Run away from infertile area (6)
I believe the answer is:
desert
This clue is a triple definition!
'run away from' is the first definition.
(thesaurus)
'infertile' is the second definition.
(thesaurus)
'area' is the third definition.
(desert is a kind of area)
(Other definitions for desert that I've seen before include "Walk out on" , "Defect, forsake" , "Wild" , "Kalahari, for example" , "Treacherously abandon" .)