MARITIME SHRUB (NORTHERN SUBTYPE)

Comments: This subtype is not as strongly differentiated as most subtypes. The characteristic coastal fringe flora are only marginal in their tolerance of Sand Barren habitats, and are a less prominent part of the community than they are in the Coastal Fringe subtypes of Xeric Sandhill Scrub and Pine/Scrub Oak Sandhill. However, the climatic factors that support coastal fringe flora in all these community types are likely to have effects on other organisms in the community (animals, microbes) and on ecosystem processes, even in the extreme environment of Sand Barrens.

XERIC SANDHILL SCRUB (TYPIC SUBTYPE) G3?

Xeric Sandhill Scrub (Turkey Oak Variant); Xeric Sandhill Scrub (Coastal Plain Variant); Pinus palustris / Quercus laevis / Gaylussacia dumosa var. dumosa / Aristida stricta Woodland (3586).

Concept: The Xeric Sandhill Scrub type covers the widespread longleaf pine communities of dry, coarse, infertile sands, which have low diversity scrub oak layer strongly dominated by Quercus laevis, but which have fairly high cover of Aristida stricta and do not meet the criteria for Sand Barrens. The Typic Subtype covers most examples of the Sandhills, inner and middle Coastal Plain, where plants characteristic of the coastal fringe are absent.
Distinguishing Features: Xeric Sandhill Scrub is distinguished from Sand Barren by higher plant cover in the herb layer, especially of Aristida stricta. Lichens and specialized psammophytes such as Stipulicida setacea and Arenaria caroliniana, may be present but are minor in abundance in comparison with Aristida stricta. Xeric Sandhill Scrub is distinguished from all other community types by the presence of a scrub oak layer strongly dominated by Quercus laevis. The Typic Subtype is distinguished from the Coastal Fringe Subtype by the absence of characteristic coastal fringe flora, such as Cladina evansii, Rhynchospora megalocarpa, Ilex vomitoria, and Quercus geminata.

XERIC SANDHILL SCRUB (COASTAL FRINGE SUBTYPE) G2?

Synonyms: Pinus palustris / Quercus laevis - Quercus geminata / Vaccinium tenellum / Aristida stricta Woodland (3589).

Concept: The Xeric Sandhill Scrub type covers the widespread longleaf pine communities of dry, coarse, infertile sands, which have low diversity scrub oak layer strongly dominated by Quercus laevis, but which have fairly high cover of Aristida stricta and do not meet the criteria for Sand Barrens. The Coastal Fringe Subtype covers examples near the coast (at least in North Carolina) which have characteristic coastal fringe flora.
Distinguishing Features: Xeric Sandhill Scrub is distinguished from Sand Barren by higher plant cover in the herb layer, especially of Aristida stricta. Lichens and specialized psammophytes such as Stipulicida setacea and Arenaria caroliniana, may be present but are minor in abundance in comparison with Aristida stricta. Xeric Sandhill Scrub is distinguished from all other natural community types by the presence of a scrub oak layer strongly dominated by Quercus laevis. The Typic Subtype is distinguished from the Coastal Fringe Subtype by the presence of characteristic coastal fringe flora, such as Cladina evansii, Rhynchospora megalocarpa, Ilex vomitoria, and Quercus geminata.


PINE/SCRUB OAK SANDHILL (MIXED OAK SUBTYPE) G3?

Synonyms: Pinus palustris / Quercus laevis - (Quercus incana, margarettiae) / Gaylussacia dumosa var. dumosa / Aristida stricta Woodland (3591).

