486 FIELD GROP8 



remainder of the plant are quite similar to those described 

 for the production of flax fiber (Sec. 306). The principal 

 enemy of hemp is broom rape, a parasitic plant, which is 

 best combated by rotation of crops. 



The best quality of fiber is produced when hemp is retted 

 under water, as is the custom in some of the European 

 countries. Dew-retted hemp is dark in color and the fiber 

 produced from it is rather coarse. Most of the hemp grown 

 in the United States is used for the manufacture of ropes and 

 of warp for carpets. 



SUPPLEMENTARY READING 



Farmers' Bulletins: 



217. Essential Steps in Securing an Early Crop of Cotton. 



285. The Advantages of Planting Heavy Cotton Seed. 



286. Comparative Value of Whole Cotton Seed and Cotton- 

 Seed Meal as Fertilizers for Cotton. 



290. The Cotton Boll worm. 



302. Sea Island Cotton. 



314. A Method of Breeding Early Cotton to Escape Boll 

 Weevil Damage. 



326. Building Up a Run-Down Cotton Plantation. 



333. Cotton Wilt. 



344. The Boll Weevil Problem. 



364. A Profitable Cotton Farm. 

 Cyclopedia of American Agriculture, Vol. II. 

 Burkett and -Foe's Cotton. 

 Burkett's Farm Crops. 

 Lamborn's Cotton Seed Products. 



Thompson's From the Cotton Field to the Cotton Mill. 

 Wilcox and Smith's Farmers' Cyclopedia of Agriculture. 

 Boyce's Hemp. 

 Bureau of Plant Industry Circular 57, The Cultivation of Hemp 



in the United States. 



