Natural Resources
Conservation Service
Ecological site F130AY006PA
Quartzitic Footslopes And Terraces
Last updated: 9/27/2024
Accessed: 11/13/2024
General information
Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.
MLRA notes
Major Land Resource Area (MLRA): 130A–Northern Blue Ridge
Major Land Resource Area 130A is in the Northern Section of the Blue Ridge Province of the Appalachian Highlands. The region is characterized by rugged mountains with steep slopes, sharp crests, and narrow valleys. The mountain range forms a narrow band that runs north to south between the Piedmont Upland Section to the east, the Ridge and Valley section to the west, and the Southern Section of the Blue Ridge to the south. Stream dissection is deep and intricate. Major streams and their tributaries flow through gorges and gaps. Elevation ranges from about 820 feet (250 meters) in the lower valleys and on footslopes along the Potomac River just east of Harpers Ferry, where West Virginia joins Maryland and Virginia, to more than 4,200 feet (1,280 meters) along the Appalachian Trail in Bedford County, Virginia. Apple Orchard Mountain, the highest peak, is at an elevation of 4,225 feet (1,288 meters) (USDA 2006).
The backbone of the northern Blue Ridge is an anticline composed of rocks that can be can be divided into geological groupings based on age. In general, the oldest rocks are the furthest east, and become younger towards the west (Fichter and Baedke, 2000; Barnes and Sevon, 2002). The first group are plutonic rocks that formed when liquid molten rock, called magma, solidified deep within the earth’s crust over a billion years ago. Collectively referred to as the Grenville rocks, they make up much of the eastern half of the mountains and are composed of granites, gneisses, and granulites. The second group, characterized by the Catoctin greenstone formation, is slightly younger, and is made up of metabasalts and metarhyolites, types of igneous rocks that have been metamorphosed by heat and pressure. The third group was formed during the Cambrian period about 500 million years ago and are represented by the Harpers, Antiedam, Weverton, and Loudoun formations which comprise the Chilhowee group. These rocks are primariliy quartzites, phyllites, and meta-sandstones, and form the western flank of the Blue Ridge.
Preliminary ecological site differentiation is based on these three main age groups and geologies. The variable characteristics of the underlying rocks give rise to different soil physical and chemical properties and exert control on the landscape, slope shape, aspect, and elevation, all of which affect vegetation.
Classification relationships
This ecological site is found in Major Land Resource Area 130A – the Northern Blue Ridge. MLRA 130A is located within Land Resource Region N – East and Central Farming and Forest Region (USDA 2006), and in United States Forest Service ecoregion M221D – Central Appalachian Broadleaf Forest-Coniferous Forest-Meadow Province, Blue Ridge Mountain Province (Bailey, 1995).In addition, MLRA 130A falls within area #66 of EPA Ecoregion Level III – the Blue Ridge (US EPA 2013). The Quartzitic Footslopes and Terraces ecological site occurs primarily within 66b of EPA Ecoregion IV – Northern Sedimentary and Metasedimentary Ridges (Woods et. al., 1996).
Central Appalachian Dry Oak-Pine Forest System - CES202.591
Quercus prinus - (Quercus coccinea, Quercus rubra) / Kalmia latifolia / Vaccinium pallidum Forest Association (CEGL006299)
Northeastern Interior Dry-Mesic Oak Forest System - CES202.592
Quercus prinus - Quercus rubra / Hamamelis virginiana Forest Association (CEGL006057)
(NatureServe 2017)
Ecological site concept
The Quartzitic Footslopes and Terraces ecological sites are located in the Northern Blue Ridge region of the Appalachian Highlands, primarily on the western side where underlying geologies are mostly composed of quartzite, metaquartzite, phyllite, sandstone, and shale. This ecological site is found on lower mountain slopes, footslopes, toeslopes, coves, benches, drainageways, mountain valleys, stream terraces, and fans. Soils are deep, well drained and very strongly to moderately acidic. Low to mid slope areas generally have more moisture than ecological sites further upslope, however, these landscapes are dry due to the sandy soil textures and stoniness. This ecological site is drier, more acidic, and less fertile than the Mixed Metamorphic-Metabasalt Footslopes and Terraces ecological site which is on similar landscapes, but underlain by different geology: metabasalts, granitic rocks, granodiorite, gneiss, schists, and some phyllite.
Not much is known about this site, and future field work may result in it being combined with another coarse textured terrace or floodplain ecological site or combined with an upland site. Current field data from the Heritage Programs of Pennsylvania, Maryland, and Virginia suggest that this ecological site is very similar to the Quartzitic Uplands, however, much more ruderal forest exists on these lower slope areas than in the upper slopes and ridgetops, suggesting a more extensive history of logging, past farming and settlement. The reference state is a combination of several vegetation communities within the Central Appalachian Dry Oak-Pine Forest, and the Northeastern Interior Dry-Mesic Oak Forest as defined by NatureServe (NatureServe 2009). These forests are mostly closed-canopy but can include patches of more open woodlands and grasslands. The coarse, acidic, well drained soils, will host a variable mixture of dry-site oak and pine species. Heath shrubs are common in the understory.
Associated sites
F130AY004PA |
Quartzitic Upland The Quartzitic Upland occurs on adjacent upper slopes. |
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F130AY007PA |
Fine To Loamy Mixed Metamorphic Floodplain The Fine to Loamy Mixed Metamorphic Floodplain occurs along adjacent drainageways and streams. |
Similar sites
F147XY007PA |
Loamy To Coarse Terrace The Loamy to Coarse Terrace provisional ecological site of the Ridge and Valley major land resource area has similar soil textures, depth, and drainage. Future field work and analysis may result in these ecological sites being combined. |
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F130AY004PA |
Quartzitic Upland The Quartzitic Upland provisional ecological site of the Northern Blue Ridge is similar but is generally drier with many more areas of shallow soils. More fieldwork is needed to see if these ecological sites should be combined. |
Table 1. Dominant plant species
Tree |
(1) Quercus prinus |
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Shrub |
(1) Kalmia latifolia |
Herbaceous |
Not specified |
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