558 Bulletin 78. 



This spring we potted out a thrifty cabbage plant, and May 25, 100 small 

 maggots were introduced around the base of the plant. The next day when 

 the maggots had become established on the root, 4 oz. of a solution of salt (i 

 pound to one gallon of water) was poured in an excavation around the base 

 of the plant. This treatment resulted in the death of most of the maggota 

 and the plant also ; it was thus more eflfectual than the kainit of the same 

 strength. Thus all the evidence is against the use of salt to destroy the 

 maggots, unless it is desirable to destroy the plants at the same time. 



Dry Lime or Lime Water. 



Lime in a dry condition has been extensively used as a preventive against 

 the maggots, but the literature contains only a few references of its use as a 

 killing agent. In her report for i88r. Miss Ormerod says caustic, lime was 

 not very eflfective as it could not easily reaeh the roots. In 1888, the "Rural 

 New Yorker" reported that plants treated with air-slaked lime to kill the 

 maggots suflfered more than those untreated. Last year Butz and Baldwin in 

 Pennsylvania, and Washburn in Oregon used the dry lime with partial suc- 

 cess. It is thus very doubtful if the lime used dry will destroy any of the 

 maggots. 



Lime Water. — The source of nearly all the recommendations for the use 

 of lime water to destroy the maggots is a report by Miss Ormerod in 1881 

 from one of her correspondents who soaked the lime 48 hours and then appli- 

 ed it with apparent good results. We doubt if lime in any form will either 

 prevent or kill the maggots. 



(<:) By the use of Insedicidal Substances. 



London Purple or Paris Green. 



London Purple. — Prof. Cook experimented with this in 1887. Several 

 applications were made about the roots of early cabbage, beginning soon after 

 the plants were set and continuing until after the flies had stopped egg- 

 laying. "At this time an examination of the plants showed them to be 

 nearly as badly infested with maggots as were the untreated rows." 



Paris Green. — In 1886, Prof. Cook reported that Paris Green was used at a 

 strength of i pound to 40 gallons of water for the maggots. "It neither in- 

 jured the plants nor the insects." In 1890, Mr. Fletcher treated a dozen 

 plants with it (i lb. to 100 gals.); its application noticeably checked the 

 growth of the cabbage, and it failed to kill the maggots. 



Pyre thrum. 



In 18S6 and 1887 Prof, Cook tested this substance thoroughly, both as a 

 powder and as a decoction in water, but without any effect whatever. 



Tobacco Water. 



In the "Country Gentleman" for 1859, p. 27, we find the first recommend- 

 ation of this tobacco decoction to kill the maggots ; it had been tried as a 

 preventive several years before. The first experiment we find recorded is by 

 Prof. Cook in 1887. He faithfully used a strong decoction "about radish 



