This key is provided for the land cover classes depicted on the map.  In each case, "dominant" is used to describe a species (or groups of species) that occupy 60% or more of the area.  Only those species that may comprise a significant part of the vegetation are given.  The vegetated landscape of Virginia is extremely complex and diverse, and many other species may be found in addition to those mentioned below.

Montane Mesic Conifer (code 1)

This class consists of coniferous forests in the Appalachian Mountains typically found in high elevation, flat areas.  Typical dominant trees are Pinus strobus, Tsuga
canadensis, and Pinus virginiana.  Picea rubens and Abies fraseri are may be found at the highest altitudes (> 5,000 feet).

Montane Xeric Conifer (code 2)

This class consists of predominantly coniferous forests found on steeper slopes, dry areas, and in plantations.  The dominant species is Pinus virginiana, other
associates include Pinus pungens, Pinus strobus, and Pinus rigida.

Red Spruce/Fraser Fir (code 3)

There a few remaining high-elevation spruce/fir forests in Virginia.  They are for the most part restricted to high mountains such as Mt. Rogers and Beartown Mountain.  Picea rubens and Abies fraseri are found both in pure stands and mixed with each other.

Submontane Yellow Pine (code 4)

This class is dominated by both naturally occurring and planted Pinus taeda.  In some parts of the Piedmont, Pinus virginiana and Pinus echinata also occur in both
mixed and pure stands.  Pinus palustris occurs in very small, isolated patches but was not mapped at this scale.

Submontane Oak Dominated (code 5)

This class is dominated by Quercus alba, Quercus rubra, Quercus velutina, and Quercus falcata.  Other oaks present include Quercus prinus and Quercus
coccinea in the higher Piedmont with an increasing presence of Quercus stellata, Quercus palustris and Quercus michauxii in the Coastal Plain.  Other common
canopy associates include Carya spp. (ovata, cordiformis, glabra), Liriodendron tulipifera, Acer rubrum, and Liquidambar styraciflua.

Montane Oak Dominated (code 7)

This class is dominated by Quercus prinus, Quercus alba, Quercus rubra, and Quercus velutina.  On drier sites, Quercus coccinea and Q. prinus dominate with Q. alba and Q. rubra becoming more prevalent in concave landforms.  Common canopy associates include Carya spp. (ovata, cordiformis, glabra), Liriodendron
tulipifera, and Acer sacchrum in the Southeast and higher elevations.

Dry Oak Dominated (code 8)

This class is dominated by Q. prinus and Q. coccinea and is found in near pure stands on upper ridge mountain slopes with a Southerly aspect.

Mixed Central Hardwoods (code 9)
 
This class is extremely variable with no clear dominance at the stand level.  Species composition and dominance is often dictated by micro-conditions at the site.  The
canopy usually contains some Quercus spp. (alba, rubra, velutina, prinus, stellata, falcata) but is often joined by other species such as Liriodendron tulipifera,
Carya spp. (ovata, cordiformis, glabra), Acer saccharum, Acer rubrum, Robinia pseudoacacia, Liquidambar styraciflua, Nyssa sylvatica, Betula spp.
(alleghaniensis, lenta, nigra), Magnolia spp. (acuminata, fraseri), and Fagus grandifolia.
 

Riparian Forest (code 11)

This class is comprised of forest-water edge.  Common species are Platanus occidentalis, Betula nigra, Salix spp., Populus deltoides and Liriodendron tulipifera
depending on the geographic region of Virginia.  Other species are often present.

Tupelo/Red Maple Wet Forests (code 13)

This class is dominated by Nyssa sylvatica (aquatica), Acer rubrum, and Liquidambar styraciflua.  Other associates include Fraxinus spp.and Platanus occidentalis.

Red Cedar Woodlands (code 18)

Juniperus virginiana is found throughout Virginia where old fields and livestock pastures have been abandoned and allowed to regenerate.  These stands may be very dense or may contain other canopy trees in small numbers (commonly Pinus virginiana).

Mixed Herbaceous (code 30)

This type contains a spectral mix of non-forested, herbaceous classes.  It represents old fields, high grass-forb-sedge communities, and agricultural mix (crop rotation,
both row and field).

Sparse Herbaceous/Row Crop (code 31)

This class is mostly row crops of corn, soybean, tobacco, and cotton.  This class also contains areas with sparse herbaceous vegetation on bare ground common in
disturbed grass areas.

