418 Agricultural Gazette of N.SJF. [Jf«y 2, 1908. 



tlie h()[)pei's, wliicli ina\' tlicu he (!• stroycd liy "il .•mil sodp spiiijs, l)iiiiiiii<^ 

 over, or drajryinf:; a \oy^ tlii'ouyh the trenches. Spraying a 10-foot strip of 

 the edge of the erop \\ itli an arsenic spray (say 1 Hi. arsenate of lead to 

 25 gallons of water) destroys a large percentage before tliey have done nmeh 

 damage. Similarly poisoTied baits (bran 10 lb., arsenic I lb., with I lb. 

 treacle, mixeil ^\\'y, and made into a mash with water) can be used wilh good 

 effect by scattering pellets along the edge of a <-ro)>. Corn-stalks, or grass, 

 I'l'c., cut and soakeil in a strong arseinc solution also form efJ'ective baits. 

 Care must be taken in the case of liaits and arsenic spi'ayingto prevent stock 

 gaining access. 



The foliage ( f larksjmr (Del phiniinn) is fuhnd to poison locusts tliat feed on 

 it., as also does the foliage of the castor-oil plant (Ricinus communis). 



Strips of fire, and even grass fires where able to be controlled, have been 

 used over small ai-eas as a last resource to desti'oy dense swarms. 



The " hop)perdozer " is used about the breeding-grounds, in orchai'(k and 

 young crops, etc. These can be nuide any size on the principle figured in 

 Fig. G, and drawn by one or two horses. It consists in having a shallow iron 



Fig. 6. " Hopperdozer." 



tray a')out 3 inches clt^ep, anything from (i up to K! feet wide, and '2 or .'5 feet 

 from front to ba^k. At thf^ back a light framework bearing a cloth or light 

 iron sci'een, as tigured, is needed. Blue oil or kerosene is poured into the 

 tray, and the hopperdozer drawn to and fro through the swarm. Great 

 numbers ai'e destroyed by hopping into the tray, or against tlie screen, from 

 whence the}' fall into the oil. The dead ones soon accumulate, and the trav 

 needs to be occasionally cleam^d out and fresh oil added. Nunibei's may hop 

 out again, but, once wetted by the oil, eventually die. The bottom of the 

 hopperdozer should be mounted on several wooden I'uimers, and a light pole 

 fastened in fi' ait to trail about a foot in fi-ont of the pan ami cause the 

 hoppers to rise. 



Winged swarms are difficult to cope with. Snnidging —that is, lighting a 

 line of smoke tires to the windward of a crop or orchard — frequently deteis 

 a flying swarm from settling. 



Control Over Large Areas. 



The sjjread of some fungus disease, such as Mucor racemosus E mpusa 

 (jrylli, by iiKjculating swarms, suggests itscdf as a cheap, inexpensive, and easy 



