A verb appearing as G. {bartha- >>} bara- or barna- “dwell in, till (tr.)” in the Gnomish Lexicon of the 1910s (GL/21), clearly derived from the early root ᴱ√MBARA “dwell, live” (QL/63). Its gloss is followed by a parenthentical comment “(land)”. Likely the original sense was “dwell in (a land)”, and from there it gained the sense “✱prepare a land for dwelling” = “till (land), ✱cultivate”.
Neo-Sindarin: Since √MBAR continues to appear in Tolkien’s later writings, for purposes of Neo-Sindarin I would retain transitive ᴺS. barna- “to till (land), ✱cultivate” with an original sense “to dwell in (a land)”. Given this verb’s association with cultivation, however, I would use the later verb [N.] dortha- as the primary verb for “to dwell, stay, settle, ✱live (in a place)” (Ety/NDOR).
A suffixal form of G. brann (GL/24); see S. barthan for discussion.