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

 not placed in Class I. Some kinds of soil in Class I may be drained as 

 an improvement measure for increased production and ease of operation. 



Soils in Class I that are used for crops need ordinary management prac- 

 tices to maintain productivity — both soil fertility and soil structure. 

 Such practices may include the use of one or more of the following: Fer- 

 tilizers and lime, cover and green-manure crops , conservation of crop 

 residues and animal manures, and sequences of adapted crops. 



Class II . — Soils in Class II have some limitations that reduce the choice 

 of plants or require moderate conservation practices. 



Soils in this class require careful soil management, including conserva- 

 tion practices, to prevent deterioration or to improve air and water re- 

 lations when the soils are cultivated. The limitations are few and the 

 practices are easy to apply. The soils may be used for cultivated crops, 

 pasture, range, woodland, or for wildlife food and cover. 



Limitations of soils in Class II may include singly or in combination the 

 effects of (1) gentle slopes? (2) moderate susceptibility to wind or water 

 erosion, or moderate adverse effects of past erosion; (3) less than ideal 

 soil depth; (4.) somewhat unfavorable soil structure and workability; (5) 

 slight to moderate salinity or alkalinity, easily corrected but likely to 

 recur; (6) occasional damaging overflow; (7) wetness correctible by drain- 

 age but existing permanently as a moderate limitation; and (8) slight 

 climatic limitations on soil use and management. 



The soils in this class provide the farm operator less latitude in the 

 choice of either crops or management practices than soils in Class I. 

 They may also require special soil -conserving cropping systems, soil con- 

 servation practices, water-control devices, or tillage methods when used 

 for cultivated crops. For example, deep soils of this class with gentle 

 slopes that are subject to moderate erosion when cultivated may need one 

 of the following practices or some combination of two or mores terrac- 

 ing, stripcropping, contour tillage, crop rotations that include grasses 

 and legumes, vegetated water-disposal areasj, cover on green-manure crops, 

 stubble mulching, fertilizers, manure, and lime. The exact combinations 

 of practices vary from place to place, depending on the characteristics 

 of the soil, the local climatej, and the farming system. 



Class III . — Soils in Class III have severe limitations that reduce the 

 choice of plants or require special conservation practices, or both. 



Soils in Class III have more restrictions than those in Class II, and 

 when used for cultivated crops, the conservation practices are usually 

 more difficult to apply and maintain. They may be used for cultivated 

 crops, pasture, woodland, range, or for wildlife food and cover. 



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