Vascular Plants of North Carolina
Account for Smooth Milkpea - Galactia volubilis   (L.) Britton
Members of Fabaceae:
Members of Galactia with account distribution info or public map:
Google Images
Section 6 » Order Fabales » Family Fabaceae
Show/Hide Synonym
Author(L.) Britton
DistributionThis species is what used to be called G. macreei, which in many older references and manuals was lumped into G. volubilis in the "old" and broad sense. G. volubilis in the "new" sense is restricted in NC to maritime and near-maritime situations, rarely further inland. Our map extends much too far inland and needs to be re-populated using Wilbur (1963) and RAB.

This is a mostly Coastal Plain species, ranging north to southeastern VA, and south to southern FL and west to eastern TX.
AbundanceCommon in the Sandhills region, and probably also frequent to common in most other parts of the Coastal Plain, with collections from nearly all counties. Scarce in the far northeastern counties.
HabitatThis is a species of dry to mesic sandy shrublands on dunes and interdunes, woodland borders, and sandy clearings.
PhenologyBlooms fairly early for a Galactia, from May to August, and fruits from July to October.
IdentificationThis is usually a strongly climbing vine that can reach 4-5 feet long. The stem has some hairs, and these may be backward slanting (retrorse) hairs, but it is not as villous/hairy as stems of G. regularis. The 3 leaflets of G. volubilis are somewhat differently shaped from those of G. regularis; they are ovate to lanceolate and about 1 inch long and notably narrower, but the widest part of the leaflet is just below the midpoint, toward the base. The leaflets of G. volubilis are somewhat thin in texture, as opposed to somewhat thick in the other. Also, Nesom (2015) notes that the undersides of the leaflets of this species are mostly glaucous (whitish). Lastly, G. volubilis has relatively large flowers; the rose to pink flowers are nearly 1/2-inch across (9-14 mm), as opposed to just 1/3-inch (7-10 mm) in G. regularis. Sorrie (2011) notes that in this species the standard (the large, top petal) is spread back such that the open flower is about "flat" (180 degrees); the flowers of G. regularis have the standard spread only about 90 degrees from the lower petals. Observers in the tidewater region will run into this milkpea often in their walks in drier habitats. Be careful of the identifications, as other species do occur there.
Taxonomic CommentsThe former G. macreei was considered as a part of this larger species by many references.

Other Common Name(s)Confusing. Nearly all references use, or better said, still use Downy Milkpea for the common name. However, this may have been for the taxon now named as G. regularis, which has downy stems. However, the editors feel that this common name is now "misapplied", to provide a word used for scientific taxa named incorrectly. Sorrie (2011) uses the names of Smooth Milkpea and Common Milkpea for this taxon. As the stem is relatively smooth, certainly as compared with G. regularis, this website uses Smooth Milkpea as the preferred (but not most prevalent) common name, in order to avoid confusion!
State RankS4 [S5?]
Global RankG5
State Status
US Status
USACE-agcpFACU link
USACE-empFACU link
County Map - click on a county to view source of record.
Select a source
AllHerbaria
Website
Select an occurrence type
AllCollection_natural