* limited to sites with higher soil calcium
Vascular plant nomenclature follows Rhoads and Block (2007). Bryophyte nomenclature follows Crum and Anderson (1981).

International Vegetation Classification Associations:

USNVC Crosswalk:

None

Representative Community Types:

Central Appalachian Pine - Oak / Heath Woodland (CEGL004996)

NatureServe Ecological Systems:

None

NatureServe Group Level:

Central Appalachian - Northeast Pine - Oak Rocky Woodland (G906)

Origin of Concept

Fike, J. 1999. Terrestrial and palustrine plant communities of Pennsylvania. Pennsylvania Natural Diversity Inventory. Pennsylvania Department of Conservation and Recreation, Bureau of Forestry, Harrisburg, PA. 86 pp.

Fleming, G. P. and P. P. Coulling. 2010. Central Appalachian Pine - Oak / Heath Woodland (CEGL004996). NatureServe Explorer [web application]. NatureServe, Arlington, Virginia. Available https://explorer.natureserve.org/. (Accessed: January 6, 2022).

Pennsylvania Community Code*

JF : Pitch Pine - Heath Woodland

*(DCNR 1999, Stone 2006)

Similar Ecological Communities

Within Pennsylvania, the Pitch Pine – Heath Woodland is also a dry woodland type found on acidic summits, but lacks red spruce, and has a greater dominance of pitch pine and in some cases, also has a minor component of oaks in the canopy. A history of fire may be more important for the Pitch Pine – Heath Woodland type, while a northern aspect/cool microclimate may be more important for the Red Spruce Rocky Summit. The Pennsylvania example of this community type lacks the fir component of spruce balds found at high elevations both farther north in the Adirondacks (balsam fir), and farther south in the Blue Ridge (Fraser fir) North of Pennsylvania, the floristically similar Red Spruce Talus Slope Woodland (CEGL006250) occurs on talus, while the Red Spruce Rocky Summit is found on bedrock ridges and outcrops.

Fike Crosswalk

Pitch Pine - Heath Woodland

Conservation Value

Acidic barrens communities can host a number of rare plant species and an exceptional diversity of rare butterflies, moths, and other insects. Barrens communities can arise as a result of a variety of human-induced and natural disturbances; many have their origin in the 19th or 20th century, while others have persisted longer through a combination of periodic human-induced disturbance dating to pre-settlement times and edaphic factors (Copenheaver et al., 2000; Kurczewski, 1999; Latham, 2003; Motzkin & Foster, 2002). Latham (2003) suggests that the diversity and presence of rare plant species in barrens is correlated with the overall age of the barrens, with newer barrens less likely to host rare plants. Animal diversity appears to be less sensitive to age; perhaps because many of these species are highly mobile. Both plant and lepidopteran species can be sensitive to successional stage and time since disturbance; some require very open, grassy areas, while others can also inhabit shrublands and woodlands with partial shade. The species of conservation value are not necessarily indicator species for the community type, and may also occupy other types of habitat, but barrens sites are one of the habitats important for their conservation. Species of great conservation value that are associated with barrens include many species of Lepidoptera (moths and butterflies) which have barrens plants as hosts, plants that can withstand the acidic, thin soils, and vertebrate species who thrive with hot, dry conditions. Examples of invertebrates that can be found in barrens include waxed sallow moth (Chaetaglaea cerata; G3G4/S2S3), twilight moth (Lycia rachelae; G5/S2?), and flypoison borer moth (Papaipema sp. 1; G2G3/S2S3). The timber rattlesnake (Crotalus horridus; G4/S2S3) and eastern hognose snake (Heterodon platirhinos; G5/S3S4) can utilize barrens. A few plant species that are associated with barrens include variable sedge (Carex polymorpha; G3/S2), dwarf iris (Iris verna; G5/S1), and sand blackberry (Rubus cuneifolius; G5/S1).

