212 RESOURCES OF CALIFORNIA. 
California, and I fear that we have not yet seen the worst of 
them, though several times during the last fifteen years they 
have eaten every green thing within large districts. They 
come in millions upon millions, and darken the air, moving for- 
ward at the rate of a mile or two a day, and leaving no grass 
or leaf behind them. Grains, grass, weeds, kitchen vegetables, 
and fruit-trees, are alike eaten bare of every green particle. 
Grasshoppers are abundant in countries where the summers are 
dry, the winters warm, and the vegetation vigorous; and if a 
large extent of land be uncultivated, they will occasionally be 
SO numerous as to destroy every green thing. They are bred 
in the hills of California, and after dry winters descend into 
the valleys, usually content to eat the wild grasses, but some- 
times attack the cultivated fields. There is no known method 
of killing them after they have entered a field, or of driving 
them away from it; but they may be kept out by digging a 
trench, putting straw in it, with some moist straw on top, and 
then setting fire to it. The grasshoppers do not like the fire 
and smoke, and will try to avoid them. 
Under the head of the grape and the orange, I have spoken 
of the bugs which infest them. The army-worm has been seen 
in California, but has done little damage as yet. The curculio 
and weevil are not known in the state. The Canada thistle, 
the mullen, and the dock, have been introduced, but have not 
yet given much trouble. 
§ 156. Neat Cattle—California has 1,100,000 neat cattle, 
900,000 sheep, and 150,000 horses, nearly all bred in the open 
air and open plains, and fed only on wild grasses, The system 
of breeding live-stock differs much in California from that 
which prevails in the Atlantic states, where cattle are kept in 
fields and stables all the time, and fed with cultivated food.* 
Here domestic animals grow more rapidly, and reach their full 
development earlier, than east of the Sierra Nevada. 
§ 157. Spanish Cattle—Most of our neat cattle are of the 
old Californian breed, brought hither by the Spanish mission- 
aries from Mexico, about 1770. At what time their stock 
