CORN CULTURE
By FREDERICK D. RICHEY, principal agronomist, Division of Cereal Crops and
Diseases, Bureau of Plant Industry
CONTENTS
Page                                  Page
Introduction-------------------   1  Planting corn--------- -------------  13
Seed corn  ---- -_---- - ------------------  2  Time of planting-----------------------  16
The soil ------------ -----------------  3  Rate of planting..----------------  18
Crop rotation -----------------------  4  Depth of planting--------------- ----  20
Green manuring ------------------------  5  Cultivation-------------------------  20
Manure --------------------       6     Importance of early cultivation----------  21
Commercial fertilizers ---.------------------  6  Later cultivations ------------------  22
Applying fertilizer - -------------------  8  Cultivating listed corn------------------  23
Preparing land for corn --------------------  9  Economy in cultivating-----------------  23
Erosion and soil blowing--------------  9  Insects injurious to corn-------------------  24
Time of plowing-------------------------  11 Diseases of corn-------- -------------  26
Depth of plowing------------------------  12
Final preparation-----------------------  12
INTRODUCTION1
CORN PROBABLY ORIGINATED in southern Mexico, Central
America, or northern South America.         Certainly it was
unknown to the rest of the world before the discovery of America.
Now it ranks with wheat, rice, and oats in world production as one
of the four leading cereal crops. About three fourths of the immense
total world crop is grown in the United States, where corn is
by far the most important single crop, exceeding in production and
value wheat, oats, barley, rye, rice, and buckwheat combined. Corn
is grown in every State in the Union, about 100 million acres of land
being planted to this crop each year (fig. 1).
The concentration of dots in figure 1 shows the importance of the
different areas in contributing to the total acreage in corn. Only in
the Corn Belt, a somewhat indefinite area in the Central States where
the concentration of dots is greatest, does any considerable part of
the corn crop leave the counties in which it is produced. Even there
the crop is consumed largely on the farms where it is grown, furnishing
the bulk of the feed for American livestock.
The largest average acre yield of corn for the United States in
any year was 31.5 bushels in 1920. In spite of this, more than 100
bushels per acre have been produced in many parts of the United
States. Some large yields have been obtained by methods that are
unprofitable or impractical on a large scale. Others, however, have
required only such labor and expense as are entirely warranted in
practical corn production. These show clearly that materially larger
acre yields of corn can be had.
The distribution of the dots in figure 1 indicates also the widely
diverse conditions under which corn is grown. The length of the
1 The photograph reproduced on the title page is used by courtesy of the U.S. Army
Air Service.

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