CPC National Collection Plant Profile

Schwalbea americana

Copyright Hugh and Carol Nourse

Heading for profile page
CPC Home Join now
About CPC
CPC National Collection
Conservation Directory Resources
Invasive Plant Species Plant News
Plant Links Participating Institutions
Search CPC
Search    Alphabetical List    Reference Finder    CPC Home

CPC National Collection Plant Profile

Schwalbea americana

Common Names: 
American chaffseed, Chaffseed
Growth Habit: 
CPC Number: 


Profile Links
 Fish & WildLife
 Forest Service

Schwalbea americanaenlarge
Photographer: Copyright Hugh and Carol Nourse

Schwalbea americanaenlarge
Photographer: Copyright Hugh and Carol Nourse

Schwalbea americana is Fully Sponsored
Primary custodian for this plant in the CPC National Collection of Endangered Plants is: 
Elizabeth J. Farnsworth contributed to this Plant Profile.

Schwalbea americana

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.

Plant Description:
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

State Range
New Jersey
New York
North Carolina
South Carolina
State Range of  Schwalbea americana
  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).

  Schwalbea americana is formerly known from the Atlantic and Gulf coastal plain extending from Cape Cod, Massachusetts south to Texas. Inland sandplain populations are also historically reported from interior Massachusetts, New York, and Kentucky. Currently, the species is restricted to Florida, Georgia, North and South Carolina, and New Jersey.

Number Left
  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.


Global Rank:  
Guide to Global Ranks
Federal Status:  
Guide to Federal Status
Recovery Plan:  

State/Area Protection
  State/Area Rank Status Date  
  Alabama S1 10/3/1991  
  Connecticut SH 8/29/1983  
  Delaware SX 12/14/2001  
  Florida S1 E 4/1/1998  
  Georgia S1 E 10/1/2001  
  Kentucky SH 1/1/2000  
  Louisiana SH 7/6/1996  
  Maryland SX X 4/30/2001  
  Massachusetts SX 6/2/1989  
  Mississippi S1 1/1/2000  
  New Jersey S1 E 9/1/2001  
  New York SX U 4/1/2001  
  North Carolina S1 E 1/1/1999  
  South Carolina S2 E 5/1/2000  
  Tennessee SX 4/1/2001  
  Texas SR 6/15/1992  
  Virginia SH 3/1/2001  

Conservation, Ecology & Research

Ecological Relationships
  Schwalbea americana is a perennial species that can persist permanently in an area, provided the habitat is kept relatively open by fire, mowing, artillery fire (at one military base), and other periodic disturbance (USFWS 1992).

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).

  As articulated by the U. S. Fish and Wildlife Service (1992):

Conversion of coastal plain habitat for residential and agricultural development
Inappropriate mowing regimes (timed poorly with respect to flowering time), especially at the one existing site in New Jersey
Fire suppression, leading to succession by woody vegetation that outcompetes Schwalbea americana for light
Over-collection and trampling by botanical enthusiasts

Current Research Summary
  The effects of prescribed burns on Schwalbea americana have been investigated by Kirkman et al. (1998).

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.

Current Management Summary
  The effectiveness of using controlled burns to foster Schwalbea americana is being explored at several sites throughout its range (Kirkman et al. 1998).

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.

Research Management Needs
  A number of studies are needed, including:

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.

Ex Situ Needs
  Improved methods for germination and maintaining viable plants need to be developed.


Books (Single Authors)

1979. Endangered and Threatened Plants and Animals of Virginia. Blackburg, Virginia: Virginia Polytechnic Institute and State University. 665p.

Braun, E.L. 1943. An annotated catalog of spermatophytes of Kentucky. Cincinnati, Ohio: Swift Co.

Broome, C.R.; Tucker, A.O.; Reveal, J.L.; Dill, N.H. 1979. Rare and Endangered Vascular Plant Species in Maryland. Newton Corner, MD: U.S. Fish and Wildlife Service. 64p.

Coile, N.C. 2000. Notes on Florida's Regulated Plant Index (Rule 5B-40), Botany Contribution 38. Gainesville, Florida: Florida Dept. of Agriculture and Consumer Services, Division of Plant Industry.

Correll, D.S.; Johnston, M.C. 1970. Manual of the vascular plants of Texas. Renner: Texas Research Foundation. 1881p.

FNAI. 2000. Field Guide to the Rare Plants and Animals of Florida online. Florida Natural Areas Inventory.

Hough, M.Y. 1983. New Jersey wild plants. Harmony, NJ: Harmony Press. 414p.

