The following Participating Institutions are custodians for this species in the CPC National Collection:
North Carolina Botanical Garden
Brooklyn Botanic Garden
Bok Tower Gardens
The conservation of Schwalbea americana is fully sponsored.
Elizabeth J. Farnsworth contributed to this Plant Profile.
A tall, perennial herb in the figwort family, this plant is distinguished by its large, purplish-yellow, tubular flowers. Schwalbea americana is a hemiparasite that feeds from the roots of a range of associated woody species. Once known historically from the coastal plain extending from Massachusetts to Florida, the species now only occurs at 51 sites and 15 distinct populations in New Jersey, the Carolinas, Georgia, Florida, and Mississippi, where it is threatened by residential development, road-building, inappropriate mowing regimes, over-collection, and fire suppression.
Research and Management Summary:
A number of individuals and institutions have studied many aspects of the ecology of this plant, including how to best manage for the species where it occurs.
Schwalbea americana is an erect, perennial herb with unbranched stems that grows to a height of 80 cm (30 inches). It is densely but minutely hairy throughout, including the flowers. The alternate, 2-4 cm-long leaves are lance-shaped, untoothed, and clasp the stem. The irregular, tubular flowers, which are yellow-purple and 15-22 mm long, subtended by two small leaves (bracts) and borne singly on short stalks (pedicels). The fruit is a stout capsule 10-12 mm long, enclosed in a loose-fitting sac-like structure that gives the plant its common name, chaffseed. The green seeds are 2-6 mm long, straight, and narrow (Small 1933, Pennell 1935, Musselman and Mann 1978, Vincent 1982, Kral 1983, Gleason and Cronquist 1991).
Distribution & Occurrence
- New Jersey
- New York
- North Carolina
- South Carolina
Schwalbea americana occurs in acidic, sandy or peaty soils in open pine flatwoods, longleaf pine/oak sandhills, streamhead pocosins, pitch pine lowland forests, seepage bogs, palustrine pine savannahs, in ecotonal areas between peaty wetlands and xeric sandy soils (NatureServe 2001). Historically, the species is known from inland sandplains in Albany, New York and central Massachusetts. The species is regarded as a facultative wetland plant (USDA Plants National Database 2001); individual plants sometimes occur in drier upland communities, but rarely inhabit inundated wetlands (Rawinski and Cassin 1986).
Associated plant communities are typically species-rich, and dominated by grasses and sedges. Plant genera reported to occur with Schwalbea americana in the Southeast include grass species of Andropogon, Aristida, Panicum, and Paspalum; sedge species of Carex, Dichromena, Fimbristylis, Rhynchospora, Scleria; monocot species of Aletris, Calopogon, Eriocaulon, Juncus, Lachnocaulon, Xyris; and dicot species of Asclepias, Buchnera, Erigeron, Eryngium, Helenium, Heterotheca, Orbexilum, Phlox, and Polygala. In wetter habitats, species of Cliftonia, Gaylussacia, Ilex, Lyonia, Leucothoe, Myrica, and Vaccinium occur as associates (Fernald 1939, Kral 1983, NatureServe 2001).
|51 populations are extant, according to NatureServe (2001), composed of 1 in New Jersey, 18 in North Carolina, 26 in South Carolina, 5 in Georgia, and 1 in Florida. Many of these populations have been discovered in the past decade. However, this number is only a fraction of the 68 or more populations recorded historically (U. S. Fish and Wildlife Service 1992, NatureServe 2001). At least twelve of the populations in 1992 had less than 100 plants present (U. S. Fish and Wildlife Service 1992); thus, the total North American population probably ranges from 1,000 to 10,000 plants at most.|
Conservation, Ecology & Research
Like many members of its family, the species is a hemiparasite, forming haustorial connections to the roots of living plants and deriving nutrients from them (Musselman and Mann 1977, Kirkman and Musselman 2000).
The plant flowers from April to June in the southern states and from June to mid-July in New Jersey (Johnson 1988), and fruits mature from mid-summer to October.
Bees are likely pollinators of this taxon, given the tubular structure and color of its flowers (Pennell 1935).
Conversion of coastal plain habitat for residential and agricultural development
Inappropriate mowing regimes (timed poorly with respect to flowering time), especially at the one existi
Hemiparasitic relationships and haustorial anatomy have been elucidated by Musselman and Mann (1977, 1978) and Kirkman and Musselman (2000).
Seed anatomy has been documented by Musselman and Mann (1976).
Extensive field surveys have been undertaken to locate previously unknown populations of the plant (Rawinski and Cassin 1986), and several new occurrences have been noted since the original listing of the species in 1992. However, it is clear that the species occupies only a fraction of historical and available habitat.
The New England Wild Flower Society has germinated limited numbers of seed from Schwalbea americana during trials in 1982. Seed sown on the soil surface and overwintered outdoors showed the best germination rate. However, seedlings grown without host plants did not survive (Brumback 1989), and survival has been poor in plantings even with a potential host plant, little bluestem.
Propagation and reintroduction of Schwalbea americana is described by Obee and Cartica (1997), but appears to have also met with mixed success.
The Chattahoochee Nature Center (Roswell, Georgia) maintains Schwalbea americana in their greenhouse.
Improved mowing regimes are being developed in New Jersey (USFWS 1992) and New Jersey (Rawinski and Cassin 1986).
Jordan et al. (1995) present a review of recommended management for the red-cockaded woodpecker and the associated rare species (including Schwalbea americana) that co-occur in its habitat.
Obee (1993) describes monitoring and seed collection of Scwalbea americana at one site in New Jersey.
Studies of pollination and other facets of reproduction that could influence population persistence.
Studies to determine ecological factors that limit recruitment and establishment of populations.
Increased intensity and frequency of population monitoring (NatureServe 2001) in order to understand demographics and reasons for the decline of protected populations.
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