Concept: The Pine/Scrub Oak Sandhill type covers dry longleaf pine communities that are less xeric and infertile than the Xeric Sandhill Scrub type, and are characterized by a scrub oak layer containing a mixture of oak species. The Mixed Oak Subtype covers examples on fine sands or slightly silty soils without clay, and which therefore have a mixture of scrub oaks that does not include Quercus marilandica. It is the subtype that is closest to Xeric Sandhill Scrub in character.
Distinguishing Features: The Pine/Scrub Oak Sandhill type is distinguished from Xeric Sandhill Scrub and Sand Barren by the substantial presence of scrub oaks other than Quercus laevis; Quercus marilandica is present, or Q. incana, Q. margarettiae, Q. hemisphaerica, or other oaks are present in significant numbers, though Quercus laevis may still be the most abundant oak. Pine/Scrub Oak Sandhill is distinguished from Mesic Pine Flatwoods and wetter longleaf pine communities by the presence of a substantial understory of scrub oaks, or a substantial shrub layer of scrub oak sprouts in recently burned examples. Fire-suppressed Mesic Pine Flatwoods may contain forest oaks such as Quercus stellata, Q. falcata, Q, velutina, and Q. nigra. Pine/Scrub Oak Sandhill is distinguished from Piedmont Longleaf Pine Forest by the absence of characteristic Piedmont upland forest species such as Oxydendrum arboreum, Quercus montana, and Quercus coccinea, and in the most natural examples, by the absence of a substantial component of Pinus taeda or Pinus echinata. Substrate should also distinguish these two types.
The Mixed Oak Subtype is characterized by abundant Quercus laevis, Q. incana, Q. margarettiae, or Q. hemisphaerica. It is distinguished from the Blackjack and Clay/Rock Hilltop Subtypes by the absence of Quercus marilandica. It is distinguished from the Mesic Transition Subtype by a lower diversity herb layer (though still fairly high diversity) that lacks mesic species. It is distinguished from the Northern Subtype by occurring within the range of Aristida stricta, and having it, at least historically, present. It is distinguished from the Coastal Fringe Subtype by lacking plants that, in North Carolina at least, are largely confined to near the coast. These include Quercus geminata, Quercus virginiana, Osmanthus americana, Ilex vomitoria, Rhynchospora megalocarpa, and Cladina evansii. Quercus hemisphaerica is more often abundant in the Coastal Fringe Subtype, but may also be abundant in the Mixed Oak Subtype.


PINE/SCRUB OAK SANDHILL (BLACKJACK SUBTYPE) G2G3

Synonyms: Pinus palustris / Quercus marilandica / Gaylussacia dumosa var. dumosa / Aristida stricta Woodland (3595).

Concept: The Pine/Scrub Oak Sandhill type covers dry longleaf pine communities that are less xeric and infertile than the Xeric Sandhill Scrub type, and are characterized by a scrub oak layer containing a mixture of oak species. The Blackjack Subtype covers the common examples, primarily of the Sandhills Region, where clay is present in the soil below a sandy surface, and Quercus marilandica is a component.
Distinguishing Features: The Pine/Scrub Oak Sandhill type is distinguished from Xeric Sandhill Scrub and Sand Barren by the substantial presence of scrub oaks other than Quercus laevis; Quercus marilandica is present, or Q. incana, Q. margarettiae, or other oaks are present in significant numbers, though Quercus laevis may still be the most abundant oak. Pine/Scrub Oak Sandhill is distinguished from Mesic Pine Flatwoods and wetter longleaf pine communities by the presence of a substantial understory of scrub oaks, or a substantial shrub layer of scrub oak sprouts in recently burned examples. Fire-suppressed Mesic Pine Flatwoods may contain forest oaks such as Quercus stellata, Q. falcata, Q, velutina, and Q. nigra. Pine/Scrub Oak Sandhill is distinguished from Piedmont Longleaf Pine Forest by the absence of characteristic Piedmont upland forest species such as Oxydendrum arboreum, Quercus montana, and Quercus coccinea, and in the most natural examples, by the absence of a substantial component of Pinus taeda or Pinus echinata. Substrate should also distinguish these two types, and all but a couple Piedmont Longleaf Pine Forests lack Aristida stricta.
The Blackjack Subtype is distinguished from the Mixed Oak Subtype by the presence of appreciable amounts of Quercus marilandica. It is distinguished from the Clay/Rock Hilltop Subtype by the presence of Quercus laevis, the absence of Vaccinium crassifolium and other wetland species, and the presence of sand at the soil surface. It is distinguished from the Mesic Transition Subtype by the absence of characteristic more mesic herbs and shrubs, though the herb layer may be fairly diverse. It is distinguished from the Northern Subtype by the presence, at least historically, of Aristida stricta.


