The following Participating Institutions are custodians for this species in the CPC National Collection:
The Lady Bird Johnson Wildflower Center
Mercer Arboretum and Botanic Gardens
San Antonio Botanical Garden
The conservation of Hibiscus dasycalyx is partially sponsored.
Dave Berkshire contributed to this Plant Profile.
The Neches River rose mallow is a federally listed candidate endangered native Hibiscus that now only exists in three wetlands in E. Texas. This Hibiscus has delicate slender finely divided leaves on long, arching 3-7 foot long stems. The creamy white flowers are 3-6 inches wide with dark burgundy eyes, bear five 2-4 inch long petals and appear from June through August. Occasionally the flowers bear pink petals. Plants often bloom into October depending upon water availability. This Hibiscus is distinguished from other native Hibiscus in that its flower has a densely pubescent calyx and bracteoles and its mature seeds are densely pubescent as well. Budding and leafing normally occur late March-April and fruits are present from July through November.
Distribution & Occurrence
Found in East Texas Prairie wetlands in areas of open sun. Populations are generally located within floodplains of permanent streams or rivers (Angelina, Neches and Trinity Rivers), etc. that flood at least once a year. Bases of plants normally in standing water early in the growing season, with water levels dropping, but never drying out completely until late in the growing season. Some populations remain wet throughout much of the year. Groundwater is no more than 5 feet below the surface (Nemec, 2000a-c). Occurs in the marshes along Neches River, borrow pits along highway and in hydric soils in marshland complexes.
|This species was listed as Threatened in Sept. 2013. Presently, three confirmed populations exist. In 1999, two sites one bearing 8 plants, the other 200 plants in Houston County. Trinity County held three sites in 1999 at 35 plants, 17 plants and 300 plants. One plant exists in Cherokee county although more plants (pending ID) may exist in this site (Nemec 2000c). One possible location in Harrison Co. (this is from a herbarium specimen-may not still be extant, location is vague). Four total sites were listed for year 2000, with one protected by a conservation agreement in Trinity County (Nemec, 2000c).|
Conservation, Ecology & Research
Genus is host plant for Hairstreak butterflies.
Habitat has been impacted by drainage or filling of floodplain depressions and oxbows.
Mercer staff and volunteers maintain as a permanent educational exhibit of Neches River Rose Mallow within our Endangered Species Garden. The Endangered Species Garden, established in 1994 with support from Star Enterprises, displays rare native plants for the public to view year-round. In Spring 2002, the River Oaks Garden Club of Houston (ROGC), TX provided a generous gift to begin the expansion and renovation of Mercers Endangered Species Garden.
Mercer Arboretum and Botanic Gardens maintains a seed bank of this species. Banked wild-collected seed of this species date to 1993. Mercer also banks subsets of rare seeds collected from field surveys and from propagation work with our collaborating CPC institution, the Lady Bird Johnson Wildflower Center, Austin, TX and the National Center for Genetic Resources Preservation (NCGRP) in Ft. Collins, CO (formerly called the National Seed Storage Laboratories).
Plants produced for educational display gardens or for specific restoration and reintroduction projects are produced within Mercers nursery greenhouses and within our Conservation Area. The Conservation Area provides secure, raised beds for mass propagation of plants/seeds. Each bed is provided with independently controlled irrigation and substrates that meet the unique requirements for each species. Populations are propagated separately to insure genetic purity.
Reintroductions of ~700 of these plants into David Crockett National Forest, Trinity County, occurred in April of 2000. Dr. David Creech, staff and students of Stephen F. Austin State University, Nacogdoches, TX propagate this species for reintroduction. Excellent survival & flowering occurred in summer 2000.
Avoid site disturbances that affect drainage of the sites or conversion of sites for agricultural, urban or highway development.
Continue genetic research (Klips 1995). Interspecific hybridization, namely with H. laevis (syn: H. militaris), needs to be addressed. As this species is a candidate species, maintenance of genetic integrity, documentation of provenance and gene banking is essential.
Rescue and maintain populations under threat.
As this species is a candidate species, maintenance of genetic integrity, documentation of provenance and gene banking is essential.
Correll, D.S.; Correll, H.B. 1975. Aquatic and wetland plants of southwestern United States, 2 vols. Stanford, Calif.. Stanford University Press.
Nixon, E.S.; Cunningham, B.L. 1985. Trees, shrubs, and woody vines of East Texas. Nacogdoches, TX: B.L. Cunningham Productions. 240p.
Poole, J.M.; Carr, W.R.; Price, D.M.; Singhurst, J.R. 2007. Rare Plants of Texas. College Station, Texas. Texas A&M University Press. 640p.