SUMMARY. 33 



SUMMARY. 



The chief limiting factor in the production of crops in the Great 

 Plains area is lack of sufficient moisture. Two ways -of increasing 

 crop production in that region are: First, the use of tillage methods 

 which will conserve the moisture in the soil as far as possible for the 

 use of crops; and second, growing drought-resistant varieties. 



The object of the plant-breeding work described in this bulletin 

 is to develop strains of some of the common forage crops that are 

 more drought resistant and productive than strains now grown in the 

 region. 



Drought-resistant forage-breeding work is now carried on at two 

 farms conducted by the Department of Agriculture in the Great 

 Plains area, at Belief ourche, S. Dak., and at Akron, Colo. These 

 farms are fairly representative of a large part of the northern and 

 central Great Plains. 



In breeding alfalfa for this region, while drought resistance is the 

 principal object in view, such characters as resistance to winter- 

 killing, superior forage yield, and good seed production can not be 

 neglected. 



The results of the breeding work with alfalfa indicate that superior 

 forage production and superior seed production are not antagonistic, 

 but may be combined in one plant or strain. 



Maximum seed production in alfalfa can be obtained by growing 

 plants in hills, allowing thorough cultivation of the soil. This 

 method can be recommended only where seed is the chief object of 

 the crop. 



Breeding sorgo at Bellefourche has been undertaken for the pur- 

 pose of developing a drought-resistant and early-maturing strain of 

 good forage quality. The existence of such a strain would extend 

 the use of the crop considerably north of its present area. 



Most millet varieties now on the market are mixtures of more or 

 less distinct types. In the breeding work conducted by this office, 

 several promising types have been segregated and have shown a 

 high degree of uniformity. They will be tested further for drought 

 resistance, early maturity, and forage yield. 



Numerous species of grasses have been tested for drought resistance 

 in the course of the breeding work at Highmore, and by the Office 

 of Forage-Crop Investigations at Bellefourche and other stations in 

 the Great Plains area. Breeding work is in progress with species 

 that have proved drought resistant and otherwise valuable, includ- 

 ing smooth brome-grass, western wheat-grass, and slender wheat- 

 grass. 



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