216 INSECTS AFFECTING VEGETATION 



ture at "Washington, D. C., recommends the following poison 

 mixture : 



1 pound pans green. 



2 pounds common salt. 



60 pounds fresh horse dung. 



Mix carefully and thoroughly. The paris green should be 

 mixed with water to form a paste and then stirred into the manure. 

 This mixture can best be made on a small scale in a tub or halfbarrel 

 and distributed with a trowel in the places where young hoppers are 

 thickest. It should be scattered early in the morning while the soil 

 is still wet from the first irrigation. This will help to keep it from 

 drying. 



The hopper-dozer is simply a long, shallow pan of stove-pipe 

 iron or galvanized iron mounted on runners and backed by a light 

 frame covered with cloth. The pan is about four inches deep, from 

 eighteen inches to two feet wide, and from ten to sixteen feet long. 

 It is partly filled with water and a little kerosene. A horse drags 

 the machine across the field over the stubble of the first crop and 

 the half-grown hoppers jump into the pan where the oil coats them 

 over and kills every one that it touches. The hopper-dozer works 

 best on level land. On sloping ground the oil and water run to 

 one end and slop over. To prevent this the pan is usually divided 

 into sections by a number of partitions. The runners should stick 

 out in front of the pan about a foot and one-half, and an old piece 

 of chain or heavy rope should be stretched loosely between them 

 to drag ahead of the machine and make the hoppers jump. 



In our large fields one such machine is not of much use. Sev- 

 eral of them abreast must be driven across the field, for the grass- 

 hoppers dodge around the ends of one machine and escape. They 

 cannot dodge three machines abreast so easily. On level fields there 

 are no great practical difficulties in the use of hopper-dozers. Care- 

 less driving may spill oil on some alfalfa and kill it. If these ma- 

 chines are to be really effective they must be used before the grass- 

 hoppers get their wings. The first crop should be cut as early as 

 possible and the hopper-dozers should follow the rakes as closely as 

 may be. On the whole, they should be used only w r here plowing 

 and harrowing have not been done or have failed to keep the grass- 

 hoppers in check. 



The Western Cricket. The large, black Western Cricket has 

 been very common and destructive in Nevada for several years. It 

 is not a true cricket but a wingless grasshopper. This fact, how- 

 ever, does not affect the purpose of this article for in it we aim 

 merely to discuss means of holding this pest in check. In eastern 

 Nevada, at about the time when the first crop of hay was being cut, 

 the crickets came swarming down from the hills upon the ranches 

 and did a large amount of damage to garden vegetables and to hay 

 and grain. Black and shining, clumsy and repulsive, they come sud- 

 denly, without warning, out of the sagebrush and swarm over field 

 and garden, even invading the houses. 



