6 



BULLETIN" 917, U. S. DEPARTMENT OF AGRICULTURE. 



The Greeley district is close to the mountains, and the mean annual 

 temperature there is 47° F., as compared with 51° for Fort Morgan. 

 The range between extremes is wide. The nights are cool and the 

 days, as a rule, are warm. The summer temperatures of the Rocky 

 Ford district are somewhat higher than those of the Fort Morgan 

 and Greeley districts. Throughout the entire territory cloudy days 

 are the exception. 



High winds, which are a characteristic feature, usually blow with 

 great persistence in the spring, when the fields are without vegeta- 

 tion. Thus, it is a common occurrence for loose soil to be picked up 

 and carried along with each strong current of air. If one of these 

 heavy winds occurs when the plants are small and the soil is dry, 

 much damage may be done to the crop. The seed is sometimes blown 

 out or too deeply covered. Plants are left with their root systems 

 exposed or covered by deposits of dust. At other times the sand 

 carried by the wind cuts the tender plant leaves. Windstorms often 

 damage a young crop to such an extent that it is necessary to reseed 

 it. In some of the longer settled districts this difficulty has been 

 reduced by the growth of windbreaks. These heavy winds accom- 

 panied by a low atmospheric humidity often cause the formation of 

 hard crusts on the soil and produce excessive evaporation, which tends 

 to counteract all the beneficial effects of a rain. Cultivation as soon 

 as possible after rainfall is essential for the best results. 



SEASONAL DISTRIBUTION OF LABOR. 



Before a cropping system can be intelligently established on the 

 farm, it is necessary to study the distribution of labor by months 



for the various crops 

 in the proposed plan. 

 Certain crops must 

 be planted at the 

 same time, and 

 therefore the land 

 must be prepared 

 at the same time; 

 others must be cul- 

 tivated simultane- 

 ously; while others 

 must be harvested 

 during the same 

 period. In fact, every operation on two or more crops may con- 

 flict with others. It is necessary then to plant only as many acres 

 of these crops as can be handled by the available labor. 



In the diagrams presented (figs. 3 to 8), no crop has been consid- 

 ered for more than one district. Although there is a slight difference 



MAN HOURS 



MONTH 



HORSE HOURS 



8 A 







1 



4 8 







i 



JAN 

 FEB 

 MAR. 

 APR. 

 MAY 

 JUNE 

 JULY 

 AUG. 

 SEPT. 

 OCT 

 NOV 

 DEC. 



1 











853B 



















































? 



1 



Fig. 3. — Labor distribution by months in growing field beans in the 

 Greeley district of Colorado. 



