8 



The best remedy, liowever, and one that should be put into opera- 

 tion by every cabbage grower who is troubled by this pest, consists in 

 planting an early crop, which may be either mustard, rape, or kale, 

 as a lure for the first-appearing insects. Radish and turnip serve a 

 similar purpose. In the Gulf States the overwintered adults appear 

 in February and March, and in the District of Columbia and vicinity 

 in the latter jDart of April. For some reason they appear to prefer 

 the plants that have been enumerated, and wild mustard and other 

 crucifers, for the first deposition of their eggs. On these crops and 

 on weeds the insects can be killed with kerosene or by the hand torch 

 or may be collected in nets, or they may be destroyed by burning the 

 entire trap crop when this is of no s^oecial value. Numerous reports 

 have been received at the Department of Agriculture, and others have 

 been recorded, of the value of trap crops as a means of controlling 

 this pest. Some of these are worth repeating. 



The first test of the trap-crop remedy was made by Lincecum 

 (1. c.) in Texas, in 186G. Noticing that the bugs were numerous on 

 mustard and radish in April, he handpicked them and thus protected 

 his cabbage crop. The practical utility of this method, however, does 

 not appear to have been recognized until considerably later. In 

 1891, Mr. H. E. Weed, when entomologist of the Mississippi Agri- 

 cultural Experiment Station, sowed a row of mustard through the 

 center of a 1-acre field of cabbage. In April this mustard attracted 

 the bugs in large numbers and on it they w^ere killed with undiluted 

 kerosene, with the result that throughout that season the field re- 

 mained free from the pest, whereas the previous year the crop was 

 almost entirely destroyed." 



Hand methods. — If determined efforts are made to stamp out the 

 first generation fewer insects will remain to be dealt with and very 



"^A correspondent, Mr. .J. H. Hevej', Ingoiuar, M'iss., tested the trap-crop 

 remedy, and wrote that wben the bugs made their appearance on a bed of mus- 

 tard he destroyed them by " bugging," i. e., by shalcing them into pans of water 

 on which a thin film of kerosene was floating. When the mustard was removed 

 to malce room for another crop a few cabbage phints became infested, but the 

 bugs were killed as above, and finally, after the middle of July, none was left. 



One of the largest growers of cabbage in Delaware reported (Sanderson, 

 Bui. 2(J, n. s., Bur. Ent., U. S. Dept. Agric, p. 07, 1!K)0) that at one time it was 

 impossible to raise cabbage on account of this pest, but for several years he 

 had used kale as a trap crop, and as a result of this procedure and careful 

 handpicking of the few bugs that strayed to the cabbage, he had been troubled 

 very little, wliile his neighbors' cabbage had frequently been mined. 



In April of one year in Maryland half an acre of kale became freely infested 

 on one side by harlequin bugs. The insects had all congregated on this side. 

 Under the writer's direction this portion was burned, straw being used to 

 facilitate ignition. Two weeks later not a single bug could be found in a walk 

 about this patch, and the cabbage which was growing in several jtlats in the 

 vicinity was free from injury. 

 [Cir. 103] 



