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SOIL INTERPRETATIONS FOR AGRICULTUREAgricultural Capability Classification for Common Field Crops(1) Capability classification for mineral soilsThe Canada Land Inventory classification system of land capability for agriculture isdescribed in CLI Report No . 2 (14) . It groups mineral soils into seven classes according to theirpotential and limitation for agricultural use for common field crops . Common field crops includecorn, oats, wheat, barley and perennial forage crops such as alfalfa, grasses and birdsfoot trefoil.Crops such as canola, potatoes, fruits and vegetables are not covered by this classification .The best soils, with no significant limitations for crop use, are designated Class 1 . Soilsdesignated Classes 2 to 6 have decreasing capability for agriculture, and Class 7 soils have noagricultural potential. A brief outline of each agricultural capability class follows .Soil Capability ClassesClass 1 - Soils in this class have no significant limitations in use for crops . These soilsare level to very gently sloping, deep, well- to imperfectly drained, and hold moisture and plantnutrients well . They can be managed and cropped without difficulty. Under good management theyare moderately high to high in productivity for common field crops .Class 2 - Soils in this class have moderate limitations that restrict the range of crops, orrequire moderate conservation practices. These soils are deep, and may not hold moisture andnutrients as well as Class 1 soils. The limitations are moderate, and the soils can be managed andcropped with little difficulty. Under good management, they are moderately high to high inproductivity for common field crops.Class 3 - Soils in this class have moderately severe limitations that restrict the range ofcrops, or require special conservation practices . The limitations are more severe than for Class2 soils. They affect one or more of the following practices: timing and ease of tillage ; planting andharvesting; choice of crops ; and methods of conservation . Under good management, they are fairto moderately high in productivity for common field crops .Class 4 - Soils in this class have severe limitations that restrict the range of crops orrequire special conservation measures, or both . The limitations sery _` :}iy affect one or more of thefollowing practices : timing and ease of tillage ; planting and harvesting ; choice of crops ; and methodsof conservation . The soils are low to fair in productivity for common field crops, but may havehigher productivity for a specially adapted crop .Class 5 - Soils in this class have very severe limitations that restrict their capability toproduce perennial forage crops, and improvement practices are feasible . The limitations are sosevere that the .soils are not capable of use for sustained production of annual field crops. The soilsare capable of producing native or tame species of perennial forage plants, and may be improvedby use of farm machinery. The improvement practices may include clearing brush, cultivating,seeding, fertilizing or water control .