Here's some dictionary help at least (with some etymology)...

Often, downs. (used especially in southern England) open, rolling, upland country with fairly smooth slopes usually covered with grass. Archaic: a hill, especially a sand hill or dune. Middle English; Old English dūn hill; cognate with Dutch duin dune

Wold 'high, open, uncultivated land' (according to Tolkien scholars Hammond and Scull) or 'a usually upland area of open country', capitalized 'hilly or rolling region' (Webster). This word is interesting as it appears related to certain forest related words...

Wold (online source)

O.E. wald (Anglian), weald (W.Saxon, Kentish) "forest, wooded upland," from P.Gmc. *walthuz [cf. O.S., O.Fris. wald, M.Du. wold, Du. woud, O.H.G. wald, Ger. Wald "forest," Swed. vall "pasture," O.N. völlr "soil, field, meadow"]; perhaps connected to wild. The sense development from "forested upland" to "rolling open country" (c.1200) perhaps is from Scandinavian influence, or a testimony to the historical deforestation of Britain. Not current since mid-16c.; survives mainly in place names (cf. Cotswold).

My Anglo-Saxon dictionary notes that 'wold = weald', seemingly implying that the sense was equivalent enough in certain old sources anyway. /.  , implying that at this point the se