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bottomland forest

Sites

Floodplain ridges and terraces other than active levees adjacent to the river channel.

Soils

Various alluvial soils, typically Altavista, Chewacla, and Congaree.

Hydrology

Palustrine, intermittently flooded.

Vegetation

Canopy

Canopy dominated by various bottomland trees such as Liquidambar styraciflua (Sweet Gum), Fraxinus pennsylvanica (Green Ash), Quercus michauxii (Basket Oak), Q. pagoda (Cherrybark Oak), Liriodendron tulipifera (Tulip-tree), Ulmus americana (American Elm), Celtis laevigata (Southern Hackberry), Carya ovata (Common Shagbark Hickory), and C. cordiformis (Bitternut Hickory).

Understory

Understory trees include Acer rubrum (Eastern Red Maple), A. floridanum (Southern Sugar Maple), Ilex decidua (Possum-haw), I. opaca (American Holly), Carpinus caroliniana (American Hornbeam), Cornus florida (Flowering Dogwood), and Asimina triloba (Common Pawpaw). Shrubs include species such as Euonymus americanus (Strawberry-bush), Viburnum prunifolium (Black Haw), and Aesculus sylvatica (Painted Buckeye). Arundinaria gigantea (Giant Cane) may form dense thickets. Vines are frequently prominent, including Toxicodendron radicans (Eastern Poison Ivy), Campsis radicans (Trumpet-creeper), Parthenocissus quinquefolia (Virginia-creeper), Smilax spp. (Greenbriar), Bignonia capreolata (Cross-vine), Vitis spp. (Wild Grape), and Menispermum canadense (Moonseed).

Herb Layer

Herbs include Boehmeria cylindrica (False Nettle), Viola spp. (Violet), Arisaema triphyllum (Common Jack-in-the-pulpit), Carex spp. (Sedge), Elymus virginicus (Common Eastern Wild-rye), Persicaria virginiana (Jumpseed), Chasmanthium latifolium (River Oats), C. laxum (Slender Spikegrass), Polystichum acrostichoides (Christmas Fern), Solidago caesia (Axillary Goldenrod), Cryptotaenia canadensis (Honewort), Packera aurea (Golden Ragwort), and Eurybia divaricata (Common White Heart-leaved Aster). Some places are heavily invaded by Lonicera japonica (Japanese Honeysuckle) and Microstegium vimineum (Japanese Stilt-grass), and the native herbs are suppressed.

Dynamics

These communities are flooded, at least occasionally, and are seldom disturbed by flowing water. They receive significant input of nutrients through sediment deposition. Bottomland Forests are believed to form a stable climax forest, having an uneven-aged canopy with primarily gap phase regeneration, although the possibility of unusually deep and prolonged flooding may make widespread mortality more likely than in uplands. Areasthat have been cleared or heavily logged in the past may have abundant or dominant disturbance species such as Pinus taeda (Loblolly Pine), Acer rubrum, Liquidambar styraciflua or Platanus occidentalis (Sycamore). It appears that any bottomland forest strongly dominated by Liriodendron tulipifera is probably a successional forest developing after cultivation.

Associations

Grades into Levee Forest or Swamp Forest within the floodplain. May grade to various mesic, dry-mesic, or dry forest communities.

Comments

Bottomland Forest is defined as the portion of the flooding gradient where most oaks occur. Because of the relatively steep gradients and narrow floodplains in the Piedmont, rivers with fluvial landforms large enough to allow recognition of levee, swamp, and bottomland are less common than in the Coastal Plain. Even large river floodplains may contain alternating stretches of narrow and broad floodplain. The fertility and infrequent flooding in these sites have made them excellent farm lands. Very few bottomlands of any significant size remain. While many bottomlands exist as successional forests grown up in abandoned fields, intact Bottomland Forests are among the rarest of communities in North Carolina.