Jones, S.B., Jr.; Coile, N.C. 1988. The distribution of the vascular flora of Georgia. Athens, GA: University of Georgia. 230p.

MacRoberts, D.T. 1989. A documented checklist and atlas of the vascular flora of Louisiana. Bulletin of the Museum of Life Sciences, No. 7. Shreveport, Louisiana: Louisiana State University.

Massey, A.B. 1961. Virginia Flora: An Annotated Catalog of Plant Taxa Recorded as Occurring in Virginia. Blacksburg, Virginia: Virginia Agricultural Experiment Station. 251p.

Pennell, F.W. 1935. The Scrophulariaceae Of Eastern Temperate North America. Philadelphia, Pennsylvania: Academy of Natural Sciences. 650p.

Seymour, F.C. 1989. The flora of New England. A manual for the identification of all vascular plants including ferns and their allies growing without cultivation in New England. Boston: Boston Museum Science. 611 + appendixp.

Small, J.K. 1933. Manual of the southeastern flora. New York, NY: Hafner Publishing Company. 1505p.

Terwilliger, K. 1991. Virginia's endangered species. Blacksburg, VA: McDonald and Woodward Publishing Co. 170p.

Books (Sections)

Fairbrothers, D.E. 1979. Endangered, threatened and rare vascular plants of the Pine Barrens and their biogeography. In: Forman, R.T.T., editor. Pine Barrens: ecosystem and landscape. Academic Press. New York. p 395-405.

Conference Proceedings

Campbell, J.J.; Taylor, D.D.; Medley, M.E.; Risk, A.C. Floristic and historical evidence of fire-maintained, grassy pine-oak barrens before settlement in southeastern Kentucky. Fire and the environment: ecological and cultural perspectives, proceedings of an international symposium; March 20-24, 1990; Knoxville, Tennessee. In: Nodvin, S. C.; Waldrop, T. A., editors. 1991. Southeastern Forest Experiment Station, Asheville, N.C. p 359 - 375.

Electronic Sources

(2002). Atlas of Florida Vascular Plants. [Web site] University of South Florida Institute for Systematic Botany. http://www.plantatlas.usf.edu/isb/default.htm. Accessed: 2008.

(2002). NC-ES Plant profiles. [Web pages] North Carolina Ecological Services--U.S. Fish & Wildlife Services--Southeast Region 4. http://nc-es.fws.gov/plant/plant.html. Accessed: 2002.

NatureServe. (2008). NatureServe Explorer: An online encyclopedia of life [web application]. [Internet].Version 7.0. NatureServe, Arlington, Virginia. http://www.natureserve.org/explorer. Accessed: (June 17, 2008).

Journal Articles

Braun, E.L. 1936. Notes on Kentucky plants. I. Castanea. 1: 41-45.

Brumback, W.E. 1989. Notes on propagation of rare New England species. Rhodora. 91: 154-162.

Determann, R.; Kirkman, L.K.; Nourse, H. 1997. Plant conservation by propagation: the cases of Macranthera and Schwalbea. Tipularia. 12: 2-12.

Fernald, M.L. 1939. The flora of tidewater Virginia. Rhodora. 41: 469.

Frost, C.C.; Musselman, L.J. 1987. History and vegetation of the Blackwater Ecologic Preserve. Castanea. 52: 16-46.

Godt, M.J.W.; Hamrick, J.L. 1998. Low allozyme diversity in Schwalbea americana (Scrophulariaceae), an endangered plant species. Journal of Heredity. 89, 1: 89-93.

Helton, R.C.; Kirkman, L.K.; Musselman, L.J. 2000. Host preference of the federally endangered hemiparasite Schwalbea americana L. (Scrophulariaceae). Journal of the Torrey Botanical Society. 127, 4: 300-306.

Jennison, H.M. 1935. Notes on some plants of Tennessee. Rhodora. 34: 323.

Kirkman, L.K.; Drew, M.B.; Edwards, D. 1998. Effects of experimental fire regimes on the population dynamics of Schwalbea americana L. Plant Ecology. 137, 1: 115-137.

Kondo, K.; Musselman, L.J.; Mann, W.F., Jr. 1978. Karyo morphological studies in some parasitic species of the Scrophulariaceae, Pt. I. Brittonia. 30: 345-354.

Musselman, L.J.; Mann, W.F., Jr. 1976. A survey of surface characteristics of seeds of Scrophulariaceae and Orobanchaceae using scanning electron microscopy. Phytomorphology. 26: 370-378.

Musselman, L.J.; Mann, W.F., Jr. 1977. Parasitism and haustorial structure of Schwalbea americana, Scrophulariaceae. Beitr. Biol. Pflanz. 53: 309-331.

