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. 2 



1 See Bulletins 55, 82, and 87, Illinois Agricultural Experiment Station. 



2 See Massachusetts 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. In the 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 by Ben Leath, of 

 Kensington, Georgia, 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. 



