FARMERS' BULLETIN 1714

frost-free period, soil type, quantity and distribution of rainfall,
temperature, diseases, and the insect pests differ from locality to
locality. It is impossible to give detailed instructions for growing
a corn crop successfully under conditions that differ so widely, not
only from place to place but from day to day. Certain general
principles can be laid down, however, which will assist the individual
grower to follow methods suited to the immediate local conditions.
The State agricultural experiment stations can make many specific
recommendations as to corn-growing practices shown by careful
experiments to be successful locally. Persons interested in growing
corn should by all means write to the experiment station in the State
Each dot represents
FIGU\ 1.--Map showing000 acre s
FIGURE 1.-Map showing acreage in corn in the United States, 1929. (Prepared by the
Bureau of Agricultural Economics from census figures.)
in which they expect to grow the crop for its recommendations as to
varieties, rotations, fertilizers, and the better local cultural practices.
SEED CORN
Even the most carefully selected varieties of corn are only hybrid
mixtures and consequently are changed rapidly by selection under
different conditions. For this reason a varietal name tells little about
the corn except in a very general way. Thus, Reid yellow dent
grown in central Iowa will require several days less to mature than
the Reid grown in central Missouri. Similarly, Reid as grown in
much of West Virginia is even more quickly maturing and has
smaller ears. Again, selection in some States toward the so-called
utility type of ear during recent years has created strains of Reid
that tend to be longer eared with fewer rows of kernels and with
shallower indentation than called for by the standard descriptions
of Reid a few years ago. All of these strains properly are called
Reid. Any two of them may differ, however, much more markedly
in growth habit and yield than Reid and Johnson County white se

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