2 BULLETIN 291, U. S. DEPARTMENT OF AGRICULTURE. 



lished settlers in this region are those who have depended on live 

 stock as their main source of income. In favorable seasons grain 

 crops are profitable, but the profit from growing them can doubtless be 

 increased if a portion of the grain is consumed on the farm as feed for 

 animals. In the driest seasons, however, when small grains are likely 

 to be a total failure, forage crops sufficient to carry animals through 

 the winter can nearly always be depended on. This is because the 

 most drought-resistant forage crops can be raised on a much smaller 

 supply of moisture than the grain crops.' 



The native range is used to a large extent for summer pasturage, 

 but it is necessary to produce under cultivation most of the forage for 

 winter feeding, and it is often necessary to supplement the summer 

 pasturage with cultivated crops. It is evident, therefore, that forage 

 crops should occupy a very important place in the agriculture of the 

 Great Plains. 



In some sections of the northern Great Plains alfalfa, brome-grass, 

 and other perennial crops give excellent results, but certain annual 

 forage crops appear to be much more dependable in the central 

 Plains. Two of the most suitable crops for this region are the millets 

 and sorghums. IMillets grow and mature in a comparatively short 

 season and are often able to escape drought when other crops are 

 overtaken. Sorghums endure drought well, standing a long period 

 of drought and yet renewing growth upon the return of favorable 

 conditions. Both crops have a very low water requirement. 



ADAPTATIONS TO DROUGHT IN MILLET AND SORGO. 



ROOT DEVELOPMENT. 



Millet has a comparatively shallow root system with a great devel- 

 opment of fine fibrous roots. It is therefore well adapted to make 

 the best use of light rains which wet the soil to a depth of only a few 

 inches. The early root growth is somewhat slow, so that the young 

 plants are sometimes injured by high winds before the roots are well 

 enough established to hold the plants firmly. Sorgo has a much 

 deeper root system than millet and can apparently make use of mois- 

 ture which is stored 3 or 4 feet deep in the soil. Both crops draw 

 heavily upon the supply of soil moisture and are likely to use for 

 their growth all of the water that is available in the area penetrated 

 by their roots. 



EARLY MATURITY. 



The period of growth of the crop is of great importance under dry- 

 land conditions. The ideal crop is one that will mature in a short 

 season and therefore lessen the risk of being overtaken by drought. 

 The short-season crop has the further advantage of allowing the soil to 

 lie fallow for a considerable period of the year when moisture conserva- 



