292 THE FORAGE AND FIBER CROPS IN AMERICA 



with the sugar beets. They generally require, especially common 

 turnips, rather sandier soils than beets. Stiff clays are objec- 

 tionable on account of the difficulty of producing a fine seed-bed, 

 while light sandy and gravelly soils are undesirable because of 

 the lack of surface moisture. 



368. Cultural Methods. The preparation of the soil and the 

 cultivation, harvesting, and storing of the crops are similar to 

 mangel- wurzels. If anything, a finer seed-bed is required, but 

 the more rapid growth and the single seed make cultivation and 

 thinning easier. These crops should never be grown continu- 

 ously upon the same ground and should never succeed one 

 another. The famous Norfolk four-course rotation which helped 

 to revolutionize the agriculture of England in the seventeenth 

 century consisted of turnips; grain, usually barley; "seeds," a 

 mixture of clover and grasses; grain, usually wheat, each one 

 year. In the United States, rutabagas may occupy the same 

 place in the rotation as suggested for mangel-wurzels. 



369. Seeding. Common turnip seed may vary from 200,- 

 ooo to 260,000; rutabagas from 160,000 to 190,000; kohlrabi 

 from 115,000 to 130,000; and cabbage from 80,000 to 140,000 

 seeds per pound. The germinating power should not be less 

 than 90 per cent., although it frequently is in commercial seed. 



The number of plants per acre should be for cabbage 7,000 to 

 10,000; for rutabagas and kohlrabi 20,000 to 30,000; for common 

 turnips somewhat more. Four pounds of rutabaga and hybrid 

 turnip seed and three pounds of common turnip seed are usually 

 sown when in rows 27 to 36 inches apart. Seeds should be sown 

 at a depth of one-half to three-fourths inch. Small hand garden 

 drills are available for this purpose. Turnips, kohlrabi, and ruta- 

 bagas must be thinned as directed for beets. 



Cabbage may first be planted in flats in the greenhouse or 

 cold-frame and transplanted to the field by hand or by means 

 of the cabbage planter; or a few seeds may be dropped in the 

 field every 18 to 24 inches apart in the rows and the plants 



