CLASSIFICATION OF CORN 47 



account of tlie manner of pollination and because manj^ corn 

 plants are usually grown together, crossing very generally 

 results; that is, pollen from one plant fertiUzes the ovaries 

 of other plants, so that corn is usually cross-pollinated. 

 In fact, this habit is so general that a stalk growing by itself 

 seldom, if ever, produces a good ear, because of imperfect fer- 

 tilization of the flowers. 



50. Mixing of Varieties. The flowering habits of corn 

 make it extremely difficult to maintain pure varieties, as 

 they will mix at considerable distances. For this reason 

 it is highly desirable for a community to grow but one 

 variety. If adjoining farms produce different varieties, 

 each is very likely to be mixed with the other. In favorable 

 weather, the pollen grains may be carried by the wind at 

 least 200 rods, if there is no obstruction in the way. The 

 fact that the prevailing winds in the corn belt are from the 

 southwest during the season of the year when corn is blos- 

 soming is made use of to some extent by locating the seed 

 plat from which seed for the next year's crop is to be selected, 

 where the wind blows from it to the other corn fields, rather 

 than from the other corn fields to it. 



CLASSIFICATION 



51. Variation. All the varieties now so common in every 

 section of the country are the result of selection and breed- 

 ing from the original Indian types, which were very inferior 

 to those grown at the present time. Very little was done to 

 improve corn until the middle of the nineteenth century, but 

 during the past seventy years improvement has been very 

 rapid till at present there are hundreds of named varieties. 

 Some of these varieties mature in 90 to 100 days and produce 

 small ears with shallow kernels, while others require 140 or 

 more days to mature and produce large, deep-kerneled ears. 

 In color, corn kernels may be yellow, white, red, black, blue, 

 or a mixture of some of these colors and shades. The cobs 



