38 INJURIOUS AND BENEFICIAL INSECTS OP CALIFORNIA. 



northern part, especially in the Sacramento Valley and the San Fran- 

 eisco Bay region. 



Food Plants. — The feeding habits of these peculiar insects are not 

 well known. Some are carnivorous, while others are believed to feed 

 upon decaying vegetable or animal matter. However, we do know that 

 they are often responsible for considerable damage to potatoes before 

 they are dug. The tubers are gnawed so as to be unfit for keeping or 

 selling. Occasionally a large proportion of the crop may thus be in- 

 jured, but this is more likely to occur only in small newly-cleared areas. 



Control.— The most injury is done in fields placed under cultiva- 

 tion for the first time or lands left for some time to sod or pasture. Well 

 cultivated fields seldom, if ever, suffer from the attacks of this pest. 

 Clean cultivation around the fences, so as to break up the breeding 

 places, will practically eliminate all possibilities of injury, but even this 

 is hardly to be recommended as a practical method of control. 



ACRIDIID^E (Family) 



SHORT-HORNED GRASSHOPPERS OR TRUE LOCUSTS 



The insects of this family include the most destructive members 

 of the entire order and are common practically everywhere. They 

 are separated from the other families by their short antennae, which 

 are seldom if ever as long as the body; by the three-jointed tarsi; and 

 by the short four-valved ovipositor. The hind legs are large and 

 strong to enable them to travel rapidly by jumping. With the excep- 

 tion of a comparatively few species all have well-developed wings 

 and some of them are able to make long and continuous migratory 

 flights. 



They are rather prolific and may increase in such numbers as to 

 cause great ruin to vegetation. Certain species habitually migrate 

 long distances, leaving a trail of devastation in their wake. The 

 eggs are usually laid at the bottom of a hole drilled into the soil by 

 the tip of the abdomen of the female. As the winter of most species 

 is passed in this stage, the eggs are thoroughly protected from 

 cold and moisture by a frothy cement secreted by the female for 

 this purpose. In the spring the young grasshoppers emerge from 

 the holes and begin to feed upon the first green vegetation and to 

 develop very rapidly. In the early fall they begin to mate, the 

 females depositing their eggs before winter. 



Control. — The control of grasshoppers is often a perplexing prob- 

 lem, due to their great numbers and migratory habits. Their appear- 

 ance is often so sudden as to take the farmer wholly unawares and 

 the damage is done before he can defend his crops. Extensive 

 experiments on control work have been conducted by trained men 

 all over the world, the results of which have made the grasshopper 

 invasions less dreaded. The reclamation of arid lands and the exten- 

 sion of agriculture to the foothills and deserts have eliminated many 

 of the old and favorite breeding places, and greatly reduced the 



