillars swarm over the 

 entire tree and denude it of leaves. The leaves are 

 the breathing organs of trees ; they are its lungs by 

 means of which the tree inhales carbonic acid gas and 



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