9 



few will fly from other quarters for the continuation of the species. 

 Thus injury may be greatly curtailed if not absolutely prevented for 

 an entire season. The large size and bright colors of the insect render 

 it easy of detection and its sluggish nature assists in its easy capture. 

 Mr. H. Walter McWilliams, Griffin, Ga., reports that by offering 

 a bounty to school children for the destruction of this pest he suc- 

 ceeded, in March and April, 1902, in destroying the first generation in 

 that vicinity, and estimated that this experiment saved him $100 on 

 his cabbage crop alone, not counting the benqfit to the children. 



As instance of the ease with which this insect may be hand-picked, 

 a grower at Denton, Tex., gathered, in February of one year, 47,000 

 bugs. In case hand-picking has not been thoroughly done and some 

 bugs have escaped this process and succeeded in depositing their eggs, 

 the masses, wdiich may be easily recognized by comparison with fig- ' 

 nre 1, 5, should be carefully gathered and crushed. 



Kerosene emulsion^ according to the testimony of many who have 

 experimented with it, is not elfective against the adults and only par- 

 tially effective when sprayed on the younger nymphs. Quite recently 

 Prof. A. F. Conradi " has found that a 10-per-cent kerosene emulsion 

 is effective in killing the nymphs, as is also whale-oil soap, at the rate 

 of 2 pounds to 4 gallons of Avater. If the insects are sprayed just 

 after they have molted these insecticides almost invariably kill them. 

 It is obvious that further experimentation is desirable along this lino. 

 ' Other remedies. — A. few words should be said of other remedies and 

 may be prefaced with the. remark that since the harlequin cabbage 

 bug feeds exclusively by suction and does not chew its food, the ar- 

 senicals, hellebore, and such remedies as are useful against cabbage 

 worms are absolutely valueless against the present species. Pyre- 

 thrum is not effective and is, moreover, too costly. Hot water applied 

 at a temperature of about 130° F. to the infested cabbage plants should 

 be tested. It is not applicable, how^ever, to large fields on account of 

 the difficulty of maintaining the temperature at a given point, but 

 may be found useful in kitchen gardens. 



The value of hand torches for insecticidal purposes is extremely 

 limited. The plumbers' torch is used considerably in Texas as a 

 means of killing this insect, but growlers are apt to expect too much 

 of this method, and to apply it to too many kinds of insects, to the 

 ultimate detriment of their crops. 



It is possible that some of the natural enemies of this species, 

 especially southern egg parasites, might be utilized in its control; i. e., 

 by shipping parasitized eggs from localities where they are abundant 

 to northern regions in which they do not occur. 



« Bill, so, Texas A sir. Exp. Sta.. pf). 9-11, 1007. 

 [Cir. 103] 



