A globally rare coastal salt pond marsh system at Odiorne Point State Park, Rye, New Hampshire.

Abstract Vegetation patterns in the coastal salt pond marsh system at Odiorne Point State Park in Rye, New Hampshire, the state's only viable example, are described based on recent surveys and historical data. Four natural communities occur within the system: coastal salt pond flat, coastal salt pond emergent marsh, coastal salt pond meadow marsh, and highbush blueberry–winterberry shrub thicket. The first three communities are newly described in New Hampshire and the northeastern US coastline. A total of 69 native or naturalized vascular plant taxa from 54 genera and 33 families have been documented in the system at Odiorne Point between 1967 and 2011. The families best represented were Cyperaceae (10 taxa), Poaceae (9 taxa), and Asteraceae (6 taxa); the largest genera were Eleocharis (4 taxa), Hypericum (4 taxa), and Agrostis (3 taxa). In 2011, only 35 of the 69 plant taxa were documented; a difference that can be attributed, at least partially, to the variable nature of hydrologic and salinity influenc...