Loading profile. Please wait . . .
Polygala leptostachys Shuttlw. ex Gray
Georgia Milkwort
Federal Protection: No US federal protection
State Protection: No Georgia state protection
Global Rank: G3G4
State Rank: S1
Element Locations Tracked in Biotics: Yes
SWAP 2015 Species of Greatest Conservation Need (SGCN): No
SWAP 2025 Species of Greatest Conservation Need (SGCN): Yes
2025 SGCN Priority Tier: High Conservation Concern
Element Occurrences (EOs) in Georgia: 3
Habitat Summary for element in Georgia: Oak-pine scrub
Annual herb with smooth, erect stems 6 - 20 inches (15 - 50 cm) tall, sometimes branched. Leaves are 0.1 - 1 inch long, very narrow and needle-like (0.3 - 3.0 cm long and 0.5 - 2.5 mm wide), smooth, arranged in widely spaced whorls except near the flower cluster where they are alternate. The flower cluster is 0.2 - 2.4 inches tall (0.5 - 6 cm long and 0.2 - 0.4 cm wide), narrowly cylindric, and held erect at the top of the stem or ends of branches (if any). Flowers are very small (1.5 - 2.8 mm), white or greenish white, with two petal-like sepals (called “wings”), three smaller sepals, and three petals, one called a “keel” due to its boat shape that bears a two-lobed, fringed crest. Fruits are oblong capsules less than 0.1 inch (1.7 - 2.2 mm) long; the fruits ripen from the bottom up, with fruits being released from the bottom of the inflorescence while the upper inflorescence is still elongating and blooming.
Polygala balduinii var. balduinii (White Milkwort) is the only other white-flowered Polygala in Georgia’s Coastal Plain, where it is rare (see below). It has alternate leaves and a much-branched flower cluster bearing many flower heads.
Polygala balduinii var. balduinii (White Milkwort, Georgia Special Concern) occurs in Georgia’s Coastal Plain in moist depressions in open pine flatwoods and savannas.
Polygala chapmanii (Chapman's Milkwort, Georgia Special Concern) occurs on and around Altamaha Grit outcrops and in wet pine flatwoods in the Coastal Plain.
Polygala crenata (Crenate Milkwort, Georgia Special Concern) occurs in Bald Cypress-dominated floodplains in the Coastal Plain.
Polygala senega (Seneca Snakeroot, Georgia Special Concern) occurs in woodlands on steep slopes, especially over calcareous or mafic rocks, in north Georgia.
Sandhills, oak scrub, dry pine woodlands.
Polygala leptostachys is an annual herb that reproduces sexually by seed. As with other members of the genus, its flowers are bisexual and produce nectar, and have evolved to facilitate insect pollination. A lower petal, called a keel, attracts pollinators with a conspicuous crest divided into finger-like sections. The keel also serves as a lever – when an insect, usually a bee, lands on the crest, its weight opens the keel, exposing the stamens that are otherwise protected within. A few Polygala species have cleistogamous (closed) flowers, but not P. leptostachys. Flowers within a Polygala inflorescence open from the bottom up, with seeds maturing and dispersing from the bottom of the inflorescence while the upper portion is still elongating and blooming. Flowers at the bottom of such indeterminate inflorescences are more likely to produce fruits because they are closer to the source of nutrients. Since bees tend to forage from the bottom up, this flower-opening sequence increases the likelihood that lower flowers receive pollen from other plants and that they produce fruits with outcrossed seeds.
Surveys should be conducted during mid- to late summer (July–August) when the plants are in flower.
Georgia, Florida, Alabama, and Mississippi. It is rare throughout its range.
Sandhills, oak scrub and woodlands, and pine flatwoods are threatened by conversion to pine plantations, pastures, and residential and commercial development. Fire suppression. Invasion by Cogon Grass.
| Threat 1 | Threat 2 | Threat 3 | |
|---|---|---|---|
| General Threat | Residential & commercial development | Climate change & severe weather | None |
| Specific Threat | None | None | None |
Polygala leptostachys is ranked S1 by the Georgia Department of Natural Resources, indicating that it is critically imperiled in the state. Three populations have been documented in Georgia, none on conservation lands, and none have been confirmed in recent decades.
Protect sandhills, oak scrub and woodlands, and pine flatwoods from conversion and development. Apply prescribed fire every 2 - 3 years. Eradicate Cogon Grass.
Abbott, J.R. 20xx. Polygalaceae [in press]. Flora of North America, Vol. 10-11. Oxford University Press, New York.
GADNR. 2019. Element occurrence records for Polygala leptostachys. Georgia Department of Natural Resources, Wildlife Resources Division. Social Circle, Georgia.
NatureServe. 2020. Species account for Polygala leptostachys. NatureServe Explorer: an online encyclopedia of life. NatureServe, Arlington, Virginia. https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.136172 /Polygala_leptostachys
Weakley, A.S. 2015. Flora of the southern and mid-Atlantic States. University of North Carolina Herbarium, University of North Carolina, Chapel Hill. http://www.herbarium.unc.edu/flora.htm
Wyatt, R. 1982. Inflorescence architecture: how flower number, arrangement, and phenology affect pollination and fruit-set. American Journal of Botany 69 (4): 585-594.
Linda G. Chafin
Linda G. Chafin, 23 April 2020: original account.