15 



CULTURAL METHODS. 



Cultural methods give greatest promise as remedies. Clean garden- 

 ing or farming with fall plowing should alwaj^s be followed, as these 

 form a most valuable measure of prevention of injury b}^ this and 

 other insects that are present in the fields. As soon as the crop is off 

 the remnants should be gathered and burned. All weeds in the vicinity 

 should be kept down thruout the year, including late fall and early 

 spring, since, as has already been shown, the common weeds of the 

 field and garden are available as alternate 

 food plants and serve as the hibernating 

 quarters of the aphides, which feed more or 

 less thruout the warmer periods of winter. 



On weeds the insects can be found feeding, III ^^^^^ '«-. 



in a climate like that of the District of 

 Columbia, untilJanuar}^, ''even after heavy 

 frosts or snow," and again in March. 



CONTROL OF THE MELON APHIS BY NATURAL 

 ENEMIES. 



The possible control of this pest with 

 the assistance of its natural enemies, aided 

 by a trap crop, 

 is proposed by 

 Mr. Sanborn, who 

 has placed at the 

 writer's disposal 

 advance sheets of 

 his publication in 

 which this method 

 is described. 



Rape, which is of 

 value for hog and 

 sheep pasture, is 

 the crop advised. 

 Kale or mustard" 

 should serve the 

 same purpose. This method begins in the fall when the trap crop is 

 planted. 



The cabbage aphis {Aphis brassicse L.) is closely related to, but 

 quite distinct from, the melon aphis. It winters over on the trap 



^'For several years the writer has observed that these two crops serve as a trap 

 for the cabbage aphis, by luring them from cabbage and more valuable crops; also, 

 that they are here largely destroyed and practically held in check by their principal 

 insect enemies — which have been illustrated in figure 3; and the idea of employing 

 this means of attracting the natural enemies was suggested to the writer in 1900. 



Fig. 6.— Knapsack sprayer in operation, showing method of applying 

 nnderspray. 



