Stylosanthes biflora

Stylosanthes biflora
Photo taken by Michelle M. Smith
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta – Flowering plants
Class:	Magnoliopsida – Dicotyledons
Order:	Fabales
Family:	Fabaceae ⁄ Leguminosae
Genus:	Stylosanthes
Species:	S. biflora
Binomial name
Stylosanthes biflora (L.) Britton, Sterns & Poggenb.
Natural range of Stylosanthes biflora from USDA NRCS Plants Database.

Common name: sidebeak pencilflower

Description

"Prostrate to erect, perennial herb, stems few to many, 1-5 dm long, glabrate to bristly-hirsute. Leaves pinnately 3-foliolate; leaflets elliptic to oblanceolate, 1.5-4 cm long, entire, estipellate; stipules striate, finely pubescent to bristly hirsute, subulate, (0.4) 1-1.5 cm long, aristately tipped. Hypanthium pedicel-like, glabrous, 3-4 mm long. Calyx glabrous, tube short, campanulate above the filiform hypanthium, upper 2 lobes united, obtuse, 1.2-1.8 mm long, the 2 lateral lobes oblong, obtuse, ca. 1 mm long, the lowermost lobe acute, ca. 2 mm long; petals orange-yellow to whitish, standard 5-9 mm long; stamens 10, monadelphous, anthers alternating between oblong and subglobose. Legume short-pubescent, obliquely ovate, 3-5 mm long, sessile, reticulate, usually only the upper segment maturing, the lower pedicel-like." - Radford et al 1964

Ecology

It is a legume (Hiers et al 2000).

Habitat

Occurs in frequently burned pinelands such as longleaf pine and scrub oak ridges (FSU Herbarium). Also occurs in pine, oak, hickory woods (FSU Herbarium). Also occurs in human disturbed areas such as roadsides and right-of-ways, in clearings, fallow fields, and in pastures (FSU Herbarium). Associated species include Phlox floridana, Stillingia sylvatica, Asimina longiflolia var. spathulata, Lactuca graminifolia, Stylosanthes biflora, Erigeron strigosa, Baptisia lanceloata, Hedyotis crassifolia, Tercauloon undulatum, Asclepias humistrata, Quercus hemisphaerica, Pinus palustris, Panicum, Andropogon (FSU Herbarium).

It can live in xeric areas (Carter et al 2004). It can survive in disturbed areas (Kirkman et al 2004). In Baker County, Georgia at Jones Ecological Research Center with native groundcover managed with frequent fire (Birkhead et al 2005; Simkin et al 2001). It is common in longleaf pine communities (Carter et al 2004). Hainds and his team found that S. biflora occurred in 92.3% of the plots (Hainds et al 1999). Longleaf pine flatwoods that are mesic, fire-maintained savannas or sparse woodlands with nutrient-poor soils (Brewer and Cralle 2003). Longleaf pine stands that originated from seed in Rapides Parish, Louisiana that have fine sandy loam soils (Haywood et al 1998). In Buettner Xeric Limestone Prairies in Monroe County, Illinois they have outcrops along streams and river where a prescribed burn was conducted in the nearby woody area in 2010 (McClain and Ebinger 2014).

Phenology

Has observed flowering and fruiting from April to December (FSU Herbarium). It has a mid-summer flowering peak (Hiers et al 2000). Following a lightning-season burn, it continues to reproduce through late summer and fall (Hiers et al 2000).

Seed dispersal

According to Kay Kirkman, a plant ecologist, this species disperses by gravity.

Fire ecology

It seems to thrive under frequent burning around the summertime. Lightning-season burns seem to significantly increase flowering, but only after a dramatic delay (Hiers et al 2000). Density of S. biflora was greater after frequent late dormant-season fires (Sparks et al 1998). S. biflora was found only in annual winter and annual summer long-term (20 years) burned loblolly pine plots, and even then, only rarely (Lewis and Harshbarger 1976).

Use by animals

Gopher tortoises (Gopherus polyphemus) graze on Stlosanthes bioflora (Birkhead et al 2005).

References and notes

Birkhead, R. D., C. Guyer, et al. (2005). "Patterns of folivory and seed ingestion by gopher tortoises (Gopherus polyphemus) in a southeastern pine savanna." American Midland Naturalist 154: 143-151.

Brewer, J. S. and S. P. Cralle (2003). "Phosphorus addition reduces invasion of a longleaf pine savanna (southeastern USA) by a non-indigenous grass (Imperata cylindrica)." Plant Ecology 167: 237-245.

Carter, R. E., M. D. MacKenzie, et al. (2004). "Species composition of fire disturbed ecological land units in the Southern Loam Hills of south Alabama." Southeastern Naturalist 3: 297-308.

Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: August 2014. Collectors: Loran C. Anderson, Lisa Keppner, Ed Keppner, Nancy E. Jordan, Gary R. Knight, Robert K. Godfrey, F. S. Earle, C. F. Baker, S. W. Leonard, Gwen Roney, C. Jackson, Robert Kral, Mabel Kral, Gwynn W. Ramsey, Richard S. Mitchell, O. Lakela, D. B. Ward, L. J. Brass, Robert L. Lazor, Jean W. Wooten, S. C. Hood, R. C. Phillips, William Reese, Paul Redfearn, Leon Neel, R. Komarek, R. A. Norris, Andre F. Clewell, Chris Cooksey, M. Davis, Cecil R Slaughter, Peter H. Raven, Tamra Engelhorn Raven, C. L. Huff, C. Ritchie Bell, James W. Hardin, Wilbur H Duncan, Effie Boon, M. Morgan, R. L. Wilbur, H. K. Svenson, A. B. Seymour, D. S. Correll, H. B. Correll, H. R. Reed, Delzie Demaree, I. M. Johnston, G. Edwin, L. J. Uttal, Norlan C. Henderson, L. B. Smith, A. R. Hodgdon, M. A, Chrysler, S. J. Ewer, Roy Hood, R. D. Houk, Kurtz, Angus Gholson, Jr., David M. DuMond, Clarke Hudson, John W. Thieret, S. B. Jones, Bob Mills, Champ Clark, Sidney McDaniel, Samuel B. Jones, Jr., James G. Teer, Roomie Wilson, P. L. R., Elizabeth Ann Bartholomew, Edward S. Steele, Duane Isely, A. J. Sharp, S.M. Tracy, F. H. Sargent, W. W. Ashe, David Moreland, John R. Wood. States and Counties: Alabama: Clarke, Covington, Cullman, Escambia, Henry, Lee. Arkansas: Columbia, Hot Spring, Logan, Pulaski, Saline. Florida: Bay, Citrus, Duval, Escambia, Flagler, Franklin, Gadsden, Gulf, Hillsborough, Jackson, Jefferson, Lafayette, Leon, Liberty, Okaloosa, Putnam, Suwannee, Taylor, Wakulla, Walton, Washington. Georgia: Decatur, Grady, Johnson, Mitchell, Rabun, Seminole, Taylor, Thomas, Toombs. Illinois: Lawrence. Kansas: Montgomery. Louisiana: Bienville, Claiborne, Natchitoches, Tangipahoa. Mississippi: Amite, Covington, Harrison, Jackson, Jones, Lamar, Marion, Panola. Missouri: Benton, Carter, Dallas, Dent, Jefferson, McDonald, Ozark, Polk, St Clair. New Jersey: Atlantic. North Carolina: Burke, Catawba, Craven, Guilford, Iredell, Lee, Warren. South Carolina: Oconee, Union. Tennessee: Bledsoe, Coffee. Texas: Brazos, Harris, Morris, Shelby, Walker. Virginia: Dinwiddie, Greensville, Henry, Montgomery, Prince William, Roanoke, Rockingham. West Virginia: Wirt.

Hainds, M. J., R. J. Mitchell, et al. (1999). "Distribution of native legumes (Leguminoseae) in frequently burned longleaf pine (Pinaceae)-wiregrass (Poaceae) ecosystems." American Journal of Botany 86: 1606-1614.

Haywood, J. D., A. Marti, et al. (1998). Seasonal biennial burning and woody plant control influence native vegetation in loblolly pine stands. Research Paper SRS-14. Asheville, NC, USDA Forest Service.

Hiers, J. K., R. Wyatt, et al. (2000). "The effects of fire regime on legume reproduction in longleaf pine savannas: is a season selective?" Oecologia 125: 521-530.

Kirkman, L. K., K. L. Coffey, et al. (2004). "Ground cover recovery patterns and life-history traits: implications for restoration obstacles and opportunities in a species-rich savanna." Journal of Ecology 92: 409-421.

Lewis, C. E. and T. J. Harshbarger (1976). "Shrub and herbaceous vegetation after 20 years of prescribed burning in the South Carolina coastal plain." Journal of Range Management 29: 13-18.

McClain, W. E. and J. E. Ebinger (2014). "Vascular Flora of Buettner Xeric Limestone Prairies, Monroe County, Illinois." Southern Appalachian Botanical Society.

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. 604. Print.

Simkin, S., W. Michener, et al. (2001). "Plant Response Following Soil Disturbance in a Longleaf Pine Ecosystem." Journal of the Torrey Botanical Society 128(3): 208-218.

Sparks, J. C., R. E. Masters, et al. (1998). "Effects of late growing-season and late dormant-season prescribed fire on herbaceous vegetation in restored pine-grassland communities." Journal of Vegetation Science 9: 133-142.