Dry land reduced to powder (6)
I believe the answer is:
ground
I believe this is a double definition.
'dry land' is the first definition.
(synonyms)
'reduced to powder' is the second definition.
(I've seen this before)
(Other definitions for ground that I've seen before include "See 14" , "The solid surface of the Earth" , "Pulverised; land" , "on which Pachelbel wrote his Canon?" , "crumbled" .)