|Photo was taken by Gil Nelson|
|Division:||Magnoliophyta - Flowering plants|
|Class:||Magnoliopsida - Dicotyledons|
|Natural range of Aureolaria flava from USDA NRCS Plants Database.|
Common name: Smooth yellow false foxglove
Varieties: Gerardia flava Linnaeus var. flava; Gerardia flava var. reticulata (Rafinesque) Cory; A. flava ssp. typica Pennell; Gerardia flava Linnaeus var. macrantha (Pennell) Fernald
In the genus Aureolaria, the plants are either annual or perennial. They are parasitic on the roots of Quercus (oaks) and turn black when dried. The leaves are opposite or subopposite and branch from the upper portion of the stem (cauline). The flowers are showy, the calyx is 5-parted, the lobes can be shorter or longer than the tube. The flower is yellow in color, bilabiate, and 5-parted. The tube is bell-shaped with spreading lobes. There are 4 stamens, didynamous, and the filaments are flattened with the 2 longer more or less lanose. The anther sacs are basally awned. The stigma is capitate and protruding.
Specifically for A. flava, the plant is perennial and parasitic on Quercus alba (white oaks). The stems are glabrous and grow to approximately 2 or more meters. The glabrous leaves are lanceolate or elliptic lanceolate, the upper portion is usually entire or serrate and the lower portion is usually pinnately lobed to parted, and they grow to approximately 7 - 17 cm long and 1.5 - 7 cm wide. The flowers and pedicels are glabrous, 4 - 25 mm long at the anthesis, and curve upward. The calyx lobes are lanceolate to triangular, equaling or slightly longer than the tubes which are entire, and are 3 - 5 mm long. The flower is 3 - 5 cm long. The capsules are glabrous.
This species is a hemiparasitic plant. It uses specialized roots called haustoria that attach to the roots of hosts to transport sugars and proteins. Since it is a hemiparasitic plant, it still has green tissues and preforms photosynthesis. Quercus species are one of the major host plants.
Habitats include cliffs, balds, ledges, ridges, pine-oak woods and loamy sand in oak-hickory on upper slopes of steepheads in shaded areas. It also can be found in areas of human disturbance such as on the edges of trails and slopes of impoundments. This species is a hemiparasitic plant which often times uses species of Quercus as its host.
The yellow flowers are bisexual, weakly bilaterally symmetrical and have a superior ovary. Flowering occurs summer through fall from August to September; and September to October.. It has been observed flowering in north Florida in May and July.The fruit is a capsule.
Populations of Aureolaria flava have been known to persist through repeated annual burns.
Aureolaria flava is known to be pollinated by bumblebees.
Conservation, cultivation, and restoration
References and notes
- Weakley, A.S. 2020. Flora of the Southeastern United States. Edition of 20 October 2020. University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
- Radford, Albert E., Harry E. Ahles, and C. Ritchie Bell. Manual of the Vascular Flora of the Carolinas. 1964, 1968. The University of North Carolina Press. 957-8. Print.
- []Go Botany. Accessed: April 1, 2016
- Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: June 2014. Collectors: L. C. Anderson, B. Boothe, M. Boothe, V. Craig, R. K. Godfrey, H. Roth, and R.A. Norris. States and Counties: Florida: Gadsden, Leon, and Liberty.
- Belofsky, G., M. D. Bowers, et al. (1989). "Iridoid glycosides of Aureolaria flava and their sequestration by Euphydryas phaeton butterflies." Phytochemistry 28(6): 1601-1604
- Nelson, G. PanFlora: Plant data for the eastern United States with emphasis on the Southeastern Coastal Plains, Florida, and the Florida Panhandle. www.gilnelson.com/PanFlora/ Accessed: 7 DEC 2016
- []Name That Plant. Accessed: April 1, 2016
- Robertson, K.M. Unpublished data collected from Pebble Hill Fire Plots, Pebble Hill Plantation, Thomasville, Georgia.
- []Native Florida Wildflowers. Accessed: April 1, 2016