ROOTS AND TUBERS FOR FORAGE 307 



beets rank first, as they have about 20 per cent of dry matter, three-quarters 

 of which is sugar. Mangels, rutabagas and turnips frequently have no 

 more than 10 to 12 per cent of dry matter, not more than one-half of which 

 is sugar. 



Some of the flat-topped turnips that grow principally on the surface 

 of the ground may be grown for pasturage and are readily eaten by sheep. 



The dry matter in roots is slightly lower in feeding value, pound for 

 pound, than that in cereals. It is about equal in digestibility to the dry mat- 

 ter in cereals. 



The yield of some of the more important root crops, as grown at a 

 number of experiment stations, is as follows: mangels, average yield in 

 tons per acre during five years in five localities, 31; rutabagas, same locali- 

 ties and same number of years, 26.5 tons per acre; carrots, same localities 

 and same number of years, 23. G tons per acre; sugar beets, same localities, 

 average five years in two of them and three years in other three, 20.6 

 tons per acre; turnips, three localities average of five years, 21.3 tons 

 per acre. 



The cultural methods of most of the crops, brief description of which 

 will follow, are given in the chapter on "Vegetables and Their Require- 

 ments." 



Sugar-Beets. — While sugar-beets have a high feeding value they are 

 not extensively grown as forage because the yield is generally much less 

 than can be secured from mangels and rutabagas. The by-products of the 

 sugar factories in the form of beet pulp is quite extensively used as roughage 

 for livestock. For cultural methods of beets see not only the chapter above 

 referred to, but also the chapter on " Sugar Crops." 



Mangels. — Mangels differ quite materially from sugar-beets in form, 

 color and size. Sugar-beets grow mostly in the ground, are tapering in 

 form, and both the skin and flesh are white. Mangels average four times as 

 large, are more cylindrical in form, and a considerable portion of the root 

 grows above ground. The flesh of the mangel is usually reddish or yellow, 

 while the skin may be white, red, golden, purplish or even black. Mangels 

 are planted in rows twenty-eight to thirty-six inches apart. The rate of 

 seeding ranges from six to eight pounds of seed per acre. The seed should 

 be covered about one inch deep and as soon as the plants are well established 

 they should be thinned by use of a hoe to little groups of plants at intervals 

 of twelve inches. These should be thinned later by hand to one plant to 

 each place. They should be cultivated to destroy weeds and maintain a 

 good soil mulch. They are generally harvested by plowing a furrow on one 

 side of the row, and are pulled by hand. On account of their large size they 

 require much cutting before being fed. They may be stored in root cellars 

 or in pits, and call for a low, uniform temperature and fair ventilation during 

 the storage period. 



Turnips and Rutabagas. — There are a great variety of turnips. Ruta- 

 bagas or Swedes are but a few of the large growing varieties that are espe- 



