FRIENDS AND ENEMIES OF PLANTS 187 



obtained from the State Superintendent of Public. Instruction and 

 from the National Audubon Society. 



Common Animals. As in the case of insects we find that some 

 of our common animals are harmful, some are beneficial, while 

 others are harmful or beneficial according to circumstances. All 

 animals that live on a vegetable diet may be regarded to a certain 

 extent as enemies of plants. In the whole list there is no greater 

 enemy of plant life than man himself. Millions of trees are cut 

 down every year to supply his demands for lumber and for the 

 wood pulp needed in the manufacture of paper. Hodge in his 

 book on Nature Study says: " It has been estimated that we have 

 five hundred million acres in growing forests, and that thirty-five 

 cubic feet of wood are annually produced per acre. Annual con- 

 sumption of wood, according to Professor Farrow, is probably 

 double the amount produced. Inferences from these facts are 

 obvious." Unless this waste is checked, it will be only a short 

 time until there will be practically no forests of any note in this 

 country. 



But while in this particular instance man seems to be an enemy 

 of plant life, it is also equally true that in many other instances 

 certain plants would not be able to live and thrive except for the 

 protecting influence of man. Many trees, shrubs, and garden 

 plants could hardly exist without the constant attention and care 

 of man. 



Harmful Animals. In the list of harmful animals we may class 

 in a general way, rabbits, rats, mice, gophers, goats, etc. 



Rabbits. Our common rabbits are very widely distributed 

 and are often very destructive on account of their vegetarian diet. 

 The cottontails, or small species of rabbits, do a great deal of dam- 

 age by gnawing the bark of fruit trees and devouring the young 

 plants in our gardens and truck patches. West of the Mississippi 

 there is a larger species, known as the jack rabbit, which is quite 

 famous on account of its remarkable speed. It is also quite 

 destructive, and is one of the worst pests known on the farm. 

 Fruit trees may be protected to some extent against rabbits by 

 placing common screen wire or gauze around the trunks of the 

 trees at the bottom. Whitewashes containing tar, carbolic acid, 

 and poison have also been recommended, but are regarded by many 



