Those formed by the decay of limestone and calcareous shale (as in the Blue Grass region) are almost always fertile;
(Those; formed; by the decay of limestone and calcareous shale (as in the Blue Grass region) (Those formed by the decay of limestone and calcareous shale (as in the Blue Grass region; are; T:almost always; fertile)
Those Those formed by the decay of limestone and calcareous shale (as in the Blue Grass region
formed are
by the decay of limestone and calcareous shale (as in the Blue Grass region
T:almost always fertile