Final Comprehensive Conservation Plan - U.S. Fish and Wildlife ...

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
Figure 3-1. Soil map of the Hakalau Forest Unit.
Pu‘u ‘O‘o silt loam, 6-12 percent slopes (PUC):
Located on uplands of the windward side of Mauna Kea between 5,000 - 6,500 ft, soils in the Pu‘u
‘O‘o series are gently sloping to moderately steep. The surface layer is dark reddish-brown and very
dark gray silt loam. This layer is approximately 6 in thick and can be strongly acid (pH 5.1 - 5.5) to
very strongly acid (pH 4.5 - 5.0). The subsoil, which is about 21 in thick, is very dark brown to dark
reddish-brown silty clay loam. Material underlying the subsoil is dark yellowish-brown and darkbrown
sandy clay loam. These layers range from strongly acid to extremely acid (pH below 4.5).
Laumai‘a silt loam, 6-20 percent slopes (LAD):
The Laumai‘a series are undulating soils located on high elevations above 5,500 ft of the windward
side of Mauna Kea and are gently sloping to moderately steep. The surface of the Laumai‘a silt loam
is a 12 in thick layer of very dark brown and dark-brown silt loam that is exceptionally stony in
certain areas. The subsoil is roughly double in thickness and is very dark grayish-brown and dark
brown silt loam. The degree of acidity ranges from medium acid (pH 5.6 - 6.0) at the surface layer to
strongly acid at the subsoil.
Hanipoe very stony loam, 12-20 percent slopes (HCD):
The Hanipoe series is found from 5,000 - 6,500 ft in elevation. Hanipoe very stony loam is composed
of a 20-30 in layer over fragmental ‘a‘ā lava.
Chapter 3. Physical Environment 3-5