Pitch Pine - Heath Woodland
System: Terrestrial
Subsystem: Woodland
PA Ecological Group(s):
Southern Appalachian Virginia Pine – Table Mountain Pine Woodland
Global Rank:G4
rank interpretation
State Rank: S2
General Description
This is a woodland community type that occurs on rocky ridgetops, sandy soils, or both. Soils for this community are acidic and conditions are dry. This community may occur on ridgetop acidic barrens sites that are associated with other acidic barrens communities. Trees are drought-stressed and of small stature. Pitch pine (Pinus rigida) is usually the dominant tree, although in southern Pennsylvania, Virginia pine (P. virginiana), and table-mountain pine (P. pungens) may accompany or replace pitch pine. Red pine (P. resinosa) may also occur on some sites. Hardwoods may be present but do not contribute more than 25% of the tree layer. Hardwood associates include blackgum (Nyssa sylvatica), sassafras (Sassafras albidum), sweet birch (Betula lenta), chestnut oak (Quercus montana), scarlet oak (Q. coccinea), black oak (Q. velutina), gray birch (B. populifolia), and red maple (Acer rubrum). Eastern white pine (Pinus strobus) may also occur but is not common. Various shrubs, mostly heaths, form a low shrub layer. Characteristic species include black huckleberry (Gaylussacia baccata), low sweet blueberry (Vaccinium angustifolium), low-bush blueberry (V. pallidum), sweet fern (Comptonia peregrina), black chokeberry (Aronia melanocarpa), sheep laurel (Kalmia angustifolia) and teaberry (Gaultheria procumbens). Scrub oak may be scattered but is not dominant. Herbaceous species include bracken fern (Pteridium aquilinum), common hair-grass (Deschampsia flexuosa), poverty grass (Danthonia spicata), cow-wheat (Melampyrum lineare), Pennsylvania sedge (Carex pensylvanica), a sedge (C. communis), wild sarsaparilla (Aralia nudicaulis), little bluestem (Schizachyrium scoparium) and bush clovers (Lespedeza spp.).
Rank Justification
This type is uncommon and is potentially under-surveyed. The Pitch Pine – Heath Woodland may be threatened with forest succession due to a lack of fire. Continued fire suppression will prevent pitch pine regeneration and increase hardwood cover in this community type.
Identification
- Occurs on dry, sandy, acidic soils
- Total tree canopy cover is between 10% - 60%
- Pitch pine cover is 25-75%, with hardwood cover less than 25%
- Shrub layer is mainly composed of heath shrub species
Trees
- Pitch pine (Pinus rigida)
- Table-mountain pine (Pinus pungens)
- Norway pine (Pinus resinosa)
- Chestnut oak (Quercus pinus)
- Scarlet oak (Quercus coccinea)
- Black oak (Quercus velutina)
- Blackgum (Nyssa sylvatica)
- Sassafras (Sassafras albidum)
- Black birch (Betula lenta)
- Gray birch (Betula populifolia)
- Red maple (Acer rubrum)
Shrubs
- Scrub oak (Quercus ilicifolia)
- Low sweet blueberry (Vaccinium angustifolium)
- Lowbush blueberry (Vaccinium pallidum)
- Sweet-fern (Comptonia peregrina)
- Black huckleberry (Gaylussacia baccata)
- Mountain laurel (Kalmia latifolia)
- Highbush blueberry (Vaccinium corymbosum)
- Black chokeberry (Aronia melanocarpa)
- Bog laurel (Kalmia polifolia)
- Teaberry (Gaultheria procumbens)
Herbs
- Northern bracken fern (Pteridium aquilinum)
- Common hairgrass (Deschampsia flexuosa)
- Poverty-grass (Danthonia spicata)
- Little bluestem (Schizachyrium scoparium var. scoparium)
- Trailing-arbutus (Epigaea repens)
- Cow-wheat (Melampyrum lineare var. americanum)
- Sedge (Carex pensylvanica)
- Sedge (Carex communis)
- Wild sarsaparilla (Aralia nudicaulis)
- Bush Clovers (Lespedeza spp.)
* 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.
Research Needs
Site-specific research into historical land management, fire frequency, and vegetation patterns has greatly enhanced understanding of barrens systems at other locations in the northeastern region, but very few Pennsylvania sites have been studied. The origins and timeline of many of our barrens sites in Pennsylvania remains unknown. There is a need to adapt and/or develop management techniques specialized to this region and its species of concern. In some areas, barrens have completely succeeded to forest. Research should focus on identifying specifically where shrub and herbaceous barrens once existed, identifying characteristics of optimal restoration sites, and identifying successful management techniques for restoring the herbaceous and shrub component of barrens mosaics.
Trends
Barrens ecosystems have declined due to succession and fire suppression in recent decades. Rare species that are particularly dependent on open barrens habitats have also declined across Pennsylvania.
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.
Cite as:
Braund, J., E. Zimmerman, A. Hnatkovich, and J. McPherson. 2022. Pennsylvania Natural Heritage Program. Pitch Pine - Heath Woodland Factsheet. Available from: https://naturalheritage.state.pa.us/Community.aspx?=16095 Date Accessed: October 10, 2024