Sumter National Forest Final Report - NatureServe

large variations in stream flow (Mulholland and Lenat 1992). Podostemum is one of the few vascular plants present in Piedmontstreams and rivers.Vegetation: This vegetation is almost always a monospecific community dominated by Podostemum ceratophyllum with no othervascular plants present; some Rhodophyta (red algae) may be present.Dynamics: Podostemum appears to require relatively stable streamflow to accumulate significant biomass; at high nutrient levelsfilamentous green algae may outcompete it (Mulholland and Lenat 1992). Dense beds of this vegetation may serve as importantsubstratum for a variety of invertebrates and other aquatic species (Nelson and Scott 1962). At least one rare species of snail of thePiedmont drainages, Somatogyrus virginicus, appears to be very closely tied to the occurrence of good beds of Podostemum (B.Adams pers. comm.). Although it is not clear whether the snail is actually dependent on Podostemum, it could be that Podostemum isjust a good habitat indicator.Similar Associations:Related Concepts:• Mountain river (Wharton 1978) ?• Open Water/Aquatic Bed Veg., Mountain Stream (Ambrose 1990a) B• River-weed shallow shore (CAP pers. comm. 1998) ?• Rocky Bar and Shore (Riverweed Subtype) (Schafale 1998b) ?Classification Comments: Podostemum could easily be the poster child of Piedmont rivers (B. Adams pers. comm.); it is unlikelythat many aquatic plant species in the Piedmont have been hit harder. It is very sensitive to sedimentation and, accordingly, hasdeclined greatly throughout its range and has been lost from nearly all areas it once occupied in some drainages such as the UpperNeuse Basin of North Carolina (Adams pers. comm.). This vegetation has been documented from the Sepulga River in the East GulfCoastal Plain of Alabama, the upper Duck River at Manchester (Old Stone Fort State Park) in the Interior Low Plateau of Tennessee,the Middle Oconee River, Georgia (Nelson and Scott 1962), the Eno River and formerly many sites in the Upper Neuse River Basinin the Piedmont of North Carolina (B. Adams pers. comm.), the Savannah River, and the Mechums and South Anna rivers in Virginia(Mulholland and Lenat 1992). It is apparently rare in Arkansas, found primarily in the Arkansas River and apparently in the OuachitaRiver (Smith 1988b). This type may also occur in the base-rich waters of the Shenandoah River and its two forks, the James River andportions of the Roanoke River (Fleming et al. 2001). In Georgia, this type appears to be restricted to the Piedmont and is apparentlyabsent from the northwestern part of the state (Jones and Coile 1988).CONSERVATION RANKING & RARE SPECIESGRank: G3G5 (2002-8-19): Although this species appears to have a fairly extensive range across the eastern United States, it isunclear whether all geographic areas supporting the species actually support stands of this association. Secondly, Podostemum may bein trouble across large parts of this range. It is very sensitive to sedimentation and watershed erosion (Mulholland and Lenat 1992).These factors may have contributed to declines of this type in the Piedmont, where it has been lost from many areas historicallyoccupied in drainages such as the Upper Neuse (B. Adams pers. comm.). It also appears to be sensitive to nutrient enrichment whichmay cause this species to be outcompeted by algae.High-ranked species: Helisoma eucosmium (G1Q), Somatogyrus virginicus (G1G2)ELEMENT DISTRIBUTIONRange: This community is wide-ranging, occurring in rivers throughout the eastern and southeastern United States.Subnations: AL, AR, CT, DE, GA, KY, LA?, MA, MD, ME, NC, NH, NJ, NY, OK, PA, RI, SC, TN, VA, VTTNC Ecoregions: 38:C, 39:C, 43:C, 44:C, 50:C, 51:C, 52:C, 53:C, 59:C, 60:C, 61:CUSFS Ecoregions: 212Fa:CCP, 212Fc:CCC, 212Fd:CCP, 212Ga:CCP, 212Gb:CCP, 221Ae:CCC, 221Af:CCC, 221Ag:CCC,221Ah:CCP, 221Ai:CCC, 221Al:CCP, 221Am:CCC, 221Bd:CCC, 221Da:CCC, 221Db:CCP, 221Dc:CCP, 221Ha:CCC,221Hb:CCC, 221Hc:CCC, 221He:CCC, 222Eb:CCC, 222En:CCP, 222Eo:CCP, 231Af:CCC, 232Bj:CCC, M212Bb:CCC,M212Bc:CCP, M212Bd:CCP, M221Aa:CC?, M221Ab:CC?, M221Ac:CCC, M221Ad:CC?, M221Bb:C??, M221Bd:C??,M221Be:C??, M221Bf:C??, M221Da:CC?, M221Dc:CCC, M221Dd:CCC, M222Aa:CCC, M231Aa:CCC, M231Ab:CCC,M231Ac:CCC, M231Ad:CCCFederal Lands: USFS (Daniel Boone, Oconee?, Ouachita, Ozark, Sumter, Uwharrie)ELEMENT SOURCESReferences: Adams pers. comm., Ambrose 1990a, Breden et al. 2001, CAP pers. comm. 1998, Campbell et al. 1990, Fleming et al.2001, Hoagland 2000, Jones and Coile 1988, Mulholland and Lenat 1992, Nelson 1986, Nelson and Scott 1962, Peet et al. unpubl.data 2002, Schafale 1998b, Schafale and Weakley 1990, Smith 1988b, Southeastern Ecology Working Group n.d., Thomas and Allen1993, Wharton 1978ROCKY-SHOAL SPIDERLILY - COMMON WATER-WILLOW HERBACEOUS VEGETATIONELEMENT IDENTIFIERSNVC association: Hymenocallis coronaria - Justicia americana Herbaceous VegetationDatabase Code: CEGL004285Vegetation of Sumter National Forest April 30 2004Copyright © 2004 NatureServe92