182 INTRODUCTION TO BOTANY 
Six well-defined types of corn are recognized, but only four 
are of much economic importance. These are pop corn, with 
small kernels and with endosperm all or nearly all horn-like ; 
flint corn, with much horn-like endosperm and a grain too hard 
to be fed to most animals without being ground; dent corn, 
with the kernels indented at the outer end; and sweet corn, in 
which most of the starch of the endosperm is replaced by a 
kind of sugar. Of these four kinds dent corn is by far the most 
important, constituting the great bulk of the crop in the corn 
belt. Each of the types of corn has many varieties; of dent 
corn alone more than three hundred have been named and 
described. Most of these varieties are found to show slight 
variations, which make them more or less desirable for the 
corn grower, and his efforts must be directed mainly toward 
improving the quality of existing kinds. 
173. Qualities sought by the corn breeder.1 Of the many 
qualities that may be sought by the corn grower four of the 
most important are (1) productiveness ; (2) high percentage of 
proteins; (3) high percentage of oil; (4) low percentage of oil. 
With reference to (1) it suffices here to say that the aver- 
age yield of corn for the entire United States, according to 
statistics for 1908, was a little over 26 bushels per acre; for 
the New England States, with soil no better than the aver- 
age, and with a poorer climate, it was 40.5 bushels; and for 
some New England growers it was 100 or more bushels per 
acre. No small part of the difference between the average 26- 
bushel yield and the 100-bushel yield depends on the choice 
of seed, though cultivation and soil are also important factors.? 
1 See Bulletins 55, 82, and 87, Mlinois Agricultural Experiment Station. 
2 See Massachuselts Crop Report, May, 1910. 
Throughout the Southern states and elsewhere boys’ corn clubs are coming to 
be extensively organized. The object of these clubs is to grow more and better 
corn by choice of the best seed and by thorough cultivation. Inthe State Corn 
Club Show held at Atlanta, Georgia, in December, 1912, there were exhibits 
made by 70 boys who had each grown 100 or more bushels of corn to the acre. 
The state record for a boy’s crop (raised at a profit) is held hy Ben Leath, of 
Kensington, (:eorgia, who in 1911 grew 214 bushels and 40 pounds of corn on 
one acre, at a net profit of $182.60. See Bulletin 175, University of Georgia. 
