Galactia volubilis

Galactia volubilis
Photo by John R. Gwaltney, Southeastern Flora.com
Scientific classification
Kingdom:	Plantae
Division:	Magnoliophyta - Flowering plants
Class:	Magnoliopsida – Dicotyledons
Order:	Fabales
Family:	Fabaceae ⁄ Leguminosae
Genus:	Galactia
Species:	G. volubilis
Binomial name
Galactia volubilis (L.) Britton
Natural range of Galactia volubilis from USDA NRCS Plants Database.

Common name: downy milkpea

Description

This species is a climbing vine with twining behavior (FSU Herbarium).

Generally, the genus Galactia are "trailing or twining, climbing, perennial, herbaceous or woody vines or erect, perennial herbs or rarely shrubs. Leaves 1-pinnate, usually 3-foliolate (or rarely 1-,5-7-,9-folilolate); leaflets entire, petiolulate, stipellate. Racemes axillary, pedunculate with few to numerous, papilionaceous flowers borne solitary or 2-several at a node, ech subtended by a bract and fusion of the 2 uppermost, with the laterals usually shorter than the uppermost and lowermost; petals usually red, purple, pink or white; stamens diadelphous or elsewhere occasionally monadelphous; ovary sessile or shortly stipitate. Legume oblong-linear to linear, few-many seeded, compressed, straight or slightly curbed, dehiscent with often laterally twisting valves."- Radford et al 1964

Specifically, for this species, G. volubilis, they are "twining, climbing, herbaceous vines with sparsely to densely, spreading pubescent stems, 1-1.5 m long. Leaves 3-foliolate, rachis 2-18 mm long; leaflets narrowly to widely oblong, oblong-ovate or elliptic, (1) 2-4 (6) cm long, glabrous, or nearly so, above and glabrate to more commonly appressed short-pubescent to spreading pilose beneath. Racemes with peduncles and rachises sparsely to densely spreading short-pubescent, 3-15 (30) cm long; flowers 1-3 at each node on spreading short-pubescent pedicles 1-4 mm long subtended by triangular bracts 0.4-1.2 mm long; bractlets triangular, 0.4-1 mm long. Calyx spreading short-pubescent, tube 2-2.5 mm long, lobes 2-3.5 mm long; petals pink to roseate, the standard 7-10 mm long. Legume 2-5.5 cm long, 4-5 mm broad, densely spreading short-pubescent." - Radford et al 1964

Distribution

“…occurring in sandy soils from New York to Florida westward to Tennessee and Texas.”

Ecology

Habitat

This species is found in mixed hardwood forests, pinewoods, shrub and herb dominated communities, old fields, ravine dissected areas, dry pocosins, flatwoods, creek banks and savannahs (FSU Herbarium). It has been observed to grow in dry and moist sandy loam in open areas with full sunlight (FSU Herbarium). G. volubilis has also been seen growing in areas disturbed by humans such as bulldozed scrub sandhills, along roadsides, cleared sites, and clear cut longleaf pine-scrub habitats (FSU Herbarium). Associated species include Desmodium ochrolecum, D. rotundifolium, Rhus aromatica, Centrosema species, Paspalum species, Fagus species, Carya tomentosa, Pinus palustris, Pinus elliottii, Quercus laurifolia, Quercus virginiana, Quercus laevis, Sabal palmetto, Magnolia ashei, Aristida stricta. Galactia regularis, Rhynchosia difformis, Setaria, Phlox, and Cuphea. Also includes Broomsage and Silver palm (FSU Herbarium).

Phenology

“A lavender-flowered prostrate perennial herb frequently climbing over bushes...It is variable species and varietal forms have been described” This species has been observed to flower from May through September and November and fruiting from May to November (FSU Herbarium).

Fire ecology

The amount of G. volubilis decreased after a spring burn, summer burn, and in the control plot “Results from previous studies indicate that leguminous plants and seed respond best to “hot” fires such as those in which a high proportion of the ground fuel is consumed. Laboratory tests have also shown that seed from several leguminous species germinate best after scarification with moist heat at temperatures near 80 degrees C., a situation requiring a hot fire. The response of the leguminous plants and seed in this study, therefore, would probably have been greater if the pine stands had been burned with more intense fires. ” G. volubilis had the greatest coverage on the plots burned in January at the loblolly-shortleaf pine communities of the Alabama upper coastal plain. This species has also been found in areas that were excluded from fire (FSU Herbarium).

Use by animals

Eastern mourning dove includes G. volubilis in its diet.

References and notes

Florida State University Robert K. Godfrey Herbarium database. URL: http://herbarium.bio.fsu.edu. Last accessed: June 2014. Collectors: Loran C. Anderson, Gary R. Knight, Richard S. Mitchell, R.K. Godfrey, L. M. Baltzell, O. Lakela, J. Ferborgh, Jane Brockmann, R. W. Long, L. J. Brass, H. A. Lang, C. Jackson, A. F. Clewell, R. C. Phillips, R. Kral, M. Davis, Richard R. Clinebell II, R. L. Wilbur, W. B. Fox, R. Komarek, J.M. Kane, Chris Cooksey, Kevin Oakes, Charles S. Wallis, John B. Nelson, and D.E. Kennemore. States and Counties: Florida: Citrus, Dade, Duval, Escambia, Gulf, Franklin, Hardee, Hernando, Hillsborough, Jackson, Jefferson, Leon, Levy, Monroe, St. Lucie, Taylor, and Wakulla. Georgia: Grady, McIntosh, and Thomas. North Carolina: Craven and Cumberland. Oklahoma: Latimer. South Carolina: Orangeburg and Richland.

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. 643-4. Print.