554 Bulletin 78. 



maggots. Many later writers have included this method among their rem- 

 edies for the pest. Of course, there can be no question of its effectiveness in 

 checking the insect, but every plant thus destroyed represents considerable 

 labor to the gardener, besides the reduction it makes in the profits when the 

 crop matures. We believe there is no occasion for the practice of the method. 

 The maggots may be killed in several ways, as has been shown, without 

 injury to the plant. 



{b) By Ihe Application of Direct or Indirect Fertilizers. 



Ammonial Liquor. 



This refuse liquor from gas works was used by one of Miss Ormerod's cor- 

 respondents in England in i88r. It was diluted with about twice the quantity 

 of water, and one pint of the dilution was applied around the stems of each 

 plant. Three or four such doses saved only the plants that were not too far 

 gone when the treatment was first applied. We doubt if the liquor would 

 kill the maggots ; it would probably simply encourage or stimulate the plants 

 to send out enough roots to support itself and the maggots also. 



Soot. 



Last year, at the Pennsylvania Experiment Station, soot was sprinkled 



about some cabbages which were found infected by the maggots. It seemed 



to save a few plants. No definite opinion can be formed from this single 



experiment. Wherever soot is plentiful, its destructive powers should be 



further tested. 



Ashes. 



In i86r, Mr. Gregory advised that ashes be used around the plants to 

 destroy the maggots. Mr. G. H. Howard, in 1888, said that a small handful 

 of wood ashes put down around each stem is a sure remedy if applied in 

 time, that is, before the maggots have destroyed the bark and roots of the 

 plants. However, Prof. Cook, in 1886, used unleached ashes against the 

 maggots with no success. When sprinkled on the foliage the plants were 

 seriously injured. Last year, Washburn in Oregon, had fairly good results, 

 but the ashes had to be applied frequently. Possibly enough ashes could be 

 applied to the maggots to kill them, but the amount that could be safely 

 applied to the plants doubtless acts simply as a fertilizer thus enabling the 

 plant to make roots enough for itself and the maggots. Mr. Howard evi- 

 dently implied this when he stipulates that the bark and roots must be intact 

 or the ashes are not eflFective. Thus, we do not believe ashes can be relied 

 upon to destroy the maggots. 



Nitrate of Soda. 



In 1 88 1, a correspondent reported to Miss Ormerod that an application of 

 a solution of this substance 'saved only a few plants. Mr. Fletcher reported 

 in 1887 an experiment by one of his correspondents which indicated that the 

 substance might act remedially. In 1891, Prof. J. B. Smith recorded his 



