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Natural drainage. — Fortunately a large part of the tillable area 
now devoted to sugar-beet culture has a natural drainage. This may 
be due to one of several conditions. 
(1) The surface of the ground may be sufficiently rolling to drain 
naturally. In some instances the slope is so great that the water 
passes off too quickly, and consequently the land is unproductive 
because of excessive surface drainage. 
(2) Certain areas have a natural drainage due to a sloping sub- 
soil. As previously noted, some areas have a subsoil that is more 
or less impervious to water. If the impervious subsoil is sloping, 
the water falling upon the surface soil will pass through to the sub- 
soil and gradually disappear along the sloping subsoil. In this case 
natural drainage is satisfactory and needs no particular attention 
provided the impervious subsoil is not too near or too far from the 
surface, and provided further that there is a natural outlet, so that 
the water will not eventually back up along the slope or incline of 
the subsoil. 
(3) The natural drainage accomplished by means of a porous 
subsoil has been already noted. There are localities in which the 
subsoil is so porous that it is. almost impossible to hold sufficient 
water in the seed and root beds to produce a crop of beets. There 
are therefore localities in which the natural drainage is of such a 
nature, either through a lack of of moisture or through an excess of 
water, that natural drainage constitutes a limiting factor in sugar- 
beet production. 
On the other hand, there are areas and fields in which artificial 
drainage must be practiced in order to put the soil in condition for 
sugar-beet production. Several systems of artificial drainage are 
in general use. 
The Of en ditch. — An open ditch constitutes one of the methods by 
which this limiting factor of excessive moisture is removed. It is 
the least expensive method of providing artificial drainage, especially 
from the standpoint of labor and material involved. However, 
considerable tillable ground is lost through the construction of open 
ditches. This loss is due to the space occupied by the ditch and by 
the ditch bank. In constructing an open ditch these points should 
be kept in mind, so that the least possible loss of tillable area will 
result. The open ditch constitutes a barrier which can not readily 
be crossed in the usual farming operations. It is advisable, wherever 
practicable, to construct these ditches along the edges of the field, 
along roadsides, and in places where they will interfere least 
with the farming operations. Sometimes it is necessary to cross 
the fields with ditches in order to drain the soil properly; in such 
cases the fields and ditches should be so laid out that the ditches 
