32 BULLETIN 9C5, U. S. DEPARTMENT OF AGRICULTURE. 
to in order to control the destructive pests, but a large number of the 
sugar-beet pests, including some of the fungi and bacteria as well 
as insect pests, may be controlled by crop rotation. 
Effect of sugar beets upon other crops. — As a rule, the ell'ect of 
sugar beets upon succeeding crops is beneficial. This is especially 
true of the small grains; that is, small grains grown after sugar beets 
will almost invariably produce larger yields than when these grains 
folloAv other crops. The sugar beet does not gather nitrogen from 
the air and transform it into plant food, but, owing to its long main 
root and its uneven feeding rootlets, it gathers a considerable quan- 
tity of several soluble mineral salts and stores them in the beet crown, 
and Avhen the beet tops are fed to live stock and the manure returned 
to the soil considerable fertility is added. In addition to this im- 
proved fertility of the soil the methods of cultivation employed in 
growing and harvesting the beet crop put the soil in splendid tilth, 
thereby forming good seed and root beds for the crops that follow 
the beets. Although sugar beets are grown primarily for the cash 
value of the roots as a source of sugar, the feeds obtained from the 
beet tops, molasses, and pulp, and the increased fertility and improved 
tilth of the soil are recognized as indirect benefits to the beet growers, 
and are important factors in considering the advisability of growing- 
sugar beets. These indirect benefits due to sugar-beet growing have 
only a remote bearing upon the price paid for beets and upon the 
price of sugar. They should, however, be considered in figuring the 
profits derived from sugar-beet culture. 
COMPETING CROPS. 
Crops grown in competition with sugar beets may or may not be 
suitable for rotation with sugar beets. By competing crops is meant 
those crops grown in sugar-beet areas which appear to be more profit- 
able or more easily produced, or for some reason are so favored by 
the farmer that he may possibly prefer them to sugar beets. Some of 
the competing crops do not lend themselves readily to a rotation with 
sugar beets. In such cases the competing crops may be a limiting 
factor in sugar-beet production on an individual farm, or if the crop 
is a general one it may be a limiting factor in sugar-beet production 
in a given community. A crop may compete with sugar beets because 
of its market price, because of the small amount of labor involved in 
its production,- because of the peculiar fitness of the soil for the grow- 
ing of that crop, because of local market conditions, or because it fits 
more closely the requirements of the individual farms than any other 
crop. The competing crops in the sugar-beet sections are beans, to- 
bacco, potatoes, muskmelons, alfalfa, and grains. Other crops may 
temporarily be competing with sugar beets, and some of those men- 
tioned may for local or other reasons temporarily cease to be compet- 
