﻿OF THE STATE ENTOMOLOGIST. 109 



■newly hatched younp-, but is most advantageously employed when they are most slug- 

 gish and inclined to huddle together, as during the first eight or ten days after hatch- 

 ing, and in the mornings and evenings subsequently. They then drive almost as 

 readily as sheep, and maybe burned in large quantities by being driven into windrows 

 or piles of burning hay or straw. Thej'^ may also be killed with l^erosene, and by 

 means of H:ittened beating implements; wooden shovels being extensively used for 

 this purpose in Eur(»pe. 



But to protect the crops and do battle to these young locust armies, especially 

 where, as was the case in much of the ravaged country in 1875, there is little or no hay 

 ■or straw to burn, the best method is ditching. A ditch two feet wide and two feet 

 deep, with perpendicular sides, offers an efltectual barrier to the young insects. They 

 tumble into it and accumulate, and die at the bottom in large quantities. In a few days 

 the stench becomes great, and necessitates the covering up of the mass. In order to 

 keep the main ditch open, therefore, it is best to dig pits or deeper side ditches at short 

 intervals, into which the 'hoppers will accuuiulate and may be buried. Made around a 

 field about hatching time, few 'hoppers will get into that field till they acquire wings, 

 and by that time the principal danger is over, and the insects are fast disappearing. If 

 any should hatch within the enclosure, they are easily driven into the ditches dug in 

 different parts of the field. The direction of the apprehended approach of the insects 

 being known from their hatching locality, ditching one or two sides next to such local- 

 ^tJ^ is generally sufficient, and where farmers joint hey can construct a long ditch, 

 whicli will protect many farms. 



With proper and systematic ditching early in the season, when the insects first 

 hatch, everything can be saved. When water can be let into the ditches so as to cover 

 the bottom they may be made shallower, and still be effective. 



A ditch three feet wide, unless correspondingly deep, will be more apt to permit 

 the escape of the insects, when once in, than a narrower one. In hopping, the more 

 perpendicular the direction the insects must take, the shorter will be the distance 

 reached. Of course the wider the ditch, if it be correspondingly deep, the more effec- 

 tual will it prove. In exceptional cases, when the locusts are nearly full grown and the 

 wind is high so as to assist them, even the two-foot ditch loses much of its value. 



.Next to ditching the use of nets or seines, or converging strips of calico or any 

 other material, made after the plan of a quail net, has proved most satisfactory. By 

 digging a pit, or boring a post auger hole, three or four feet deep, and then staking 

 the two wings so that they converge toward it, large numbers of the locusts may be 

 driven into the pit after the dew is off the ground. By changing the position of this 

 trap, much good can be done when the insects are yet small and huddled in schools ; 

 but all modes of bagging, netting, crushing with the spade or other flat implements 

 and burning, which can be employed to good advantage when the insects first begin to 

 hatch, become comparatively useless when they begin to travel in concert over wide 

 stretches of land. The same may be said of all the mechanical contrivances to facili- 

 tate the destruction of the insects ; they are useful if used in concert in a given 

 neighborhood soon after the young hatch, but subsequently do not compare to 

 ditching. 



When the insects are famishing, it is useless to try and protect plants by any 

 application whatever, though spraying them with a mixture of kerosene and warm 

 water is the best protection yet known, and will measurably answer vvheu the insects 

 are not too numerous or ravenous. 



The best means of protecting fruit and shade trees deserves separate consideration. 

 Where the trunk is smooth and perpendicular, they may be protected by whitewashing. 



