DISEASES OF CULTIVATED PLANTS 607 



dead, are easily pulled up, the roots breaking off easily at about the 

 level of the furrow slice. 



Upon examination, most of the smaller branch roots are found 

 to be dead, as well as the tap root below the point at which it breaks 

 off. These dead roots and the parts of the tap root already diseased 

 have a very characteristic ashen gray color. Many nearly mature 

 plants which are attacked late in life show this dead gray aown one 

 side of the tap root only. The leaves, side branches, and a strip 

 of the main stem above this portion are dead, giving a peculiar one 

 sided blighting, similar to the appearance of a tree struck by 

 lightning. 



If the disease is sowed with the seed upon breaking, but a few 

 plants are attacked the first year; and, at flowering time, dead plants 

 will be seen to be quite evenly distributed in the drills. If weather 

 conditions are quite favorable, each new infection increases suffi- 

 ciently in area to reach over and attack plants in two or three adja- 

 cent drills. These infection areas are nearly always circular in 

 outline, and become much enlarged if flax is seeded there the fol- 

 lowing year. The first year these spots may reach a diameter of one 

 to three or four feet. The second year these same areas are usually 

 much more than doubled, so that it takes but three to five flax crops 

 upon such lands to make the infection general. 



Because of the peculiar and characteristic manner in which 

 all young plants and the soft parts of more mature ones droop and 

 wilt when attacked, as if through drought or intense heat, it is 

 thought best to call the disease flax wilt. Though the trouble may 

 be properly referred to as flax sick soil, the term flax wilt will prove 

 distinctive. (N. Dak. E. S. B. 50.) 



How to Treat Flax Seed. There are some difficulties connected 

 with treating flax which are not encountered in handling other 

 grains. When I first recommended the formaldehyde treatment for 

 wheat and oats, a number of farmers complained that it injured 

 their seed. In so far as I have been able to investigate any of those 

 cases, the trouble has been due to some defect in the manner in 

 which they carried out the work. I hope that no farmer will under- 

 take to treat his flax seed until he has read the directions here given 

 very carefully. While the amount of seed to be handled over is 

 much less than in the case of oats and barley, one must do the work 

 very much more carefully. I have only to call attention to the 

 fact that the mere wetting of flax seed, unless it is quickly dried, 

 is injurious to its germinating qualities. One ought, therefore, in 

 treating flax, to be very careful not to use a bit more of the solution 

 than is necessary to dampen the grain. If by accident you should 

 chance to supply more moisture to a batch of seed than you ought 

 to do, throw in some more dry seed at once and stir it over rapidly. 

 The dry seeds will withdraw the excessive moisture from those which 

 are too wet, and thus prevent injury to the latter. 



I would not recommend that any one should undertake to treat 

 all his seed flax this year. Try a sufficient amount to sow an area 

 large enough from which to harvest the seed for next year's crop. 



