38 HINTS ON SOILS AND FERTILIZERS 
NATURAL METHODS OF ENRICHING THE 
SOIL 
There are two important and practical ways 
by which the soil may be enriched, naturally. 
These methods are the addition of green 
manure and barnyard manure. We will con¬ 
sider the green manure proposition first. A 
green manure crop is a crop that is raised for 
the express purpose of plowing it under when at 
a certain stage of growth. There are many such 
crops raised by the farmers of this country an¬ 
nually, for the purpose of improving the tex¬ 
ture of their farm land. Crops such as rye, or 
clover, make excellent green manure crops. 
They should be turned under, or plowed under, 
when still green, but not when they have grown 
too rank. If turned under when they are tall 
and coarse, this serves as a check for the rise 
of the capillary moisture, and the following 
crop is liable to dry out, due to the interception 
of the capillary moisture from below. 
Leguminous crops, or crops that manufacture 
nitrogen in small nodules on their roots, by 
means of bacteria, are the best green manure 
crops to raise, because they not only improve 
the texture of the soil by their decaying 
vegetative matter, but also add considerable 
nitrogen to the soil as well, because of the 
activities of the bacteria present in the roots of 
such plants. As nitrogen is an important 
eleme*t in the soil, this factor is being con¬ 
sidered seriously by many farmers to-day, in 
their efforts to increase the nitrogen supply of 
their soils. 
