FIBER CROPS 187 



Boll rots are caused by various fungi and bacteria that cause 

 the bolls to rot, especially when there is abundant rainfall. 

 Injury to the surface of the bolls by insects permits entrance 

 by these organisms, though some of them are not dependent 

 on a broken surface for their entrance. Where these troubles 

 are serious, one should try to secure seed from noninfected 

 cotton and use varieties that do not produce excessive foliage. 

 Early-maturing varieties and dwarf stalks are less damaged by 

 these diseases than the later-maturing varieties of rank growth. 



II. FLAX 



237. Production and treatment. Although flax is one of the 

 important fiber crops of the world and is grown somewhat ex- 

 tensively in the United States, it is grown here almost wholly 

 for the production of seed. Linseed oil, used principally in the 

 manufacture of paints, is extracted from the seed ; and the 

 linseed cake, the product that is left after the oil has been 

 extracted from the seed, is a valuable food for stock. The area 

 devoted to flax in the United States is approximately two and 

 three-fourths million acres, yielding about twenty million bushels 

 of grain. The straw, aggregating several million tons, is usually 

 wasted or burned. No attempt is made to recover from the 

 straw the fiber it contains, although competent authorities 1 

 assure us it is quite the equal of the average straw from which 

 the Russian peasants obtain the fiber for the principal linen 

 fabrics of the world. The reason for this failure of the Ameri- 

 can farmer to utilize the fiber is, in large measure, the high 

 cost of labor. 



The fineness and quality of the fiber depend upon the thick- 

 ness of the stand and the uniformity of the growth. When the 

 flax is sown for the production of seed, only about one fourth 

 as much seed is used as when it is sown for the production of 

 fiber. Whenever the growth is checked by drought or other un- 

 favorable conditions the quality of the fiber is injured. Flax 



1 Farmers' Bulletin 274, United States Department of Agriculture. 