PINE/SCRUB OAK SANDHILL (MESIC TRANSITION SUBTYPE) G2G3

Synonyms: Pine/Scrub Oak Sandhill (Loamy Soil Variant); "pea swales"; Pinus palustris / Quercus incana / Aristida stricta - Sorghastrum nutans - Anthaenantia villosa Woodland (3578).

Concept: The Pine/Scrub Oak Sandhill type covers dry longleaf pine communities that are less xeric and infertile than the Xeric Sandhill Scrub type, and are characterized by a scrub oak layer containing a mixture of oak species. The Mesic Transition Subtype covers the generally very localized examples with loamy soil, greater fertility, or possibly closer proximity to the water table, which support a very diverse flora that includes mesic herb and shrub species. They share many plants with Mesic Pine Flatwoods, but have a significant scrub oak component.
Distinguishing Features: See above for distinguishing the Pine/Scrub Oak Sandhill type. This subtype is often transitional to Mesic Pine Flatwoods, and should be distinguished by the presence of scrub oaks in significant numbers (these may be reduced in density and present as shrub-size sprouts if the site has been frequently burned). Communities in which oaks have been artificially eradicated may be difficult to distinguish, but will have a flora that will lack the small component of wetland species usually found in Mesic Pine Flatwoods.
The Mesic Transition Subtype is distinguished from all other subtypes by the substantial presence of characteristic mesic grasses, legumes, and composites, such as Anthaenantia villosa, Sorghastrum nutans, Andropogon gerardii, Paspalum bifidum, Tridens carolinianum, Lespedeza capitata, Lespedeza hirta, and Helianthus divaricatus. [need more] The scrub oaks are often noticeably less dense in this subtype than in the Blackjack Subtype under the same management regime.


PINE/SCRUB OAK SANDHILL (CLAY/ROCK HILLTOP) G2?

Synonyms: Pinus palustris / Quercus marilandica / Vaccinium crassifolium / Aristida stricta Woodland (3599).

Concept: The Pine/Scrub Oak Sandhill type covers dry longleaf pine communities that are less xeric and infertile than the Xeric Sandhill Scrub type, and are characterized by a scrub oak layer containing a mixture of oak species. The Clay/Rock Hilltop covers the rare (in North Carolina) examples where clay or consolidated rock is exposed at the soil surface, which generally support a sparser scrub oak layer that lacks Quercus laevis and which haveVaccinium crassifolium and Pyxidanthera barbulata as significant components.
Distinguishing Features: See above for distinguishing the Pine/Scrub Oak Sandhill Type. The Clay/Rock subtype is distinguished from all other subtypes by occurrence on sandstone or hard clay surfaces rather than sand, by the absence of Quercus laevis and the presence of Vaccinium crassifolium or Pyxidanthera barbulata in a hilltop location (a location that would otherwise be well drained).


PINE/SCRUB OAK SANDHILL (COASTAL FRINGE SUBTYPE) G2

Synonyms: Coastal Fringe Sandhill; Pinus palustris - Pinus taeda / Quercus geminata - Quercus hemisphaerica - Osmanthus americanus var. americanus / Aristida stricta Woodland (3577).

Concept: The Pine/Scrub Oak Sandhill type covers dry longleaf pine communities that are less xeric and infertile than the Xeric Sandhill Scrub type, and are characterized by a scrub oak layer containing a mixture of oak species. The Coastal Fringe Subtype covers communities near the coast (in North Carolina) which contain characteristic coastal fringe plants, including evergreen scrub oaks. It was formerly treated as a separate community type, but falls within the moisture range and broader concept of Pine/Scrub Oak Sandhill.
Distinguishing Features: See above for distinguishing Pine/Scrub Oak Sandhills. The Coastal Fringe Subtype is distinguished by the presence of plant species that, at least in North Carolina, are confined to near the coast. These include Quercus geminata, Osmanthus americana, Ilex vomitoria, Rhynchospora megalocarpa, and Cladina evansii. Quercus hemisphaerica is often abundant in the Coastal Fringe Subtype, but examples that have Quercus hemisphaerica and none of the other indicators are classified as the Mixed Oak Subtype.
Among the Coastal Fringe subtypes of the different sandhills, these communities are distinguished by being more mesic and having greater overall plant cover and diversity than the Xeric Sandhill Scrub or Sand Barren. Quercus geminata often is more abundant than Quercus laevis, and Q. hemisphaerica, Q. incana, Q. margarettiae, and Q. virginana are generally present. Bare sand is limited in extent and the most specialized psammophytes are not as abundant.

