8 BULLETIN 995, U. S. DEPARTMEXT OF AGRICULTURE. 
Worn soil. — In those sections where sugar beets have been grown 
for a number of years without proper attention to the maintenance 
of soil fertility and an adequate supply of humus, the yield has been 
reduced. There are few sugar-beet areas in which the soil fertility 
has been maintained or improved to the limit of possibilities. It is 
apparent, therefore, that by proper attention to soil conditions from 
the standpoint of fertility the average yield of beets per acre may 
be greatly increased. The worn condition of the soil is not peculiar 
to the growing of sugar beets, but occurs in the growing of other farm 
crops, when attention is not given to increasing the supply of avail- 
able plant food in the soil or to maintaining its humus content. 
Quality of the soil. — Soils vary widely in their original qualities, 
both physical and chemical. All agricultural soils are supplied in 
varying proportions with the necessary plant foods for crop produc- 
tion. Soils that have plant food present in great abundance may 
be said to be rich. They are not fertile, however, unless these plant 
foods are in soluble form or unless the} 7 are rendered soluble as 
rapidly as the various materials are required by the plant in the 
process of growth. The quality of the soil from the standpoint of 
fertility may be greatly improved by proper cultivation, crop rota- 
tion, and the addition of humus, as well as by the application of lime 
or other material that will improve its physical condition. At times 
special treatments, such as subsoiling and drainage, are needed to 
make the soil highly productive. 
SUBSOIL. 
In the growing of sugar beets the subsoil is often of equal im- 
portance with the surface soil. 
Hardjxm.— Frequently the surface soil is underlain by a hardpan 
which it is impossible for the beet roots to penetrate. The hardpan 
may be of natural formation or it may be induced by improper till- 
age. If it is close to the surface and of such material that it can not 
be broken up successfully, the profitable growing of sugar beets is 
impossible. Beets produced under such conditions will be short, with 
a resulting low tonnage, or they will be pushed out of the ground 
and consequently will be low in sugar and purity. The nature of 
the hardpan is of considerable importance in this connection. If it 
is of rock and near the surface, little can be done to improve its 
condition for sugar-beet culture, but if it is simply a close and com- 
pact form of soil it may be broken up with a subsoil plow. Some- 
times local areas of extremely hard subsoil are found in the sugar- 
beet sections, and this condition constitutes a limiting factor in the 
production of this crop in those areas as a whole or on certain farms 
or fields, depending upon the location and distribution of the hard- 
