|Plymouth gentian, Plymouth pink, Plymouth rose gentian|
|Elizabeth J. Farnsworth|
The following Participating Institutions are custodians for this species in the CPC National Collection:
New England Wild Flower Society
The conservation of Sabatia kennedyana is fully sponsored.
Elizabeth J. Farnsworth contributed to this Plant Profile.
Sabatia kennedyana is a perennial, herbaceous plant bearing gorgeous, pink, daisy-like flowers on tall stems. It forms colonies along the shores of coastal plain ponds from Nova Scotia south to South Carolina. The population densities and reproduction of this species are tightly tied to fluctuating water levels in these ponds, and as such, are affected by water quality and quantity in these ponds. Populations of Sabatia kennedyana are at risk throughout its range, as humans increasingly encroach on these ponds, pollute their shores, and withdraw water.
Research and Management Summary:
A number of individuals and institutions have studied this species. Management activities are also underway to help protect and preserve Sabatia kennedyana.
Sabatia kennedyana can form rhizomatous colonies, with vertical, few-branched stems reaching 65 cm (25 inches) in height. Its 2 to 5 cm-long leaves are narrow and arrayed oppositely along the stem. The flowers, which appear from July to mid-September, are showy and large (to 5 cm in diameter), with 9 to 11 pink petals surrounding a yellow center bordered with red. The capsules are cylindrical and measure 7 to 11 mm in length.
Distribution & Occurrence
- North Carolina
- Rhode Island
- South Carolina
Sabatia kennedyana is a specialized inhabitant of coastal plain pond shores along the east coast of North America. It is known from "sandy, peaty soils and cobble beaches of streams and lakes" in the Tusket Valley of Nova Scotia, where there are at least 8 populations (Newell 1999, COSEWIC 2001). Periodic water level fluctuations tend to exclude competitively superior shrubs and other plants (Keddy 1985, Keddy et al. 1994). Ice scour and wave action also help to prevent the establishment of more invasive plant species (COSEWIC 2001). Absent from the coasts of Maine, New Brunswick, and New Hampshire, the species next appears in southeastern Massachusetts, where it attains the highest population densities in its range along sandy to peaty shores of freshwater ponds on the coastal plain (U. S. Fish and Wildlife Service 2001, MANHESP 1985). There, it occurs with other restricted members of the coastal plain plant guild, including: Eleocharis melanocarpa, Drosera filiformis, Fuirea pumila, Gratiola aurea, and Coreopsis rosea. The species occurs in similar habitats in Rhode Island (Enser 1999). The species next occurs disjunctly in Virginia and the Carolinas along river and pondshores with variable water levels. It is regarded as an obligate wetland species (USDA 2001).
|Nine sites in Nova Scotia are known, encompassing approximately 3500 plants (COSEWIC 2001). Approximately 112 occurrences in 5 counties are verified in Massachusetts as of 1985 (MANHESP 1985), with 37 additional historic occurrences. The species is reported from 4 counties in Rhode Island, 1 county in South Carolina, and 1 county in North Carolina (USDA 2001). The global population is problematic to estimate, because plant numbers fluctuate widely depending upon pond water levels, but may range to approximately 10,000.|
Conservation, Ecology & Research
Flowers are protandrous (male parts appear first), which may encourage out-crossing (Dudash 1990, Orrell 2001). Floral color and pattern varies widely among plants (Orrell 2001). Flowering is highest in years when the water level drops (COSEWIC 2001).
Possible pollinators include syrphid flies and beetles (Orrell 2001).
Studies by Dudash (1990, 1991, 1993) on the reproductive biology of the more common congener, Sabatia angularis, may be informative about inbreeding depression and pollinator limitation in S. kennedyana.
Results from mixed planting trials suggest that the species is a poor competitor for light and nutrients compared to other wetland plants, and ranks low in a competitive hierarchy along with other rare specialists of coastal plain ponds (Hill and Keddy 1992, Keddy et al. 1994, Gaudet and Keddy 1995).
The species is limited in its capacity to form seed banks (Wisheu and Keddy 1991), so population numbers may vary widely among years, especially if rhizomes do not survive disturbance.
Increased recreational use of pondshores, leading to trampling and habitat destruction
Increased water withdrawal by expanding coastal popu
COSEWIC is monitoring populations of the plant and conducting general research on the ecology of coastal plain ecosystems (COSEWIC 2001).
Detailed hydrological studies of the coastal plain ponds of Barnstable are underway at The Massachusetts Chapter of The Nature Conservancy (McHorne 1996)
The Norcross Sanctuary in Monson, Massachusetts, also has Sabatia kennedyana in its rare plant collection
Graduate student, Lelia Orrell (University of Massachusetts at Boston), is performing extensive research on the metapopulation dynamics, reproduction, and population genetics of Sabatia kennedyana.
Professor Paul Keddy, now with Southeastern Louisiana University, has published several papers on the status and ecology of Sabatia kennedyana in Nova Scotia.
Graduate student, Stephen Craine (Tufts University, Medford, Massachusetts) is conducting research on factors influencing the invasion of coastal plain ponds by pitch pine on Cape Cod.
Graduate student Nina Coleman (University of Massachusetts at Amherst) is studying the effects of removing the invasive grass, Phragmites australis from coastal plain ponds on Cape Cod in terms of the recovery of several rare plant species
This showy plant is propagated and sold by the Lazy S'S Farm Nursery in Barboursville, Virginia and by Plant Delights Nursery, Raleigh, North Carolina.
COSEWIC and partner conservation organizations in Nova Scotia are developing landowner education programs to encourage protection of coastal plain ponds and more sensitive use of these critical areas by all-terrain vehicles (Wilson 1997, Phinney 1999, COSEWIC 2001)
The town of Fall River, which supports an occurrence of Sabatia kennedyana and numerous coastal plain ponds, has developed an Open Space and Recreation Plan that can serve as a potential model for other communities with similar conservation concerns.
Myra, M. Abstract presented: Reproductive biology of the Plymouth gentian (Sabatia kennedyana). Atlantic Universities Undergraduate Biology Conference; Mount Allison University, Sackville, New Brunswick, Canada. 2000.