Horizon Depth

UDEPTH           Upper horizon depth (cm).
LDEPTH           Lower horizon depth (cm).

     UDEPTH must be less than LDEPTH.
 
     If KIND=M (mineral soils)
        UDEPTH must be   0 to  999 for mineral layers.
        UDEPTH must be -50 to   1 for organic layers.
        LDEPTH must be   1 to  999 for mineral layers.
        LDEPTH must be -49 to   0 for organic layers.
       

     If KIND=O (organic soils)
        UDEPTH must be  40 to 999 for mineral layers.
        UDEPTH must be   0 to 999 for organic layers.
        LDEPTH must be  41 to 999 for mineral layers.
        LDEPTH must be   1 to 999 for organic layers.