Silphium asteriscus

Silphium asteriscus
Photo taken by Gil Nelson
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta – Flowering plants
Class:	Magnoliopsida – Dicotyledons
Order:	Asterales
Family:	Asteraceae ⁄ Compositae
Genus:	Silphium
Species:	S. asteriscus
Binomial name
Silphium asteriscus L.
Natural range of Silphium asteriscus from USDA NRCS NRCS Plants Database.

Common name: starry rosinweed

Description

A description of Silphium asteriscus is provided in The Flora of North America.

Ecology

Habitat

In the Coastal Plain in Florida and Georgia, S. asteriscus can be found in red oak/mockernut woods, sandy hillslopes, mixed hardwoods, upland pine forests, longleaf pine forests, annually burned pinelands, deciduous woods, upland oak-pine woodlands, pine flatwoods, calcareous outcrops, and longleaf pine-deciduous live oak flats (FSU Herbarium). In disturbed habitats it can be found in cutover upland longleaf pine savannas, along highways, along roads, and sandy fallow fields. Soil types include loamy sand, sandy loam and clay (FSU Herbarium). It has been observed to grow with Polymnia (FSU Herbarium). Associated species include shortleaf pine, post oak, red oak, mockernut hickory, longleaf pine, live oak, loblolly pine, and a Polymnia species (FSU Herbarium).

Outside of the Coastal Plain, it can be found in the Cross Timbers in wooded-open ecotones of oaks, ashes, elms, and hickories (Gee et al. 1994) and the Midland Plateau Central Highlands where the surface soil texture is sandy clay loam and clay subsoil (Miller, Boyd, Edwards 1999).

Phenology

S. asteriscus is a perennial species; stems have prickly hairs and can grow up to five feet high. The lower leaves are alternate and the upper are opposite and sessil. The flowers are yellow and have nine florets in the ray (Strong et al. 1848). Kevin Robertson has observed this species flower within three months of burning. KMR

Fire ecology

It resprouts and flowers within two months of burning in the spring (Robertson observation).

Use by animals

It is included in white-tailed deer diets in Cross Timbers ecosystem in Texas (Gee et al 1994).

In the Cross Timbers ecosystem of Texas, it has been found in white-tailed deer diets (Gee et al. 1994).

References and notes

• Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: July 2015. Collectors: Andre F. Clewell, Steve L. Orzell, Robert K. Godfrey, R. A. Norris, R. Komarek, Loran C. Anderson, Wilbur H Duncan, George R. Cooley, Richard J. Eaton, James D. Ray, Jr., R L Lazor, Gary R. Knight, C. Jackson, K. Craddock Burks, Richard S. Mitchell, A. H. Curtiss, R. Kral, Paul L. Redfearn, Jr. States and Counties: Florida: Bay, Dixie, Franklin, Gadsden, Jackson, Jefferson, Leon, Liberty, Levy, Okaloosa, Taylor, Wakulla. Georgia: Brooks, Grady, Hall, Thomas. Compiled by Tall Timbers Research Station and Land Conservancy.

• Gee, K. L. (1994). White-tailed deer : their foods and management in the cross timbers. Ardmore, OK, Samuel Roberts Noble Foundation.

• KMR

• Miller, J. H., R. S. Boyd, et al. (1999). "Floristic diversity, stand structure, and composition 11 years after herbicide site preparation." Canadian Journal of Forest Research 29: 1073-1083.

• Strong, A. B. (1848). The American flora, or history of plants and wildflowers: containing a systematic and general decription, natural history, chemical and medical properties of over six thousand plants, accompanied with a circumstantial detail of the medicinal effects, and of the diseases in which they have been most successfully employed. New York City, NY, Green & Spencer.