LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 



Bureau of Plant Industry, 



Office of the Chief, 



Washington, B.C., August 16, 1910. 



Sir: I have the honor to transmit herewith and to recommend for 

 publication as Bulletin No. 196 of the series of this Bureau the accom- 

 panying manuscript entitled " Breeding Drought-Resistant Forage 

 Plants for the Great Plains Area," by Mr. Arthur C. Dillman, Assistant 

 Physiologist in Alkali and Drought Resistant Plant-Breeding Inves- 

 tigations, Bureau of Plant Industry. 



In the Great Plains area, where the rainfall is limited in quantity 

 and is of uncertain distribution, drought-resistant varieties of crop 

 plants are indispensable if farming is to be made a reasonably safe 

 enterprise. Forage plants which can be successfully grown with a 

 limited moisture supply are especially needed in order to build up a 

 well-balanced type of dry-land agriculture. The Department of 

 Agriculture has introduced from foreign countries many varieties 

 that are more, drought resistant than those ordinarily grown in the 

 United States, but even these can be further improved and adapted 

 by the use of plant-breeding methods. 



The present paper describes the preliminary results of work along 

 this line which was begun by the Bureau of Plant Industry in cooper- 

 ation with the South Dakota Agricultural Experiment Station in 

 1906, and is now being carried on by the Bureau on the experiment 

 farms at Bellefourche, S. Dak., and Akron, Colo. The progress that 

 has been made in breeding drought-resistant and otherwise improved 

 strains of alfalfa, amber sorgo, millets, Bromus inermis, and other for- 

 age plants especially adapted to the area is here reported. In several 

 of these crops new and promising strains have been developed. As 

 soon as a satisfactory test of their comparative drought resistance 

 can be had, the seed of those strains which stand the test most suc- 

 cessfully will be increased and distributed. It is believed that this 

 bulletin will be useful, not only because it points out the scope of the 

 work conducted by the Bureau of Plant Industry in this field, but 

 because it describes simple breeding methods which can be applied 

 by the farmers of the area for the improvement of their crop varieties 

 in respect to drought resistance and other qualities. 

 Respectfully, 



G. H. Powell, 

 Acting Chief of Bureau. 



Hon. James Wilson, 



Secretary of Agriculture. 