Threats

The primary threats to acidic barrens communities are succession and fire suppression. Many of the unique species that inhabit these barrens are most successful in the early stages of succession, such as grasslands and open shrublands, and are therefore particularly vulnerable to the effects of succession over the long-term. Pitch pine are known to not germinate and establish well without fire. Spongy moth (Lymantria dispar) outbreaks also threaten barrens, which often have a strong component of oak species in the tree and shrub layers. However, spongy moth control agents can also threaten the unique butterfly and moth species that inhabit barrens. Studies across a number of sites in New England and Pennsylvania demonstrate that many barrens are disturbance-dependent ecosystems that, in the absence of disturbance, move through succession to forest rapidly (Copenheaver et al., 2000; Kurczewski, 1999; Latham, 2003; Motzkin & Foster, 2002). These studies have observed similar patterns of barrens succession to forest, sometimes even mesic forest, in recent decades. Changes in land use and fire suppression over the last century are at the root of these patterns of succession. Through meticulous efforts to identify historic land use and changes in vegetation over time, researchers have documented that barrens are correlated with areas that burned frequently; primarily from Native American use of fire and railroads. The cessation of these land use practices, and the advent of widespread, long-term fire suppression, is correlated with succession of grasslands and open shrublands to dense shrub thickets and forests. Charcoal production retards vegetation such that former hearths resemble barrens, but it appears the mechanism is a more profound and persistent alteration of soil chemistry. The Pitch Pine – Heath Woodland is also threatened by the southern pine beetle (Dendroctonus frontalis). The southern pine beetle is a native beetle of the southeastern United States that feeds primarily on pines such as pitch, shortleaf, Virginia, and white. Outbreaks occur every 6-12 years and can last for 2-3 years. The southern pine beetle feeds on phloem in the inner bark, which ultimately girdles and kills the tree (Liu, n.d.). Additionally, the southern pine beetle has experienced an unprecedented northward expansion in recent years due to mild winters and climate models predict the range to expand to almost the entirety of Pennsylvania (aside from much of the Northern Allegheny Plateau) by 2050, and north into Canada by 2080 (Lesk et al., 2017). The southern pine beetle does not currently overlap with the native range of this community type, however it is considered a serious long-term threat. This community type may also be impacted by the spotted lanternfly (Lycorma delicatula). The spotted lanternfly is newly established in Pennsylvania and has been found to lay eggs and feed on a number of common hardwood trees in Pennsylvania, but has not been found to cause tree mortality (Barringer & Ciafré, 2020). This invasive pest may weaken hardwood associate trees in this type but may only represent a small threat since hardwood trees are not dominant. Other threats include loss of this community due to development of cell phone towers, wind turbines, and utility lines, or trampling by visitors on ATVs.

Management

It is important to develop a site-wide management plan at acidic barrens to maintain multiple successional stages. Fire is the optimal tool for barrens management. Where it is not feasible to use fire as a management tool, a combination of cutting and soil scarification can be used to mimic its effects. Plans should also consider specific needs of barrens indicator species and rare species. To avoid severe reduction of lepidopteran populations, prescribed burning should not be undertaken across an entire site at once; in a given year, unburned areas should be left as refugia for these species. Spongy moth control programs should balance maintenance of oaks and lepidopterans, using control agents specific to the spongy moth where possible, or leaving some untreated areas as refugia for native lepidopteran populations.

Range Map

Pennsylvania Range

The Pitch Pine - Heath Woodland is found in the following USEPA Level III (IV) Ecoregions: Northern Central Appalachians (62) and Ridge and Valley (67).

Global Distribution

Maryland, Pennsylvania, Virginia, West Virginia

Barringer, L., & Ciafré, C. M. (2020). Worldwide feeding host plants of spotted lanternfly, with significant additions from North America. Environmental Entomology, 49(5), 999–1011.

Copenheaver, C. A., White, A. S., & William A. Patterson III. (2000). Vegetation Development in a Southern Maine Pitch Pine-Scrub Oak Barren. Journal of the Torrey Botanical Society, 127(1), 19–32.

Illick, J. S., and Aughanbaugh, J. E. 1930. Pitch pine in Pennsylvania. Pa. Dept. Forests and Waters Res. Bul. 2.

Kurczewski, F. E. (1999). Historic and Prehistoric Changes in the Rome, New York Pine Barrens. Northeastern Naturalist, 6(4), 327–340.

Latham, R. E. (2003). Shrubland longevity and rare plant species in the northeastern United States. Forest Ecology and Management, 185(1–2), 21–39.

Lesk, C., Coffel, E., D’Amato, A. W., Dodds, K., & Horton, R. (2017). Threats to North American forests from southern pine beetle with warming winters. Nature Climate Change, 7, 713–717. https://doi.org/10.1038/nclimate3375

Liu, H. (n.d.). Southern Pine Beetle: Forest Insects& Diseases Fact Sheet. Pennsylvania Department of Conservation and Natural Resources, Bureau of Forestry, Division of Forest Health.

Motzkin, G., & Foster, D. R. (2002). Grasslands, heathlands and shrublands in coastal New England: Historical interpretations and approaches to conservation. Journal of Biogeography, 29(10–11), 1569–1590.

Ordnorff, S., & Patten, T. (Eds.). (2007). Management Guidelines for Barrens Communities in Pennsylvania (p. 208). The Nature Conservancy.

Schweitzer, D.F. & Rawinski, T.J. (1987) Northeastern pitch pine ⁄ scrub oak barrens. Eastern heritage task force. The Nature Conservancy, Boston, MA.