Moist Sandy Wet-Mesic Flatwoods

Description

Mesic Flatwoods are pine woodlands with well-developed and pyrogenic ground cover vegetation, consisting of many species of grasses, forbs, sedges and shrubs. Notable ground cover shrub species include: saw palmetto (Serenoa repens), gallberry (Ilex glabra), coastalplain staggerbush (Lyonia fruticosa), and fetterbush (Lyonia lucida). Oaks typical of scrubs, scrubby flatwoods and sandhills are absent. Runner oaks (Q. minima, Q. pumila) are the only common oaks generally present in mesic flatwoods, and they are confined to the ground cover. Wiregrass is the dominant bunch grass, although other common grasses include: bluestems (Andropogon spp.), lopsided Indiangrass (Sorghastrum secundum), panicgrasses (Dichanthelium spp.), and other three-awned grasses (i.e. Aristida spiciformis).

Wet Flatwoods are structurally and aesthetically similar to mesic flatwoods, although they are compositionally dissimilar. Similar pine species form the woodland canopy. Midstory vegetation is sparse in frequently burned areas. If present, it may contain scattered hardwoods (but generally, not oaks), such as sweetbay (Magnolia virginiana), swamp bay (Persea palustris), loblolly bay (Gordonia lasianthus), dahoon (Ilex cassine), large gallberry (Ilex coriacea), fetterbush (Lyonia lucida), red chokeberry (Photinia pyrifolia), saw palmetto (Serenoa repens) and gallberry (I. glabra). Herbs include wiregrass (Aristida stricta) and many other species of hydrophytic grasses and forbs. Particularly notable is the diversity of sedge species, many belonging to the genus Rhynchospora.

Submodel

Description

State 2 describes closed canopy forests following long term fire suppression or exclusion. Mesic hammocks replace mesic flatwoods with fire exclusion, as live oaks dominate closed canopies and shade out most understory herbaceous vegetation. Wet flatwoods are similarly replaced by closed canopy hammock forests, although the tree composition differs (includes hydrophytic species).

In closed canopy forests, the floor is covered with oak leaf litter which holds considerable moisture and engenders mesic conditions, further depressing native herbaceous growth, pine germination, and frequent fires (FNAI, 2010).

Submodel

Description

This state describes a restored pine woodland with similar structure and ecological function to that of State 1 (mesic or wet flatwoods). Notably, this state describes conditions where native propagules have been extirpated following long term fire suppression and/or extensive soil disturbance associated with commodity land uses, followed by artificial establishment of native clonal oaks and other scrub shrub species. Many native species are absent, and weedy or residual non-native species may persist in this restored scrub community. Herbaceous species are absent, weedy or non-native, depending on pre-restoration conditions and geography.

Restoration of native oaks provides fuels for infrequent fires necessary for ecological functioning and dynamics. Once established, clonal oaks may provide habitat suitable for establishment of other native plant populations, either from artificial seeding or natural recruitment.

The full complement of native species remains incomplete in State 3. Perennial grasses and forbs with seed dispersal mechanisms not conducive to colonization of distant and disturbed sites are notably absent (i.e. big seeded species which rely on animal and gravity dispersal, and long lived clonal species). However, over time, native plants may recolonize, particularly wind-dispersed native herbaceous species.

Submodel

Description

State 4 describes a condition where one or more noxious non-native plant species has invaded and dominated the site. By far the most common invasive plant species is cogongrass (Imperata cylindrica). This highly clonal grass spreads rapidly by underground rhizomes and windblown seeds, forming dense circular patches which can become very large (on the order of 100’s of acres). Cogongrass is a prolific seed producer, and readily invades following soil disturbances. Once clones are established, rapid cogongrass growth will extirpate native ground cover plant populations. In addition, cogongrass may be allelopathic in some situations. In general, cogongrass may colonize conditions with plenty of sun exposure and open ground. Soil disturbance is conducive to cogongrass colonization.

Submodel

Description

This State describes commodity land uses of this site.

Submodel