16 THE BOOK OF FORESTRY 
Regarding the general effects of forest, geographers 
maintain that at least twenty per cent of every country 
should be covered with forest growth, and that the 
desert conditions in Northern China and in parts of 
Southern Asia are largely due to wholesale forest de- 
struction carried on for centuries. In fact, some of 
the fertile valleys mentioned in the Bible are now dry, 
barren and desolate as a result of the reckless destruc- 
tion of forest growth. 
Forests and Game.—The effect of forest cover on the 
presence of game and birds must be taken into account. 
For a long time the campaign to protect our furred 
and feathered friends was carried on solely by nature- 
lovers, tender-hearted people who loved the birds and ani- 
mals and preferred to keep the forest populous with its 
glad-hearted inhabitants. Game conservation means more 
than a kind heart nowadays, for recent investigations 
indicate how close is the balance as maintained by 
Dame Nature. If man, in his eagerness to shoot, de- 
creases numbers of birds, insect attacks will almost 
immediately increase in severity. In fact the spread 
of the cotton boll weevil in the Southern States is ex- 
plained by some as resulting from killing off the prairie 
chicken. 
By examining the crops of the birds common to 
orchard and forest it bas been found that most of 
them are of enormous service to the farmers and fruit- 
growers by eating the scale or insects that prey upon 
the gardens and orchards. The forest and woodlot 
furnish ideal nesting and breeding-places and, as pre- 
viously explained, the presence of forests on our water- 
sheds is necessary in order to keep our trout brooks and 
fish ponds full the year round. 
Some overzealous lovers of the woods think that they 
