APPENDIX D 



LAND CAPABILITY CLASSIFICATION 



The capability classification is based on detailed soil surveys 

 which identify each kind of soil and the landscape on which it occurs. 

 The grouping of soils into one of eight different capability classes 

 shows in a general way the soil and landscape most suitable for inten- 

 sive farming. The eight land classes are based on the severity of 

 limitations or hazards in the use of the soil resource and the risk 

 of damage that may occur when not used within their capability and 

 treated according to the needs. 



The capability system provides for three levels of groupings based 

 on the kind of problem related to land use and management needs of the 

 soil resource. They are the capability class, commonly shown by roman 

 numerals I through VIII; subclass is shown by small letters e, w, s, and 

 c, which identify the major kind of problem such as erosion, wetness, 

 soil and climate; the capability unit groups similar kinds of soils at 

 each subclass that have about the same production capacity and will 

 respond to similar systems of management for a particular kind of use. 

 Only the capability class and subclass groupings were used in this 

 inventory to identify land use and treatment needs. 



LAND SUITED FOR CULTIVATION AND OTHER USES 

 Class I 



Lands in class I have few limitations that restrict their use. Soils 

 in this class are suited to a wide range of plants and may be used safely 

 for cultivated crops, pasture, woodland and wildlife. The soils are 

 nearly level and erosion hazard is low. They are deep, well drained, and 

 easily worked. They hold water well and are either fairly well supplied 

 with plant nutrients or highly responsive to inputs of fertilizer. 



The soils in class I are not subject to damaging overflow. They are 

 productive and suited for intensive cropping. The local climate must be 

 favorable for growing many of the common field crops, including corn. 



Soils that are wet and have slowly or very slowly permeable subsoils 

 are not placed in class I. Soils in class I that are used for crops need 

 ordinary management practices to maintain soil fertility and soil structure. 

 For productivity such practices may include the use of one or more of the 

 following: fertilizers, green-manure crops, conservation of crop residues 

 and animal manures and sequences of adapted crops. Because of unfavorable 

 climate, such as low rainfall or short growing season, only irrigated lands 

 qualify for class I in Montana. 



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