Field (code 36)

This class contains mostly field crops such as wheat and hay.  Some natural field regeneration and low pasture may also be present.

Pasture (code 38)

This class contains low grass/disturbed vegetation with complete or near-complete coverage.  Often animals are actively grazing these areas.

Open Water (code 40)

Open water of all kinds is represented.  This includes large streams, rivers, ponds, lakes, and off-shore areas of Chesapeake Bay and the Atlantic Ocean.

Non-vegetated (code 50)

This class represents non-vegetated areas such as beaches, quarries, and mines.  It also contains some light development.

High Intensity Disturbed/Urban (code 51, 53)

This class is comprised of high-density urbanization, roads, commercial areas, and impenetrable surfaces.  Mostly associated with cities and major roadways.

Low Intensity Disturbed/Residential (code 52)

This class results from the mix of residential structures and the managed lands surrounding them (often including trees, mowed areas, and gardens).

Recent Clearcut (code 56)

Areas which have been recently (typically within 5 years of image acquisition) disturbed through timber harvests.  These areas may contain some young forest or planted conifer (usually P. taeda), as well as skid trails and log deck areas.  This class is often found with the Submontane Yellow Pine class.

Wetland (code 60)

Areas that are, for some period of time during the year, affected by standing water.  This class includes open, shrub, and forested wetlands in salt, brackish, and
fresh water systems.

Herbaceous Wetland (code 61, 62)

This class depicts areas that contain wetland non-woody vegetation.  Typha spp., Phragmites spp., and Spartina spp. frequently dominate, depending on localized
conditions.
 

Coastal Shrub (code 63)

Areas with shrub cover on coastal areas.  Typically species include Myrica pensylvanica, Myrica cerifera, and Baccharis halimifolia.

Forested Wetland (code 64)

This class represents a variety of deciduous and coniferous forests that occur on wetlands as indicated by the National Wetlands Inventory (U.S. Fish and Wildlife
Service).  This type is found primarily in the Eastern part of Virginia.  Typical overstory species are likely to be Nyssa spp. (sylvatica, aquatica), Liquidambar
styraciflua, Acer rubrum, and Pinus taeda.  Other possible species include Populus deltoides, Liriodendron tulipifera, Betula nigra, and Platanus occidentalis.

Montane Dry Deciduous Forest Complex (code 111, 113)

This class identifies areas where specific types could not be identified.  This type is found on steep, South-facing slopes and convex areas.  Although this class is variable, it tends to be dominated by Montane Oak and Dry Montane Oak types with some Mixed Central Hardwood.  Acer saccharum-Fagus grandifolia-Betula
alleghaniensis is more abundant in higher elevations.  Some Liriodendron tulipifera may be found in the high Piedmont areas or on post-disturbance sites.

Montane Mesic Deciduous Forest Complex (code 112)

This class contains the same major forest members as does the Montane Dry Deciduous Forest Complex, except that the Montane Dry Oak type is greatly
reduced, with Mixed Central Hardwoods (Liriodendron tulipifera, Quercus velutina, Quercus rubra, Acer saccharum) replacing it.  This sites are found on the
more concave landforms on slighter slopes and more Northerly aspects.

Virginia Hardwood Complex (code 210 - 220, 231)

This class represents the upland deciduous forest types found in the Piedmont and Coastal Plain.  These types could not be differentiated accurately spectrally or through topography.  Mixed Central Hardwoods are frequently observed.  In an effort to further differentiate this class, subclasses based on a Relative Phenological Index
(RPI) and the East-wide Forest Inventory Analysis (U.S. Forest Service) data were created.  The composition of each phenological zone is given in Figure 1.

Figure 1.
 
 

The RPI classes can be broken down to the following sub-classes:

    1. Virginia Southern Coastal Plain Deciduous Forests
        - Mesic and hydric forest types comprise ~ 45% of the class with Quercus spp. and other hardwoods comprising ~ 40% of the canopy.
 
    2. Virginia Coastal Plain Deciduous Forests
        - Mesic and hydric forest types begin to wane in overall forest composition.  Liquidambar styraciflua-Liriodendron tulipifera comprises ~ 23% of the
        forest while Mixed Central Hardwood and Quercus dominated types are the major type at ~ 60%.  The Quercus spp. (alba, rubra)-Carya spp. type reaches
        its highest relative composition at 34% of all deciduous forests.

