American Wintergreen (Gaultheria procumbens), a.k.a Eastern Teaberry has flowers like blueberry [see Newcomb's p. 212]; the exact habitat was not recorded, but it was either field, field-edge or woods (the edible-plants field trip crossed a field and entered a woods just north of Camp Allegany); photo ref. = Wintergreen_ANP_©DaveSpier_D081109iN
I doubt this is Partridgeberry (Mitchella repens) which has leaves with untoothed edges and a double-flower bud [see Newcomb's p. 156]; for Partridgeberry photos see http://www.inaturalist.org/observations/527999 and http://www.inaturalist.org/observations/528572
Gaultheria procumbens (eastern teaberry, checkerberry, boxberry, or American wintergreen) is a species of Gaultheria native to northeastern North America from Newfoundland west to southeastern Manitoba, and south to Alabama. It is a member of the Ericaceae (heath family).