THE DIFFERENTIAL LOCUST. 



21 



Attention was first called to the 190-i outbreak b}' Mr. W. H. 

 Brown, of Navasota, whose plantation l3'ing along the Brazos River 

 was visited by the writer April 1. At this time the 3'oung hoppers 

 had been at work for about ten days, and were still hatching. The}^ 

 occurred in countless numbers around the edges of cultivated fields 

 and on uncultivated ground among the weeds, from which they were 

 migrating to the 3^oung crops as the food supply became scarce. In 



Fig. 10.— Melanoplus differentialis: young nymph— enlarged (author's illustration). 



such situations old logs were so covered with the young as to be com- 

 pletely blackened by them. The "stand"' of young corn and cotton 

 had airead}" been destroyed over several acres. In one field, where 

 they first appeared, Mr. Brown had used dry Paris green and had 

 largely checked the injury. It was found that by plowing fields where 

 the stand had been badly injured or was poor, large numbers of the 

 young hoppers were destroyed by burying, and the remainder migrated 

 4o the weeds at the edges of the fields. While still 3"oung the}^ can not 

 be readily driven as is possible when the)" are half or more nearly 

 grown. All of the vegetation around the edges of the fields was 

 therefore poisoned with Paris green or green arsenoid. In some csi^e ; 

 the poison was mixed with fiour, which 

 made it more adhesive. Over the fields. 

 ))oth those which had been plowed and 

 those wherein the hoppers were feeding, 

 poisoned bran mash was distributed, 1 

 pound of Paris green being mixed with 25 

 pounds of bran. This treatment proved 

 exceedingly etfective. Five days later, when again visited, the great 

 majority of the hoppers were found dead among the weeds which 

 had been thoroughly poisoned. The effect of bran mash is not so 

 apparent, as the hoppers after eating it crawl })eneath small clods of 

 earth and there die, but by examining the ground around a small pile 

 of the mash from 12 to 20 dead hoppei's were found, and many more 

 had doubtless died farther awav. To moisten the mash, water is found 

 as effective as molasses. Around the edges of the fields, and in patches 

 of weeds on uncultivated land, a spray of pure kerosene or of strong 



Fig . n . — Egg- m a "s of Meln » oplus difier- 

 riit/(d/.'<—(;i\hiriiv(\ (author's illus- 

 tration). 