Obee, E.M.; Cartica, R.J. 1997. Propagation and reintroduction of the endangered hemiparasite Schwalbea americana (Scrophulariaceae). Rhodora. 99, 898: 134-147.

Reveal, J.L.; Broome, C.R. 1981. Minor nomenclatural and distributional notes on Maryland, USA vascular plants with comments on the states proposed endangered and threatened species. Castanea. 46: 50-82.

Reveal, J.L.; Broome, C.R. 1982. Comments on the proposed endangered and threatened vascular plants of Maryland, USA. Castanea. 47: 191-200.

Sorrie, B.A. 1987. Notes on the rare flora of Massachusetts. Rhodora. 89, 858: 113-196.

Townsend, J.F. 1997. An Unusual Concentration of the Federally Endangered Schwalbea americana L. (Scrophulariaceae) in South Carolina. Castanea. 62, 4: 281.

USFWS. 1992. Endangered status for Schwalbea americana (American chaffseed). Federal Register. 57, 189: 44703 - 44708.

USFWS. 1992. Final Listing Rules Approved for 21 Species During July/October 1992. Endangered Species Technical Bulletin. 17, 9-11: 9.

Wisheu, I.C.; Keddy, C.J.; Keddy, P.A. 1994. Disjunct Atlantic Coastal Plain species in Nova Scotia - distribution, habitat and conservation priorities. Biological Conservation. 68: 217-224.


Johnson, R.T. 1988. Draft of an Element Stewardship Abstract (Schwalbea americana). Pottersville, New Jersey: New Jersey Field Office of The Nature Conservancy. Unpublished report.

Jordan, R.A.; Wheaton, K.S.; Weiher, W.M. 1995. Integrated Endangered Species Management Recommendations for Army Installations in the Southeastern United States: Assessment of Army-wide Management Guidelines for the Red-cockaded Woodpecker and Associated Endangered, Threatened and Candidate Species, final draft report prepared for the Natural Resources Division, USACERL. Chapel Hill, North Carolina: The Nature Conservancy, Southeast Regional Office.

Kirkman, L.K.; Drew, M.B. 1993. Season of fire effects on the federally endangered Schwalbea americana: preliminary results. Joseph W. Jones Ecological Research Center, Ichauway, and the Georgia Institute of Ecology. Unpublished.

Kral, R. 1983. A report on some rare, threatened, or endangered forest-related vascular plants of the South. Athens, GA: U.S. Dept. of Agriculture Forest Service. p.1305. U.S. Dept. of Agriculture Forest Service Technical.

Musselman, L.J.; Mann, W.F., Jr. 1978. Root parasites of southern forests. Alexandria, LA: Southern Forest Experiment Station, U.S. Forest Service. p.76. General Technical Report SO-20.

Obee, E.M. 1993. Management and monitoring of Schwalbea americana at Whitesbog. Trenton, New Jersey: New Jersey Department of Environmental Protection and Energy, Division of Parks and Forestry, Office of Natural Lands Management.

Rawinski, T.; Cassin, J. 1986. Final status survey reports for 32 plants submitted to the U.S. Fish & Wildlife Service. Boston: The Nature Conservancy Eastern Heritage Task Force.

Rayner, D.A. 1986. Report on Schwalbea americana: Population status and trends for The Nature Conservancy. Columbia, South Carolina: South Carolina Wildlife and Marine Resources Department.

Schafale, M.P.; Weakley, A.S. 1990. Classification of the natural communities of North Carolina: third approximation. Raleigh, North Carolina: North Carolina Natural Heritage Program, North Carolina Dept. of Environment, Health and Natural Resources.

TNC. 1993. Rare and endangered plant survey and natural area inventory of Fort Bragg and Camp MacKall military reservations, North Carolina. Sandhills Field Office: Final report by The Nature Conservancy.

USFWS. 1995. American Chaffseed (Schwalbea americana) Recovery Plan. Hadley, Massachusetts: U.S. Fish and Wildlife Service. p.62.

Yurlina, M. 1998. Management and Monitoring of Schwalbea americana in New Jersey. Trenton, NJ: State of New Jersey, Department of Environmental Protection. p.30. Confidential Report.


Vincent, K.A. 1982. Scrophulariaceae of Louisiana. [M.S. thesis]: University of Southwestern Louisiana. Lafayette. 234p.

  This profile was updated on 9/28/2010
New Mexico
North Dakota
South Dakota
South Carolina
North Carolina
West Virginia
New Jersey
Rhode Island
New Hampshire
New York
New York