2 BULLETIN" 242, U. S. DEPARTMENT OF AGRICULTURE. 



parison either of the crops grown here and at other stations or of 

 different methods of producing them at this station. Better yields 

 have been obtained with corn at both of these stations, but as there 

 are no results from other crops with which to compare them they are 

 not given in this publication. At Tucumcari the work has not been 

 carried on for a sufficient length of time to obtain averages or to 

 warrant the drawing of definite conclusions. It is probable, how- 

 ever, that what may be said of crops at the other three stations under 

 consideration will, in a general way, also apply to the Tucumcari 

 district. 



With this brief statement the work at these three stations will not 

 be further considered, and the study will be confined to the results 

 obtained at Garden City, Dalhart, and Amarillo. Although these 

 stations are located some distance apart, they are confronted by gen- 

 eral problems that are much the same, the local differences being in 

 their intensity rather than in their nature. In order that the char- 

 acteristics of this section may be more clearly understood, a brief ac- 

 count of the climatic and soil conditions is given here. 



CLIMATIC CONDITIONS. 



In a general way the climatic conditions at each of these three sta- 

 tions, in so far as they materially influence crop results, may be 

 briefly described as follows: A limited annual rainfall of irregular 

 distribution, a high wind velocity, a very high rate of evaporation, 

 possible hail, and in the higher altitudes violent fluctuations in tem- 

 perature. All of these factors will be discussed separately and for 

 each station under consideration. 



PRECIPITATION. 



Rainfall is the most important factor influencing crop production 

 in this section. In determining its influence, it is important that the 

 distribution be considered as well as the total quantity. In a great 

 many instances the distribution may have even greater influence than 

 the total annual precipitation in determining crop production. It 

 frequently happens in the case of torrential rainfall that a large per- 

 centage of the water will be lost by run-oft'. On the other hand, fre- 

 quent light showers may at the end of the year give a large aggre- 

 gate rainfall. These light showers wet only the surface soil, and the 

 moisture may be lost by evaporation before another shower falls. 

 Consequently, light showers may be of little value to growing crops. 

 In any study of annual precipitation records of the distribution must 

 be considered before its effects can be completely understood. To 

 afford some means of general comparisons, the annual rainfall record 

 for each of these three stations is given in Table I. 



