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DC.Torrands

Key to Suborders 

DC. Other Andisols that have an aridic moisture regime. Torrands, p. 294 

DC. Torrands are the more or less well drained Andisols of dry regions. These soils are not extensive. Some formed in the western part of North America, and some are known to occur in Hawaii and other Pacific islands. Most of the soils formed under grassy or shrub vegetation. Characteristically, Torrands have an ochric or mollic epipedon and a cambic horizon. Some have a duripan or a petrocalcic horizon. The Torrands in the United States generally developed in late-Pleistocene or Holocene deposits. 

Definition 

Torrands are the Andisols that:

1. Have an aridic soil moisture regime;

2. Have a frigid or warmer soil temperature regime; and

3. Do not have a histic epipedon or the aquic conditions characteristic of Aquands. 

Key to Great Groups 

DCA. Torrands that have, in 75 percent or more of each pedon, a cemented horizon that has its upper boundary within 100 cm either of the mineral soil surface or of the top of an organic layer with andic soil properties, whichever is shallower. Duritorrands, p. 294 

DCB. Other Torrands that have, on air-dried samples, a 1500 kPa water retention of less than 15 percent throughout 60 percent or more of the thickness either:

1. Within 60 cm either of the mineral soil surface or of the top of an organic layer with andic soil properties, whichever is shallower, if there is no densic, lithic, or paralithic contact, duripan, or petrocalcic horizon within that depth; or

2. Between either the mineral soil surface or the top of an organic layer with andic soil properties, whichever is shallower, and a densic, lithic, or paralithic contact, a duripan, or a petrocalcic horizon. Vitritorrands, p. 296 

DCC. Other Torrands. Haplotorrands, p. 295

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