2 CIRCULAR 491, U. S. DEPARTMENT OF AGRICULTURE 



richest sources of information has been the exchange of observations 

 among various students of Plains agriculture whose experiences 

 extend over the last 30 years. 



The recognized dearth of factual data on grasses and revegetation 

 practices in the central and southern Great Plains is a direct out- 

 growth of shifting public sentiment with respect to land use policies 

 in that region. Nearly 50 years ago the United States Department of 

 Agriculture undertook comprehensive studies of these problems and 

 for a few years conducted research which, had it continued, would 

 have yielded an abundance of data of the kind now generally in 

 demand. Unfortunately, however, public interest in cultivated crop 

 culture discouraged grass research and resulted in its discontinuance. 

 Only within the last few years has public sentiment shifted back to 

 grass to a degree that has made possible a renewed research attack 

 upon the problems involved in the regrassing of cultivated farm land 

 and the restoration and maintenance of grass cover on depleted 

 ranges. 



REESTABLISHING PASTURE GRASSES ON CULTIVATED LAND 



Cultivated land may be abandoned farm land, or it may constitute 

 those parts of currently operated farms on which the operators desire 

 to reestablish grass. In either case it is desirable to consider (1) 

 natural and (2) artificial methods of revegetation. 



NATURAL REVEGETATION 



What may be expected from natural revegetation of cultivated land 

 is indicated by the results of a survey made in 1936 3 (60).* During 

 that survey chartographs were made of the basal cover occupied by 

 124 species of grass and 448 species of forbs (weeds), sedges (grass- 

 like plants), and shrubs, on 167 abandoned fields and 138 adjacent 

 virgin pastures, on different textures of soil and under different graz- 

 ing treatments near Woodward. Okla.; Dalhart, Tex.; Tucumcari, 

 N. Mex. ; Springfield. Akron, and Colorado Springs, Colo.; Garden 

 City, Tribune, Hays, and Colby, Kans. ; and North Platte, Nebr. 



The results of that survey show that the length of time required for 

 the more desirable grasses fully to recover abandoned fields varies 

 on the average from 25 to 40 or more years, depending upon environ- 

 mental conditions. These results verify in a large measure previous 

 reports by Shantz (61), Clements (IS), Clements and Chaney (15), 

 and Clarke and Tisclale (1*2). E. W. Nelson, in charge, Department 

 of Range and Pasture Management, Colorado State College, Fort 

 Collins, Colo., recently reported informally that still longer periods 

 were required for the natural reclamation of abandoned land in 

 northeastern Colorado. 



The 1936 survey showed that very few fields reverted to an op- 

 timum stand of the more desirable species in less than 25 years and 

 many required more than 40 years (fig. 1). Although many of the 

 fields were reclaimed with weedy-type grasses early in the stage of 



3 Savage, D. A., and Runyon, H. Everett, important plant species encountered on 



PASTURES AND ABANDONED FARM LAND IN THE CENTRAL AND SOUTHERN GREAT PLAINS IN 



1935 and 1936. U. S. Bur. Plant Indus. Multilith Pub.. 19 pp. 1937. 

 1 Italic numbers in parentheses refer to Literature Cited, p. 50. 



