a school, post office, and store (Little Crooked) on the 

 south-central edge of the study area and a post office 

 (Wilder) in the north-central portion. It is notable perhaps, 

 that the influx of humans and early agricultural efforts 

 coincided with the longest continuous period of above-normal 

 moisture (1907-1918) in the area since about 1850 (Fig. 3.11). 

 Years of low and high moisture were interspersed during 1919- 

 1929, resulting in abandonment of the most marginal homestead 

 sites. Extreme drought during 1930-1940 and other factors led 

 to abandonment of most remaining homesteads and general 

 depopulation of the area. By 1960, there were only 3 

 headquarter ranches and 2 seasonal (haying and winter 

 livestock feeding) operations located on the study area; there 

 were none by the 1970s. The only current inhabitants are 

 employees of the Charles M. Russell National Wildlife Refuge 

 (CMRNWR), Sand Creek Field Station, developed along Highway 

 191 in the northwest corner of the area during the early 

 1980s. 



2.8 1 



Homestead Era 

 (1905-1920) 



Study Period 



1850 1870 



1890 1910 1930 



Year 



1950 1970 



1990 



Figure 3.11 



Relative moisture index for the study area 

 during years 1850 through 1986 calculated 

 from Douglas fir growth ring data. 

 Estimates for 1981-1986 based on our 

 regressions. See Fig. 3.8 for source 

 acknowledgement . 



Abandonment of homesteads resulted in reversion of nearly 

 all formerly cultivated tracts to grassland and other native 

 vegetation along with seeding of some fields to introduced 

 crested wheatgrass (Agropyron desertorum) . Alfalfa (Medicago 



74 



