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direction of the oiled water on account of the "homing-" instinct 

 above mentioned. Young grasshoppers will not drive more than from 

 10 to 20 feet before taking what is commonly termed by the plantation 

 managers "the sulks," when they cease bopping and show an aggra- 

 vating indifference to the brush of the switches used in driving them. 

 The necessity of early learning the location of the egg-beds and the 

 time of hatching is obvious if the ditch method be practiced. 



Upon river plantations many open ditches are indispensable, and 

 when rains are sufficient to keep them filled or partly filled with water 

 they serve a most excellent purpose in the destruction of young grass- 

 hoppers. During the grasshopper campaign of 1900 over 225 barrels 

 of coal oil were used upon Dahomy and not a little of this quantity 

 was placed upon the water of the ditches of the plantation in the form 

 of emulsions. At the height of the season as many as 50 miles of 

 ditches were oiled, and the number of young grasshoppers killed may 

 be roughly estimated when we state that the surface of the water for 

 this distance was completely covered. After the water evaporated 

 the stench from decaying grasshoppers was very perceptible, and had 

 it not been for the satisfaction of knowing that millions had been slain 

 the stench, no doubt, would have been objectionable. 



Mr. Robert Glenk, a member of the experiment station staff of 

 Louisiana, spent two weeks in the field in charge of the grasshopper 

 work, and in his report to Mr. Harding, dated May 31, 1900, says: 



Sunday afternoon brought up a heavy rain and filled many of the ditches with 

 standing water. We had oiled the surface of the water and made a combined attack 

 upon the insects, which has resulted in their wholesale destruction. We are using 

 gangs of men and are making a systematic drive to the ditches. 



One hitch occurred in the use of the emulsion. In driving the tank 

 wagon over rough ground the emulsion became so thoroughly churned 

 that the oil separated and floated to the top. This condition, however, 

 was soon revealed by the effectiveness of the spray. The use of the 

 pump, which mechanically mixes the oil and water, should obviate this 

 difficulty. 



Tarred sheets and hopper dozers. — The operation of the ordinary 

 hopperdozer may be considered an easy matter in meadows, pastures, 

 and over crops planted upon the level, but one has to experience 

 once the trouble of working a hopperdozer in alluvial sections where 

 the high ridging of the land prevails to realize that the ordinary use 

 of the hopperdozer is impracticable. To construct one of these imple- 

 ments suitable to alluvial conditions will require further experience 

 and trial. During the efforts with the hopperdozer Mr. C. D. Patter- 

 son, general manager of Dahomy, improvised a tarred sheet similar to 



4670— No. 30—01 2 



