GENERAL FUNCTIONS OF FORESTS. 299 
portion of them build their nests in trees, and find in their 
foliage and branches a secure retreat from the inclemencies of 
the seasons and the pursuit of the reptiles and quadrupeds 
which prey upon them. The borders of the forests are vocal 
with song; and when the gray and dewy morning calls the 
creeping things of the earth out of their night-cells, it summons 
from the neighboring wood legions of their winged enemies, 
which swoop down upon the fields to save man’s harvests by 
devouring the destroying worm, and surprising the lagging 
beetle in his tardy retreat to the dark cover where he lurks 
through the hours of daylight. 
The insects most injurious to the rural industry of the garden 
and the ploughland do not multiply in or near the woods. The 
locust, which ravages the East with its voracious armies, is bred 
in vast open plains which admit the full heat of the sun to 
hasten the hatching of the eggs, gather no moisture to destroy 
them, and harbor no bird to feed upon the larve.* It is only 
since the felling of the forests of Asia Minor and Cyrene that 
the locust has become so fearfully destructive in those coun- 
tries; and the grasshopper, which now threatens to be almost 
as great a pest to the agriculture of some North American soils, 
breeds in seriously injurious numbers only where a wide extent 
of surface is bare of woods. 
General Functions of Forests. 
In the preceding pages we have seen that the electrical and 
chemical action of the forest, though obscure, exercises proba- 
bly a beneficial, certainly not an injurious, influence on the 
composition and condition of the atmosphere ; that it serves as 
* Smela, in the government of Kiew, has, for some years, not suifered at 
all from the locusts, which formerly came every year in vast swarms, and the 
curculio, so injurious to the turnip crops, is less destructive there than in 
other parts of the province. This improvement is owing partly to the more 
thorough cultivation of the soil, partly to the groves which are interspersed 
among the ploughlands. . . . When inthe midst of the plains woods 
shall be planted and filled with insectivorous birds, the locusts will cease to be 
a plague and a terror to the farmer.—RENTzscH, Der Wald, pp. 40, 46. 
