At Big Run Bog, a Sphagnum-dominated wetland in the Appalachian Mountains of West Virginia, annual aboveground net primary production (NPP) was estimated to be 1045 g/m2. Bryophytes, herbaceous species, trailing shrubs, and upright shrubs contributed 43, 20, 10, and 27%, respectively, to the total aboveground NPP, while area-weighted mean percent cover for these 4 groups was 68, 42, 43, and 21%, respectively. Compared to estimates of aboveground NPP reported for more northern bog ecosystems, our value for Big Run Bog is relatively high, probably reflecting the higher temperatures and longer growing season in this relatively southern peatland.