PINE/SCRUB OAK SANDHILL (NORTHERN SUBTYPE) G1

Synonyms: Pinus palustris / Quercus laevis - Quercus incana / Gaylussacia dumosa var. dumosa - Gaylussacia (baccata, frondosa) Woodland (3592).

Concept: The Pine/Scrub Oak Sandhill type covers dry longleaf pine communities that are less xeric and infertile than the Xeric Sandhill Scrub type, and are characterized by a scrub oak layer containing a mixture of oak species. The Northern Subtype covers the few examples that are north of the natural range of Aristida stricta. This is conceptually a broader range of moisture and soil conditions than the other subtypes, but remaining examples are too few and too degraded to refine the category further.
Distinguishing Features: See above for distinguishing Pine/Scrub Oak Sandhill. The Northern Subtype is distinguished from all other subtypes by its geographic location north of the natural range of Aristida stricta, roughly at Pamlico sound and the Neuse River. The only other dry longleaf pine community that naturally lacks Aristida stricta is the Piedmont Longleaf Pine Forest, of which none are known this far north and which differ in their composition.

MESIC PINE SAVANNA (COASTAL PLAIN SUBTYPE) G2G3

Synonyms: Mesic Pine Flatwoods (Coastal Plain Variant); Pinus palustris / Amorpha herbacea var. herbacea / Aristida stricta - Sorghastrum nutans Woodland (3569).

Concept: The Mesic Pine Savanna type covers longleaf pine communities of environments intermediate between sandhills and wet savanna. The Coastal Plain Subtype covers the typical examples of the middle and lower Coastal Plain, which differ floristically and in landscape relations from the other subtypes.
Distinguishing Features: The Mesic Pine Savanna type is distinguished from Pine/Scrub Oak Sandhill and other sandhill types by the substantial absence of scrub oaks or their presence combined with that of wetland species. Forest oaks such as Quercus nigra, Q. falcata, or Q. stellata may be present in fire-suppressed examples. Mesic Pine Savannas are distinguished from the wet pine savannas by having a substantial component of mesophytic plants and only small amounts wetland plants, or having wetland plants in combination with scrub oaks. Mesic Pine Savannas contain a substantial and usually diverse component of legume species, which are largely absent in wet pine savannas. Characteristic plants that occur in wet savannas and not in mesic savannas include Sporobolus pinetorum, Ctenium aromaticum, Muhlenbergia expansa, most Rhynchospora species, Andropogon glomeratus, Eriocaulon spp., Bigelowia nudata, Zigadenus spp., and all insectivorous plants.
The Coastal Plain Subtype from the other subtypes by floristic differences. It is distinguished from the Lumbee Subtype and the Little River Subtype by the absence of scrub oaks and any appreciable amount of wetland plants. The distinction with the Sandhills Subtype is based on floristic differences that are less clear cut, but the two can readily be distinguished by geographic location, as no examples are known in North Carolina outside of their respective geographic areas. Plants that occur in the Coastal Plain Subtype and seldom or never in the Sandhills Subtype include Amorpha herbacea var. herbacea, Carphephorus odoratissimus, Tephrosia hispidula, Desmodium tenuifolium, Liatris graminifolia, and Coreopsis oniscicarpa. Plants that occur in the Sandhills Subtype and seldom or never in the Coastal Plain include Anthaenantia villosa, Paspalum bifidum, Liatris cokeri, and Tridens carolinianus. The Coastal Plain Subtype usually occurs on flat terrain distant from drainages, in large to small patches, or often in a fine mosaic with Wet Loamy Pine Savanna communities.
Comments: The distinction between the Coastal Plain and Sandhills subtypes needs further examination, and may not be warranted. These subtypes share virtually all of their dominant species.

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