    3. & 4. Virginia Southeastern Piedmont Deciduous Forests
        - The hydric forest types such as Magnolia virginiana-Nyssa sylvatica-Acer rubrum begin to decline while Quercus spp.-Liriodendron tulipifera increases
        in composition.

    5. Virginia Piedmont Deciduous Forests
        - In these regions of Virginia, the abundance of Liquidambar styraciflua-Liriodendron tulipifera decreases while Quercus prinus begins to increase.
        Quercus spp. and other members of Mixed Central Hardwood begin to comprise the clear majority of the forests.

    6.- 10. Virginia High Piedmont-Mountain Deciduous Forests
        - Throughout the higher elevations of Virginia Quercus spp. (alba, rubra, prinus) clearly dominate the deciduous forest.  Q. prinus continues to increase in class
        composition to the higher elevations.  Riparian species such as Platanus occidentalis are still found along major perennial streams, and Liriodendron
        tulipifera is increasingly restricted to concave landforms as RPI class increases.  The diversity of overstory hardwoods also increases (note the increase in
        percent composition of Mixed Central Hardwoods) to include Acer saccharum and Fagus grandifolia.
 
 
Piedmont/Coastal Plain Forest Complex (code 100 - 106)

This class represents the upland deciduous and coniferous forest types found in the Piedmont and Coastal Plain.  These types could not be differentiated accurately
spectrally or through topography.  In an effort to further differentiate this class, subclasses based on a Relative Phenological Index (RPI) and the East-wide Forest
Inventory Analysis (U.S. Forest Service) data were created.  The composition of each phenological zone is given in Figure 2.

Figure 2.

 

After RPI class 6, coniferous forest occupies less than 10% of the forest types.  The conifers of RPI class 1 are dominated by Pinus taeda with Pinus virginiana
increasing as a component as RPI class value increases.  Figure 3. shows the forest types for these classes.

Figure 3.
Piedmont/Coastal Plain Forests

 
 

These forests are often have predictable distributions if factors such as hydrology, soils, and topography are considered.  In general, the classes can be broken down to
the following sub-classes:

    1. Virginia Southern Coastal Plain Forests
        - Pinus taeda and P. taeda-Hardwood make up ~ 45% of the class with Quercus spp.  ~ 20% and other hardwoods comprising ~ 35% of the canopy.
 
    2. Virginia Coastal Plain Forests
        - Pinus taeda types still comprise over 40% of the overall forest composition.  Deciduous forests are dominated by Mixed Central Hardwood and Quercus  types
        at  ~ 30%.  The remainder of the forests are dominated by more hydrophilic species (Liquidambar styraciflua, Nyssa spp., etc.).

    3. & 4. Virginia Southeastern Piedmont Forests
        - Coniferous and Mixed forests occupy nearly 50% of the forests.  Pinus taeda is still frequent, but is joined by Pinus virginiana.  The hydric forest types
        such as Magnolia virginiana-Nyssa sylvatica-Acer rubrum begin to decline while Quercus spp.-Liriodendron tulipifera increases in composition.

    5. Virginia Piedmont Forests
        - In these regions of Virginia, the abundance of Pinus taeda decreases while Quercus spp. and other members of Mixed Central Hardwood begin to
        comprise the clear majority of the forests.  Pinus virginiana and Pinus taeda still comprise about 25% of the forests.

    6.- 10. Virginia High Piedmont-Mountain Forests
        - Throughout the higher elevations of Virginia, Quercus spp. (alba, rubra, prinus) clearly dominate the forest.  Q. prinus continues to increase in class
        composition in the higher elevations.  Riparian species such as Platanus occidentalis are still found along major perennial streams, and Liriodendron
        tulipifera is increasingly restricted to concave landforms as RPI class increases.  The diversity of overstory hardwoods also increases (note the increase in
        percent composition of Mixed Central Hardwoods) to include Acer saccharum and Fagus grandifolia.
 

Mixed-Pixel/Unknown (code 99)

This class is a conglomerate of all pixels which remained "unclassified".  Field analysis shows that these types often coincide with transition areas between types (e.g., pasture/forest edge) or an odd mix of major types (e.g., a manicured lawn under a partial forest canopy).
 

For additonal information contact:

Scott Klopfer
GIS/Remote Sensing Project Coordinator
Fish and Wildlife Information Exchange
Virginia Tech
Mail stop 0534
Blacksburg, VA 24061

phone: (540) 231-7348

sklopfer@vt.edu