Distribution: Scrub blazing star is largely restricted to the Lake Wales Ridge in Polk and Highlands Counties, although one population is known from the Winter Haven Ridge in Polk County (USFWS 1999).

Habitats: Scrub blazing star occurs almost exclusively on xeric white sands in rosemary and oak scrub and scrubby flatwoods. It occupies habitats with both relatively short (scrubby flatwoods < 10 years) and relatively long (rosemary scrub > 20 years) fire return intervals.

Life History: Scrub blazing star is a perennial herb that annually produces one to several flowering stems from a rosette of narrowly elliptical leaves. Flowering stems are usually about 1 m in height and bear several to many flowering heads of 20-25 conspicuous rose-pink flowers attractive to butterflies. The fruit is a typical composite achene with a pappus of fine hairs. Flowering stems senesce and die following seed dispersal. Production of flowering stems does not seem to occur in plants younger than two years old. Plants are long-lived, with a documented age of at least seven years (Menges and Weekley 2003)

Phenology: Seedlings and resprouting adults are represented aboveground by rosettes that emerge in late winter/early spring (Herndon 1999). Flowering stems begin to develop in late spring and flowering takes place from July through November, usually peaking in late August/early September. Seed heads mature throughout the late summer and into the fall. Seedling recruitment appears to be rare but is difficult to detect due to the small size of seedling rosettes.

Breeding System and Pollination: Unlike such familiar composites as the daisy, the flowering heads of scrub blazing star lack ray flowers. The five-lobed tubular disc flowers are perfect and otherwise typical of the Aster family in their unusual means of pollen presentation (Zomlefer 1989). The five fused anthers form a cylinder around the developing style. As the style elongates, it collects pollen on the backs of its two stylar arms and, as it emerges from the floral tube, pollen is presented. Later, the stylar arms extend, exposing their stigmatic upper surfaces for the reception of pollen via insects that have visited flowers on other scrub blazing star plants. This is crucial because scrub blazing star is self-incompatible (Evans et al. 2003). Butterflies are the most obvious pollinators of scrub blazing star based both on floral characters (showy tubular flowers) and on observation of floral visitors.

Genetics: In keeping with its self-incompatibility and its pollination by butterflies, scrub blazing star displays a higher degree of within-population genetic variation than most co-occurring scrub endemics (Dolan et al. 1999, Menges et al. 2001).

Population Dynamics: Scrub blazing star resprouts postfire, but since aboveground population sizes fluctuate annually due to belowground dormancy, it difficult to determine the extent to which some plants may be killed by fire (Weekley and Menges in press). In unburned populations, both seedling recruitment and adult mortality appear to be rare.

Interesting Facts: Scrub blazing star is one of 14 species of Liatris in Florida, three of which are endemic to the state (Wunderlin 1998). It is distinguished from several other white sand endemics in its broader microhabitat tolerance (it is not a gap specialist), in its ability to resprout postfire, and in its occasional dormancy (i.e., live plants do not necessarily appear aboveground every year). Scrub blazing star is also unusual among scrub endemics in being butterfly-pollinated. The aboveground parts of scrub blazing stars contain at least two novel terpenes, although their function is not known (Lu et al. 1994).

Data Collected by Archbold Biological Station’s Plant Ecology Lab: Members and associates of the Plant Ecology Lab have collected data on several aspects of the biology and ecology of scrub blazing star. Herndon (1999) censused several populations from 1993-1995 and found that they were demographically stable due to low rates of both adult mortality and seedling recruitment. Dolan et al. (1999), investigating populations across the known range, found that scrub blazing star is unusual among Lake Wales Ridge endemics in having low population densities and high within-population genetic variation. Weekley and Menges (in press) discovered that scrub blazing star appears to be a relatively weak postfire resprouter compared to other resprouting scrub plants. Evans et al. (2003) elucidated the breeding system of scrub blazing star and concluded that it is perhaps pollinator-limited. Hunter and Menges (2002) found that unlike most rosemary scrub specialists, germination of scrub blazing star is unaffected by the allelopathic effects of Florida rosemary (Ceratiola ericoides). And thanks to the work of other researchers, we now know that both vertebrate (Kettenring 1999) and invertebrate (Weekley 1998, Herndon 1999, Goss unpubl. data) herbivores negatively impact reproductive output by removing or damaging flowering stems, inflorescences or developing achenes.

     The Plant Ecology Lab has been collecting demographic data on populations at Archbold and at Lake Wales Ridge State Forest since 2000 and is a conducting a series of lab and field experiments to explore the fire ecology and seed/seedling ecology of scrub blazing star.

Data Availability: The data are not yet available on line.

Contact Person: Carl W. Weekley

1. Dolan, R.W., R. Yahr, E.S. Menges, and M.D. Halfhill. 1999. Conservation implications of genetic variation in three rare species endemic to Florida rosemary scrub. American Journal of Botany 86: 1556-1562.
2. Evans, M.E.K., E.S. Menges and D.R. Gordon. 2003. Reproductive biology of three sympatric endangered plants endemic to Florida scrub. Biological Conservation 111: 235-246.
3. Herndon, A. 1999. Life history of Liatris ohlingerae (Asteraceae), an endangered plant endemic to the Lake Wales Ridge, Florida. Florida Fish and Wildlife Conservation Commission, Tallahassee, FL. 46 pp.
4. Hunter, M.E. and E.S. Menges. 2002. Allelopathic effects and root distribution of Ceratiola ericoides (Empretraceae) on seven rosemary scrub species. American Journal of Botany 89: 1113-1118.
5. Kettenring, K. 1999. Effects of herbivory on reproduction of Liatris ohlingerae (scrub blazing star). Intern report. Archbold Biological Station, Lake Placid, FL.
6. Lu, T.S., C.L. Cantrell, D. Vargas, F.R. Fronczek, S.G. Franzblau, N.H. Fischer. 1994. Terpenes from Liatris ohlingerae. Phytochemistry 37:1295-1299.
7. Menges, E.S. and C.W. Weekley. 2003. Continuation of demographic research on four state-listed Lake Wales Ridge endemic plants. Final report to the Florida Department of Plant Industry, Endangered and Threatened Native Flora Conservation Program. 75 pp.
8. Menges, E.S., R.W. Dolan, R. Yahr, and D.R. Gordon. Comparative genetics of seven plants endemic to Florida’s Lake Wales Ridge. Castanea 66: 98-114.
9. US Fish and Wildlife Service. 1999. Multi-species recovery plan for the threatened and endangered species of South Florida. US Fish and Wildlife Service, Vero Beach, FL.
10. Weekley, C.W. 1998. Demography and reproductive performance of Liatris ohlingerae at Lake Wales Ridge State Forest. Unpublished report to the Florida Division of Forestry, Tallahassee, FL. 15 pp.

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