GRASSHOPPERS 



143 



When the insects have been abundant, all suitable breeding places 

 should be deeply plowed in the fall. Alfalfa may be disked. In 

 gardens or similar locations poison bran mash may be used, if poultry 

 can be kept out. 



In field crops two methods of direct control are in general use. 

 The insects may be poisoned, or they may be caught in so-called 

 " hopper-dozers." For wholesale poisoning a fairly satisfactory sub- 

 stance is the home-made material known as the Criddle mixture. 

 Take five pails of horse manure, dissolve two pounds of salt in a 

 pail of water and stir in one pound of Pairs green or London purple, 

 and moisten the manure with this. Scatter it broadcast through the 

 field. Another and an effective material is poison bran mash. 



Fig. 138. — \du\t oi Camnula pellucida. Original. 



The hopper-dozer consists of a long, shallow, sheet-iron pan, the 

 bottom covered with wet carpet or burlap and liberally dosed with 

 kerosene. Along the back of the pan is fixed a shield of canvas about 

 three feet high, and this also is wet with kerosene. The pan is drawn 

 sidewise over the ground by a man at each end, or by horses. The 

 grasshoppers jump as the pan reaches them, come in contact with the 

 kerosene in the pan or on the shield, and are killed by it. The scheme 

 is satisfactory only if put into use while the insects are still in their 

 wingless stages. 



Certain specie^: of grasshoppers develop the habit of migrating 

 when excessivel.v ?bundant. In such cases direct remedial measures 

 are practically impossible. 



