68 PRINCIPLES OF FARM PRACTICE 



A Minnesota farmer would probably decide to raise flint 

 corn rather than dent corn, because the former matures more 

 quickly. But he would have to make a choice among several 

 varieties of flint corn. He might choose Smut Nose because 

 his neighbors had found that it yields well, or the Golden 

 Nugget for some other reason. 



If plants are to be produced, the seed must be capable 

 of germination. There is no way of knowing this except by 

 testing. For small seeds it is sufficient to choose one hundred 

 seeds at random and place them between two pieces of damp 

 cloth or paper, keeping them moist and warm until they have 

 had time to sprout. The number which germinates determines 

 the percentage of good seed. The rate of seeding or planting 

 may then be based upon this percentage. If the seed tests 

 fifty per cent pure, the rate of planting should be doubled. 

 A different method generally used for testing seed corn is 

 described in Chapter VIII. 



Seed should be free from dirt and weed seed; from dirt, 

 because of its effect on the rate of seeding, and from weed 

 seed, because weeds interfere with the growing crop. It is 

 not always possible to get perfectly clean seed, especially 

 among small-seeded plants, such as grasses, but every pre- 

 caution should be taken to reduce the impurities. The 

 value of farm seeds free from weeds is discussed in greater 

 detail in a chapter on weeds. 



Finally, seed should not be infected with disease-producing 

 germs. Seed will be pure in this respect if produced by 

 perfectly healthy plants. But this assurance is not always 

 possible. In cases of infection by oat smut or potato scab, 

 a special treatment of the seed will destroy the infection. 

 Details of the cause and control of plant diseases will be 

 found in Chapter XV. 



