restricted. A higher level of management is required, such as 

 light, frequent irrigations or more intensive soil conserva- 

 tion and improvement practices (terracing and installation 

 of extensive drainage facilities) than for Class 2 land. Class 

 3 land may be level to strongly sloping. l.and in this class is 

 suitable for irrigation by gravity (0 to 8 percent slopes) or 

 sprinkler methods. 



Class 6 - Nonarable: This land may be steep, dissected, 

 eroded, or may have soils with very poor structure, coarse 

 texture, excess salinity or sodidty, poor drainage, only a 

 shallow thickness over sand and gravel or bedrock, or may 

 have other deficiencies not feasible to improve. Class 6 land 

 may surround areas of Class 1 to Class 3 land which cannot 

 be separated due to the small size of the delineation at the 

 scale used in mapping. 



The arable land class for each mapping unit in the 

 Tongue River and Rosebud Creek areas was determined by 

 using the RWRCC Land Classification Specifications in 

 Appendix D. The soil survey of Rosebud County Area and 

 part of Big Hom County, Montana, completed in 1985 by 

 the Soil Conservation Service, provided the basic data. 

 Descriptions of individual soil mapping units are given in 

 Appendix E. 



B. Arable Lands 



The amount of arable land in the Northern Cheyenne 

 Indian Reservation was calculated for theTongue River and 

 Rosebud Creek areas. TheTongue River part was calculated 

 for three areas: (1) within che seven USGS topographic 

 maps encompassing the Tongue River (Ashland NE, 

 Ashland, Green Ocek, Garfield Peak, Hollowwood Creek, 

 Clubfoot Creek, Bimey Day School), (2) 300 foot vertical 

 lift from theTongue River and (3) 1 00 foot vertical lift from 

 the Tongue River. The Rosebud Oeek area was calculated 

 for the 300 and 1 00 foot vertical lift. The 1 00 foot and 300 

 foot areas were delineated by HKM Associates on its Arable 

 Lands map. Areas in other parts of the reservation were not 



calculated because the amount of water available was not 

 enough to irrigate beyond che 300 foot lift distance from the 

 Tongue River and Rosebud Creek. 



The following acreages were generated by the RWRCC 

 CIS from criteria established by the RWRCC staff. Data 

 used for these calculations were received from SCS and BLA. 



NORTHERN CHEYENNE 

 INDIAN RESERVATION 



Total soil acreage within the reservation = 445,482. 

 Totalsoilacreagewithin 7quadsonTongucrivcr= 130,705. 

 Total soil acreage within 300 foot lift of Tongue river = 

 49,025. 



ARABLE LANDS ANALYSIS 



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