632 MISCELLANEOUS FARM SUBJECTS 



total yield of crop, just as the breeders of sugar beets must increase 

 the yield of beet sugar per acre rather than the tonnage of the roots, 

 and the breeders of dairy cows increase the yield of butter rather 

 than the yield of milk. Thus we should add to the protein content 

 of our cereal and forage crops. In case of corn fodder there is a 

 special reason for increasing the content of protein. The varieties 

 of corn used for dry fodder or for silage already yield so well that 

 a super-abundance of roughage can easily be produced. But to 

 make it valuable as a balanced ration we must add to it expensive 

 concentrated foods, such as bran, oil cake, or other grain products. 

 By increasing the percentage of protein in the fodder or silage 

 a less amount of the expensive grain foods will be required, and, 

 the ration being cheaper, will leave a larger margin of profit. But 

 of even greater importance is the breeding up of the nitrogen con- 

 tent in clover, cowpeas, alfalfa, and other plants which gather nitro- 

 gen from the air. These crops should not only have their nitrogen 

 content increased, but they should also be so bred as to succeed far 

 better than now and under far wider ranges of conditions. Red 

 clover, for instance, has been improved comparatively little since 

 it was brought from Europe. It thrives well under some conditions, 

 yet it does not meet all the difficulties and is not profitable in some 

 localities where it should be made very useful. If it could be grown 

 under conditions where it is not now hardy, its use as a fertilizing 

 agent would be greatly extended, and if it were bred to extract still 

 larger amounts of nitrogen from the air, it would be more valuable 

 as a fertilizer and also as a food for domestic animals. Mr. W. T. 

 Swingle proposes that the nitrogen-gathering bacteria associated 

 with the nodules on the clover roots could also be bred so as to be 

 more actively useful; and since brewers have successfully bred 

 special varieties of brewing yeast for making beers of different quali- 

 ties, the breeding of these bacteria would seem also to be a practical 

 undertaking. The field pea, likewise, is a crop worthy of most 

 serious effort, both that varieties may be secured which will produce 

 profitable crops in localities where it is not now successfully grown, 

 and that the contents of its seeds and its vines and leaves may have 

 a larger percentage of this most valuable element, protein. Alfalfa, 

 cowpeas, and soy beans, for like reasons, should be improved. 

 These are the five principal nitrogen-producing plants of this coun- 

 try, each with its special very large field of usefulness. To change 

 each plant so that its range of successful production would be en- 

 larged 10 per cent, its protein content increased 10 per cent, and ita 

 yield increased 10 per cent where now grown, would cost only a 

 very small fraction of the resulting increase in value. Increasing 

 the protein content in this manner would in the aggregate be a very- 

 large increase of the nitrogen annually gathered from the air into 

 the soil of the country. Since the sugar content in sugar beets has 

 been so greatly increased, an increase of the protein of clover from 

 15 per cent of the dry matter to 16.5 per cent or even to 20 per cent 

 should not be impracticable. But, important as may be the increase 

 in nitrogen, breeding so as to adapt these crops to conditions where 



