WRB 2022 Ch 4 (p. 101), Vertisols: other soils having
a vertic horizon starting \<= 100 cm from the mineral soil surface;
\>= 30% clay between the mineral soil surface and the vertic horizon throughout;
shrink-swell cracks that start (a) at the mineral soil surface, (b) at the base of a plough layer, (c) directly below a self-mulching surface (a layer with strong granular, or strong angular or subangular blocky, structure of aggregates \<= 1 cm) or (d) directly below a surface crust, and extend to the vertic horizon.
Since v0.9.311 each item is TRUE, FALSE or NA (not recorded), and the gate
is NA when an item is undecided and none fails. Only a vertic horizon that
can start within 100 cm decides item 1, so unrecorded layers below it do
not leave the gate undecided. Item 3 reads the cracks of each layer as
vertic_horizon does (cracks_width_cm, or slickensides
or an ss designation as evidence of them): every layer between the
start and the vertic horizon must have them, and a layer whose cracks are
not recorded leaves the item undecided. Until v0.9.310 item 3 asked for a
layer with cracks starting within 20 cm and read missing cracks as absent.
Arguments
- pedon
A
PedonRecord.- strict
Logical or
NULL. WhenNULL(default) it resolves viagetOption("soilKey.rsg_strict", FALSE).TRUEapplies the Tier-3 strengthened threshold.