Classification of Vegetation Communities of Maryland: First Iteration
A Subset of the International Classification of Ecological
Concept: This alliance includes tidal, mesohaline to oligohaline marshes dominated or codominated by Schoenoplectus americanus (= Scirpus olneyi). Other associated species can include Spartina patens, Spartina alterniflora, Spartina cynosuroides, Phragmites australis, Juncus roemerianus, Typha spp., and Typha domingensis. The general aspect and species composition of this vegetation are variable, not only among occurrences, but also over the course of the growing season. Dominance patterns are not well understood but are likely related to gradients in salinity and hydrology. This alliance is known from the Gulf Coast of Texas, the Chenier Plain of Louisiana, and the mid-Atlantic coast of Maryland and Delaware; it may also occur along the Gulf Coast of Mississippi and Alabama and possibly along the lower Atlantic coast of the United States.
Comments: This alliance was created to cover coastal marsh vegetation dominated by Schoenoplectus americanus (JT 4-01).
Range: This alliance is currently only known from the Gulf Coast of Texas, the Chenier Plain of Louisiana, and the mid-Atlantic coast of Maryland and Delaware, but it may range throughout the Gulf Coast and lower and mid-Atlantic coast of the U.S.
States/Provinces: AL? DE GA? LA MD MS? NC? SC? TX VA
TNC Ecoregions: 31:C, 56:?, 57:C, 58:C, 62:C
USFS Ecoregions: 231Fb:CCC, 232Ac:CCC, 232Br:CCC, 232Bx:CCC, 232Bz:CCC, 232Ch:CCC, 232Eb:CCC, 255Dc:CCC
Federal Lands: USFWS (Anahuac, Brazoria, McFaddin, San Bernard)
References: Visser and Sasser 1998, Visser et al. 1998
Authors: J. TEAGUE, Southeast Identifier: A.2007
SCHOENOPLECTUS AMERICANUS - SPARTINA PATENS HERBACEOUS VEGETATION
Chairmaker's Bulrush - Saltmeadow Cordgrass Herbaceous Vegetation
Ecological Group (SCS;MCS): Atlantic and Gulf Coast Salt and Brackish Tidal Marshes (202-30; n/a)
Concept: This brackish marsh occurs in wet depressions at the upper reaches of irregularly flooded tidal marshes of the mid-Atlantic coast. It occurs at the ecotone between low and high salt marsh zones. It is irregularly flooded, occurring just above the zone of regular tidal flooding, but is more frequently flooded than Spartina patens-dominated high marsh. This community is dominated by colonies of Schoenoplectus americanus, which often accounts for 40-75% of the total vegetation cover or codominant with Spartina patens at some sites. Associated species can include Pluchea odorata, Juncus roemerianus, Spartina alterniflora, Spartina cynosuroides, Distichlis spicata, and Limonium carolinianum plus Typha spp. and Phragmites australis. This community often grades into Spartina patens- or Juncus roemerianus-dominated high marsh landward or Spartina alterniflora- or Spartina cynosuroides-dominated low marsh seaward. This association is best developed where the elevation gradient across the marsh is more gradual, allowing for greater diversity of physical conditions of duration and frequency of flooding.
Comments: The relationship between this alliance and the similar Spartina patens - (Distichlis spicata) Tidal Herbaceous Alliance (A.1481) is not well understood. Dominance patterns are likely related to gradients in salinity and hydrology. Schoenoplectus americanus may dominate in areas with higher average water levels, lower salinities, and lower frequency of flooding than areas typically dominated by Spartina patens.
Range: This association is currently described from mid-Atlantic states of Delaware, Maryland and Virginia. It possibly extends south to Georgia.
States/Provinces: DE:S?, GA?, MD:S4, NC?, SC?, VA:S?
TNC Ecoregions: 56:?, 57:C, 58:C, 62:C
USFS Ecoregions: 232Ac:CCC, 232Br:CCC, 232Bx:CCC, 232Bz:CCC, 232Ch:CCC
References: Bowman 2000, Fleming 2001, Fleming et al. 2001, Harrison 2001
Authors: S.L. Neid, ECS Confidence: 2 Identifier: CEGL006612
- Maryland Vegetation Classification Subset Report V.A. Perennial graminoid vegetation
|Return to Table of Contents|
This Page Up-dated on April 27, 2010