the land easier to work, and it is also more easily penetrated by the
roots of plants. The influence on aeration is also marked. The air can
more readily penetrate through the interstices in the soil, and, in
consequence, chemical changes in the soil favorable to plant growth are
facilitated.

The roots of clovers are usually so numerous that they literally fill
the soil with vegetable matter. This matter, in process of decay,
greatly increases the power of the soil to hold moisture, whether it
falls from the clouds or ascends from the subsoil through capillary
attraction. The moisture thus held is greatly beneficial to the plants
that immediately follow, especially in a dry season and in open soils,
and the influence thus exerted frequently goes on, though with
decreasing potency, for two, three or four seasons.

Reference has already been made to the tap root which clover sends down
into the soil and subsoil. In the strong varieties this tap root goes
down deeply. When the crop is plowed up, the roots decay, and when they
do, for a time at least, they furnish channels down which the surface
water percolates, if present in excess. Thus it is that clover aids in
draining lands under the conditions named. The channels thus opened do
not close immediately with the decay of the clover roots, hence the
downward movement of water in the soil is facilitated for some time
subsequently.

It has been stated that clovers have more power than some other plants
to gather plant food in the soil. In some instances they literally fill
the soil with their roots. When other plants are sown after the clover
has been broken up they feed richly on the decaying roots of the clover.
Thus it is that clover gathers food for other plants which they would
not be so well able to gather for themselves, and puts it in a form in
which it can be easily appropriated by these. The nitrogen in clover is
yielded up more gradually and continuously as nitrates than it could be
obtained from any form of top dressings that can be given to the land.
In this fact is found one important reason why cereal grains thrive so
well after clover.

Since the roots of clovers act so beneficently on soils, it is highly
important that they be increased to the greatest extent practicable.
Owing to the relation between the growth of the roots of plants and the
parts produced above ground, development in root growth is promoted much
more when the clover is cut for hay