10 MASSACHUSETTS AGRICULTURE. 



one plant contains twenty or more. There they are completely 

 screened from view and all harm, while they eat out the life and 

 substance of one onion, and then pass on to the next. This is 

 their usual habit ; sometimes they eat directly through the side 

 of the plant, though not often. They pass through two or three 

 generations during the summer, but the last in the fall, instead 

 of turning to flies, remain in the pupa state during the winter, 

 and all affected onions containing them should be destroyed. 



Having learned so much concerning their habits, the question 

 arises, how can our crops be protected ? Gas lime and other 

 offensive-smelling substances have been tried in vain, for the 

 mother fly seems to delight in them. For many years my at- 

 tention has been directed to this subject, and I believe I have 

 discovered a remedy. It is the common practice to cover onion 

 seed one inch deep, and they will germinate better at that depth 

 than any other ; nearly all will germinate at two inches, while 

 none will grow if covered three inches deep. I have found that 

 by sowing the seed an inch and a half or two inches deep, the 

 young maggots fail to reach the bottom of the onion, where they 

 expect to make an entrance ; and so few attempt it at the side 

 of the plant, that the crop is but little affected. I have tried this 

 method for several years with success ; it is important, also, to 

 sow early, and to have the surface of the land highly manured, 

 to give the crop an early and rapid growth in order that the 

 plants may the sooner be too large to be affected by the few 

 maggots that do succeed in making an entrance at the side. 



The onion blight and smut, also the potato rot, are at times 

 very destructive to those crops, turning the most promising fields, 

 within a few days, to scenes of desolation. All, in my opinion, 

 are caused by parasitic plants of different varieties, growing 

 upon and consuming the vitality of the onion and potato plants, 

 and in the latter so poisoning the plant as to cause the tuber 

 rapidly to decay. The onion smut, which has more of the char- 

 acter of a fungus plant, so impregnates the land with its spore, 

 as to render it unsafe to plant onions for several years on land 

 thus affected. The parasite that produces the onion white blight 

 does not reproduce itself by seeding the land, but comes upon 

 the crop at the period of its most vigorous growth, in a dry time, 

 showing its effects perhaps in a small spot at first, but in case the 

 dry atmosphere continues, rapidly spreading over the whole field. 



