50 



BULLETIN 823, U. S. DEPARTMENT OF AGRICULTURE. 



At the Akron substation, in northeastern Colorado, there is little 

 choice between the early and midseason varieties. At the Cheyenne 

 Field Station, at an altitude of 6,000 feet, in southeastern Wyoming, 

 the midseason varieties of oats have yielded better than the early 

 ones. 



RESULTS IN THE SOUTHERN GREAT PLAINS AREA. 



The southern Great Plains include the western or semiarid por- 

 tions of Texas, Oklahoma, and Kansas, southeastern Colorado, and 

 eastern New Mexico. 



The oat crop is not grown extensively in this area. The early 

 red varieties, Red Rustproof and Burt, and the early yellow varieties, 

 Kherson and Sixty-Day, are the most popular. 



Varietal experiments with the Kherson, the Sixty-Day, and other 

 oat varieties have been conducted under dry-land conditions at only 

 two experiment stations in this section. The Kherson and the 

 Sixty-Day varieties have been under test at the Amarillo Cereal 

 Field Station, Amarillo, Tex., since 1906. Comparable data are 

 available from the Hays Branch Experiment Station, Hays, Kans., 

 only since 1913. 



The climate of this section, like that of the northern Great Plains 

 area, is generally classed as semiarid. As crop production is largely 

 governed by climatic conditions, the altitude, the quantity and 

 distribution of the annual precipitation, the normal annual and 

 seasonal precipitation, and the mean temperatures for June, July, 

 and August at Hays, Kans., and Amarillo, Tex., are shown in Table 

 XXXVIII. The general soil type at each station also is shown. 



Table XXXVIII. — Altitude, averaje annual and seasonal precipitation, mean seasonal 

 temperatures, and general soil types at the Hays (Kans.) Branch Experiment Station and 

 the Amarillo (Tex.) Cereal Field Station 





Alti- 

 tude. 



Climatological data. 





station. 



Length 

 record. 



Average pre- 

 cipitation. 



Normal temperature 

 (°F). 



General soil type. 





Annual, 



Sea- 

 sonal.i 



June. 



July. 



August. 





Hays, Kans 



Amarillo, Tex 



Ft. 



2,000 

 3,676 



Yrs. 

 48 

 26 



Ins. 



23.16 



20.89 



Ins. 



17.67 

 15.67 



2 71.6 



3 72.0 



2 76.8 



3 73.3 



2 76.9 



3 75.3 



Silty clay loam. 

 Chocolate clay loam. 



April to September, inclusive. 



2 Twelve-year average. 



3 Eighteen-year average. 



Table XXXVIII shows that the greater portion of the precipita- 

 tion occurs during the growing season, when the need for it is greatest. 

 The high mean temperatures and high wind movement cause rapid 

 loss of water by evaporation. As oats require more water than any 

 other small-grain crop, the conditions just mentioned are not favor- 

 able to their best development. 



