Class: Spartina patens- Distichlis spicata Tidal Herbaceous Alliance (Spartina High Salt Marsh) TNC Alliance Code: V. A. 5 N. n. 11.  6006 CMI Code: 6006 Island Locator:  Fire Island and Floyd Estate occurs generally along bay side of island and along other protected shores Cross Section:

TNC Alliance Description:  This high salt marsh vegetation occurs above low salt marsh on the bay side of barrier beaches.  The substrate is characterized by shallow peat over sand. High salt marsh vegetation occurs between low salt marsh and maritime forest or maritime shrubland.  Distichlis spicata and Spartina patens are co-dominant and often form dense cover. Salicornia spp. can form dense patches and Spartina alterniflora often occurs as scattered clumps.  Limonium carolinianum and Solidago sempervirens can occur sporadically
 

Photo Interpretation:  This association dominates the salt marshes of Fire Island and the Floyd Estate. It is fund in close proximity to Spartina alterniflora on the less-frequently flooded protions of the salt marsh. This type has a uniform tan color and is often bisected by mosquito ditches (which dry the areas further).
 

Aerial Photo Sample:

Spartina high salt marsh on right side (outlined in red), with Spartina low salt marsh and bay on the left side of photo.

Field Notes:  Dominated by Distichlis spicata (wiry appearance) or Spartina patens (matted appearance), and forming dense mats in tidal flats.  Often adjacent to Spartina alterniflora Herbaceous Alliance, which occurs closer to shore.
 

Ground Photos:

D. spicata close-up (note wiry appearance).	S. patens on left (note matted appearance), S. alternifolia on right of photo.

 

Similar Alliances:  Spartina alterniflora /(Ascophyllum nodosum) Acadian/Virginian Zone Herbaceous Vegetation: Dominated by Spartina alterniflora rather that S. patens or Distichlis spicata.  S. alterniflora is a taller, broader leaved grass than either S. patens or D. spicata. Occurs in lower salt marshes and is flooded more regularly than this alliance.  Limited to the zone between mean sea level and mean high water level.  In aerial photos, the S. alterniflora alliance appears darker than S. patens or D. spicata with a smooth texture.  Often located between this alliance and the ocean/bay.  See above photo for field comparison.