THIRD ANNUAL YEAR BOOK — PART VI. 2B5 



thirty or forty ears for the breeding plat which show the greatest num- 

 ber of desirable type characteristics. Shell off the tips and butts of these 

 ears and plant three kernels in a hill by hand, carefully covering with a 

 hoe. When the hills are three feet six inches apart each way a field 

 twenty-eight rows wide and one hundred and twenty-seven hills is an 

 exact acre. This is a field of convenient size and shape. Plant each 

 row with corn from a single ear. The corn which is left can be planted 

 around the seed plant to protect it from foreign pollen. The most difficult 

 problem is to keep the variety pure and free from all mixture. The 

 difficulty arises from the fact that pollen from other fields will drift 

 for a long distance. The breeding plat, therefore, should be in an isolated 

 spot, if possible, or surrounded for a distance of forty rods with corn 

 of the same variety. This is an important point for the reason that 

 cross fertilize with inferior and barren stalks, even of the same vari- 

 ety, is detrimental to the development of desirable variety character- 

 istics and the weeding out of unavoidable types. The best corn land 01 

 the farm should be selected for the breeding field. The preparation of 

 the seed bed shoul.l receive most careful attention and should be of such 

 a character as to insure favorable conditions for germination and plant 

 growth. The cultivation should be such as will conserve moisture and 

 remove all weeds without injury to the roots. As soon as the tassels 

 appear and the ears begin to set, it is necessary to go through the ileld 

 several times, every other day and remove all weak, inferior and barren 

 stalks and suckers. It is impossible to give too much care to this work 

 for every inferior and barren stalk produces pollen which will fertilize 

 the seed of the plat. Cross fertilization of this kind must be prevented; 

 otherwise, little progress can be made toward establishing a prepotencv 

 for the production of fruitful, vigorous stalks which develop uniform 

 ears of desirable type and quality. At the Illinois station, in five years, 

 as a result of this weeding out process, the per cent of barren stalks has 

 been reduced from 60 per cent to 12 per cent. In the fall each row 

 should be husked separately. Examine the ears from each row and select 

 for next year's breeding field from those rows producing the largest pro- 

 portion of ears true to type. The ears which have produced this large 

 proportion of desirable ears must be prepotent. It is the business of 

 the corn-breeder to improve his corn by selecting and planting these ears 

 which have inherited this prepotency. 



When this plan is pursued and the same type of ear selected year 

 after year, a marked improvement in type and quality gradually adds to 

 the value of tne variety for seed purposes. If the breeding has been for 

 the purpose of changing the composition of the kernel, the results may 

 mean much to feeders, stockmen, and glucose factories. This is true, 

 for if the per cent of protein can be increased by breeding, the corn be- 

 comes more valuable as a feed for live stock because it is more nearly 

 a balanced ration. On the other hand, an increase in the oil content is 

 of great importance to the glucose factories and by decreasing the per 

 cent content of these elements a larger per cent of starch is obtained'. 

 18 



