s of
nitrogen, of which 2 pounds are deposited in the grain itself and 1
pound in the straw or stalks.

(2) In live-stock farming one-fourth of the nitrogen in the food
consumed is retained in the animal products--meat, milk, wool, and
so on--and three-fourths may be returned to the land in the
excrements if saved without loss.

(3) When grown on soils of normal productive capacity legumes secure
about two-thirds of their total nitrogen from the air and one-third
from the soil.

(4) Clover and other biennial or perennial legumes have about
two-thirds of their total nitrogen in the tops and one-third in the
roots, while the roots of cowpeas and other annual legumes contain
only about one-tenth of their total nitrogen.

(5) Hay made from our common legumes contains about 40 pounds of
nitrogen per ton.

(6) Average farm manure contains 16 pounds of nitrogen per ton.

Question: How many tons of average farm manure must be applied to a
40-acre field in order to provide as much nitrogen as would be added
to the soil by plowing under 2-1/2 tons of clover per acre? Answer:
400 tons.

Either method will furnish about as much nitrogen as would be taken
from the soil by a 50-bushel crop of wheat, a 75-bushel crop of corn
or a 100-bushel crop of oats per acre. The decision by the
individual between live-stock farming and grain farming should be
based upon preference and profit rather than upon the erroneous
teaching that farm manure is either essential or sufficient for the
maintenance of soil fertility in this country.

Bread is the staff of life, and many must sell grain. I do not
advise all grain farmers to become live-stock farmers; but I do
advise both grain farmers and live-stock farmers to enrich their
soils by practical, profitable and permanent methods. Both classes
of farmers may secure new nitrogen--that is, they can positively
increase their nitrogen supply by sufficient use of legume crops.

How to Supply Nitrogen

The cotton-grower who sells cotton lint at 10 cents a pound and the
market gardener who sells from $100 to $300 worth of fruits and
vegetables from one acre may well make liberal use of commercial
nitrogen at 15 or 20 cents a pound; but if after deducting the cost
of harvesting, threshing, storing and marketing the average farmer
receives only 1 cent a pound for his grain and if 40 per cent of the
commercial nitrogen applied is lost by leaching, then the total crop
of grain would bring only