In this chapter, we review and synthesize the literature on the dynamics of central and southern Appalachian red spruce (Picea rubensRed spruce ()) and spruce-fir forests under five topics. We begin with gap dynamics in old-growth forests by describing the natural dynamics and the contrasting strategies of the major tree species: red spruceRed spruce (), Fraser fir (Abies fraseri), yellow birch (Betula alleghaniensis), and pin cherry (Prunus pensylvanica). We then discuss four topics that address human impacts on these dynamics: broad-scale logging and remnant old-growth forests; the balsam woolly adelgidBalsam woolly adelgid (Adelges piceae); pollutant deposition and exposure; and climate changeClimate change. We also discuss potential interactions among these disturbancesDisturbance. In general, ecosystem dynamics are driven by red spruceRed spruce ()’s high shade tolerance, long life span, and small canopy gapsCanopy gap due to mortality of individual or small groups of trees. Forests in the southern Appalachians have the additional disturbanceDisturbance dynamic of mortality from balsam woolly adelgidBalsam woolly adelgid. While silvicultural prescriptions for commercial management of spruce-dominated forests are in use in forests in New England and Canada, demonstrated success for commercial scale management is currently lacking for the central and southern Appalachians.