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. Seatter it broadeast through the 
field. Another and an effective material is poison bran mash. 
Fie. 138.— Adult of 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 species of grasshoppers develop the habit of migrating 
when excessively 2bundant. In such eases direct remedial measures 
are practically impossible. 
