Red spruce (Picea rubens) was historically an important and dominant timber species in the central Appalachian mountain range. The tree species is now found in a small fraction of its original home range. Threatened and endangered organisms such as the Cheat Mountain Salamander (Plethodon nettingi) rely on red spruce associated forests for survival. This review provides a background on the history of forest management of red spruce in the central Appalachian region. A meta-analysis was conducted on recent literature (published 2000 or later) of red spruce in the central Appalachian region to highlight key management and conservation concerns. In particular, forest health concerns related to air pollution and climatic stress also are addressed. Approaches to examine the impact of environmental factors on red spruce site productivity are covered. This review also provides sustainable management options for restoration of red spruce in the central Appalachian mountain range.

Traditional site index curves are frequently produced for shade-intolerant species but are scarce for shade-tolerant species. Red spruce (Picea rubens Sarg.) can be found in three distinct geographic regions (northern, central, and southern) within the Appalachian Mountains. The one commonly used set of red spruce site index curves is over ninety years old. A definite need exists for a modern, regionally applicable set of site index curves. This research sampled 83 plots randomly located in the central Appalachians of West Virginia. Three sets of anamorphic site index curves were created after careful examination of height models built using Chapman-Richards and Meyer functions. One set of curves was constructed with traditional age height pairs. The second utilized a suppression-corrected age and height pair. The third set examined diameter at breast height (DBH) and height pairs. Fit statistics indicated better performance for the suppression-corrected age–height pair site index and the DBH–height pair site index versus the traditional age–height pair models. Site index conversion equations were also investigated for the red spruce age-corrected site index. Linear regression was used to determine significant geographic and climate variables and the utility of including site index values for red maple (Acer rubrum L.) and yellow birch (Betula alleghaniensis Britton) in the model to predict red spruce site index. Significant models were found for varying combinations of species site index, climate, and geographic variables with R2adj in the range of 0.139–0.455. These new site index curves and conversion equations should provide utility for site productivity estimation and growth and yield modeling while aiding in restoration efforts for this important central Appalachian species.

We conducted dendroclimatic analyses and constructed future growth projections for red spruce (Picea rubens Sarg.) throughout the central Appalachians in the state of West Virginia. This study involved field sampling of 18 sites across red spruce’s range throughout Monongahela National Forest in 6 regions based on pairwise combinations of three latitudinal groups (north, central, and southern latitudes) with two aspects (north and south aspect). Each combination of latitudinal group and aspect was referred to as a landscape cluster. Growth was negatively impacted by high summer temperature stress, but responded favorably to high fall temperatures. The results also suggested that red spruce was likely impacted by the degree of winter harshness in all landscape clusters. In the northern latitudinal landscape clusters, red spruce responded favorably to warm spring temperatures by allowing an early start to the growing season. Growth projections under a future climate change scenario show that future expected increases in mean and maximum monthly temperatures will have negative effects on future spruce growth. The forecasting results suggested that red spruce in northern latitudes on south aspects or central latitudes on north aspects are the landscape clusters that will likely be the most resilient to future climate change. Dendroclimatic results and future growth projections can assist with identifying locations that are most suitable for future red spruce restoration activities.

Red spruce (Picea rubens) was historically an important and dominant timber species in the central Appalachian mountain range. The tree species is now found in a small fraction of its original home range. Threatened and endangered organisms such as the Cheat Mountain Salamander (Plethodon nettingi) rely on red spruce associated forests for survival. Recent concerns including air pollution and climate change may threaten the health of remaining red spruce populations.