22 THE CEREALS IN AMERICA 



reproduction and the inheritance of variations in these parts is 

 recognized as possible. 



Only useful characters should be selected, because two char- 

 acters are more difficult to develop than one ; three more diffi- 

 cult than two, and so on. Some characters are mutually 

 antagonistic, as extreme earliness and either great size or pro- 

 ductiveness. To select wisely requires deep study and good 

 judgment. Varieties frequently deteriorate on account of 

 unwise selection. This is especially true of maize, although it 

 IS the field crop which it is the easiest to select. 



44. C. Testing Power of Specific Forms to Reproduce Them- 

 selves. — Having selected a desired form, it is next necessary to 

 test its ability to transmit its characters. Even though the sire 

 (plant furnishing the pollen) may be known, there is no cer- 

 tainty that the plant will transmit the characters which it pos- 

 sesses. Different grains from the same head of wheat are 

 known to yield unequally. Some variations are easily fixed : 

 others require generations of selection before the characters can 

 be depended upon. Under ordinary farm conditions the ability 

 of individuals to reproduce themselves is not tested, and fur- 

 nishes a very important reason why little progress has been made 

 in the improvement of field crops. Take timothy, for example. 

 A casual inspection of a field of timothy will show that there is 

 a great variation in the length of head, the length of stem, the 

 amount of leaves and number of stalks per stool. Under the 

 usual method no selection is exercised, and no test of the power 

 of the transmission of characters is possible. A few experi- 

 menters have selected plants (stools) having different character- 

 istics and by planting 100 seeds from each plant in rows, one 

 seed at a place, have obtained remarkable results. After the 

 ability of the plant to transmit its characters has been demon- 

 strated, the seed can be rapidly multiplied for field purposes. 



It is well understood by livestock breeders that the best 

 individual does not always produce the best progeny. It is a 



