INJURIOUS INSECTS OF 1903. 9 



carried by the wind or actually flown from the neighboring 

 farm, even though a third of a mile away, or they may have 

 possibly come from flax seeds on volunteer stuff overlooked 

 on the edges of the field. It is more than probable that the 

 first explanation is correct, illustrating very forcibly the need 

 of co-operation. 



The life history of this pest has been thoroughly discussed 

 in previous reports from this office, notably that of last year, 

 and need not be repeated here. The same might be said of rem- 

 edies and methods of prevention, but in order that this informa- 

 tion may be as widespread as possible among our farmers, the 

 latter are repeated here. To these I will add a suggestion, that 

 varieties of wheat which produce a stiff' straw be planted as far 

 as possible, or that the land be so handled that, it will grow 

 strong straw, capable of standing up in spite of the ravages of 

 the fly. The Fifes may fill these requirements, supposing the 

 soil is in proper condition. One must clearly distinguish be- 

 tween the two terms "strong straw" and rank growth," the 

 latter being undesirable, since it results in weak straw. Con- 

 ditions of the soil which produce a "rank growth" of straw, 

 therefore, are to be avoided. 



REMEDIES AND MEANS OF PREVENTION. 



1. Bvu'n the stubble when, from any reason, shallow plowing 

 is unavoidable, or when plowing is to be delayed in the spring 

 until after emergence of flies. If the stubble is left long it will 

 bvirn easier. Some farmers are willing to go to the trouble of 

 spreading straw from threshing over the stubble, thus insuring 

 the burning and at the same time getting rid of some "flax seeds" 

 which may have lodged on the surface of the straw pile at the 

 time of threshing. It is well, however, to remember that re- 

 peated burnings, from the standpoint of* our chemists, are not 

 good for the soil. 



2. Fall plowing of the stubble in such a way that the straw 

 is completely turned imder. In this connection we should not 

 overlook the fact, made evident from the findings of 1903, that 

 volunteer wheat, wherever found in the fall, may contain flax 

 seeds. 



