Russian grassland (6)
I believe the answer is:
steppe
'russian grassland' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for steppe that I've seen before include "Dry area of grassland in southeast Europe and Siberia" , "Dry plain of Eurasia" , "Edxtensive plain" , "Dry grassy plain of eastern Europe and Asia" , "Treeless plain of Russia" .)