(b) A water table at less than 1.5 ft from the surface 

 for a significant period (usually a week or more) 

 during the growing season if permeability is less 

 than 6.0 in/hr in any layer within 20 inches; or 



c. Soils that are ponded for long or very long duration during the 

 growing season; or 



d. Soils that are frequently flooded for long duration or very 

 long duration during the growing season." 



A hydric soil may be either drained or undrained, and a drained hydric soil 

 may not continue to support hydrophytic vegetation. Therefore, not all areas 

 having hydric soils will qualify as wetlands. Only when a hydric soil sup- 

 ports hydrophytic vegetation and the area has indicators of wetland hydrology 

 may the soil be referred to as a "wetland" soil. 



38. A drained hydric soil is one in which sufficient ground or surface 

 water has been removed by artificial means such that the area will no longer 

 support hydrophyte vegetation. Onsite evidence of drained soils includes: 



a. Presence of ditches or canals of sufficient depth to lower the 

 water table below the major portion of the root zone of the 

 prevalent vegetation. 



b. Presence of dikes, levees, or similar structures that obstruct 

 normal inundation of an area. 



c. Presence of a tile system to promote subsurface drainage. 



d. Diversion of upland surface runoff from an area. 

 Although it is important to record such evidence of drainage of an area, a 

 hydric soil that has been drained or partially drained still allows the soil 

 parameter to be met. However, the area will not qualify as a wetland if the 

 degree of drainage has been sufficient to preclude the presence of either 

 hydrophytic vegetation or a hydrologic regime that occurs in wetlands. NOTE: 

 the mere presence of drainage structures in an area is not sufficient basis 

 for concluding that a hydric soil has been drained; such areas may continue to 

 have wetland hydrology . 



General information 



39. Soils consist of unconsolidated, natural material that supports, or 

 is capable of supporting, plant life. The upper limit is air and the lower 

 limit is either bedrock or the limit of biological activity. Some soils have 

 very little organic matter (mineral soils) , while others are composed pri- 

 marily of organic matter (Histosols) . The relative proportions of particles 

 (sand, silt, clay, and organic matter) in a soil are influenced by many 



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