2. ashy/pumiceous, mesic
Typic Udivitrand
The upper 50 cm of this soil has formed in non-welded ignimbrite from the c. 233 AD Taupo eruption. This material has undergone relatively little weathering and has sandy textures with many pumice fragments. Clay content is generally low, <10%. Underlying horizons to a depth of ~2 m have formed in numerous intermixed tephra layers deposited over the past c. 27,000 years.The dark color of the A horizon is due to shrub-bracken fern vegetation and burning by pre-European Maori (Polynesian) inhabitants since c. 1300 AD.
These soils have low cohesion and are susceptible to erosion. Because of high porosity, they are well suited for sprinkler application and treatment of dairy effluent. This soil is classified as a Buried-allophanic Orthic Pumice Soil in the NZ classification system.
Reference: Prof. D.J. Lowe, Univ. of Waikato, Hamilton, NZ; New Zealand Soil Bureau sample 7669 A-H |
