For contests, the subsoil texture sample in the box will be used to determine the permeability. Subsoil texture and structure are of primary importance in determining permeability. Four levels of permeability are recognized in Oklahoma land judging. Subsoils tend to be very friable or loose when moist, and exhibit little restriction of water or air. They are friable to very friable with large pores.
Roots are abundant.
A few soils with moderately fine texture and granular subsoils, are also moderately permeable. For contest, the subsoil texture sample in the box will be used to determine the permeability. Soils that have moderately fine-textured subsoils with angular and subangular blocky structure are slowly permeable. The subsoils are firm when moist and hard when dry. Roots are common.