Hedyotis purpurea var. montana
|mountain bluet, Roan Mountain bluet|
The following Participating Institutions are custodians for this species in the CPC National Collection:
The North Carolina Arboretum
The conservation of Hedyotis purpurea var. montana is fully sponsored.
Michael Kunz contributed to this Plant Profile.
Roan Mountain bluet is a rare endemic found on a few mountains in the Southern Appalachians. A member of the coffee family (Rubiaceae), Roan Mountain bluet produces heterostylus flowers (two different length styles). This species is a compact clump forming perennial herb and produces flat top clusters of one to four deep red-purple flowers from May to September. The flower color helps distinguish H. purpurea var. montana from the more common H. purpurea var. purpurea with flowers of blue-purple to white.
The US Fish and Wildlife Service recognize Roan Mountain bluet as a restricted variety of Hedyotis purpurea. While its morphological distinctness is clear, the taxonomic position is disputed (US Fish and Wildlife Service, 1996). Roan Mountain bluet is also known as Houstonia montana. Noted by Asa Gray in 1841 as a dwarf form and described by J.K. Small in 1903 as Houstonia montana, taxonomic differences have ensued over the generic placement, altering between Hedyotis and Houstonia, and recognition at the varietal level or designation of full species rank. See Terrell (1959), Yelton (1974) and Terrell (1978) for more taxonomic information. The current opinion places Roan Mountain bluet as Houstonia montana (US Fish and Wildlife 1996, Weakley in preparation 2008).
Distribution & Occurrence
- North Carolina
Roan Mountain bluet grows at high elevation (above 4,200 ft) in the shallow soils and crevices of cliffs and outcrops and on thin rocky soils of grassy balds. This species is associated acidic soils and with Fraser fir (Abies fraseri) and red spruce (Picea rubens) forests. Roan Mountain bluet is typically found with five co-occurring species, Saxifraga michauxii, Athyrium filix-femina spp. asplenioides, Paronychia argycoma, Heuchera villosa and Carex misera, seventy-five percent of the time (US Fish and Wildlife 1996).
|Roan Mountain bluet is known from twelve populations with all but one subpopulation located in NC (Euliss et al. 2007).|
Conservation, Ecology & Research
Roan Mountain bluet is a poor competitor for light and unlikely to grow with other vegetation taller than 50cm (Wiser et al. 1998).
The ability of Roan Mountain bluet to survive on grassy slopes is dependant on rapid early season growth, which also suggests the importance of genetic variation among populations (Euliss et al. 2007).
Succession and other vegetation changes.
Possibly air pollution and exotic insects change the surrounding spruce-fir forests.
Protect populations on private land.
Reducing visitor access to sites to limit trampling.
NatureServe. (2002). Southern Appalachian Species Viability Project. A partnership between the U.S. Forest Service-Region 8, Natural Heritage Programs in the Southeast, NatureServe, and independent scientists to develop and review data on 1300+ regionally
Weakley, A.S. (2008). Flora of the Carolinas, Virginia, Georgia, and surrounding areas.. [pdf]. http://herbarium.unc.edu/flora.htm. Accessed: 2008.