Bull. Torrey Bot. Club 27: 277. 1900.
Stems weakly erect to reclining, 10-30 cm, glabrous. Leaves basal and cauline; basal petioles 2 cm, distal petioles shorter. Leaf-blade: basal usually ternately compound, distal gradually less divided; leaflets nearly orbiculate to orbiculate-reniform, apically 4-7-lobed, 20-30 mm wide, lobe margins crenate, surfaces abaxially glaucescent. Inflorescences panicles, few flowered. Flowers: sepals white, spatulate to rhombic-spatulate, 1.5 mm; filaments white, 2-3 mm; anthers 0.3-0.5 mm. Achenes 3-8, spreading; stipe 2.5-3.5 mm, nearly as long as achene body; body flat, 2.5-4 mm, abaxial margin convex, adaxial margin straight, conspicuously 3-veined on each face; beak minute.
Phenology: Flowering late spring–early summer (Jun).
Habitat: Moist sandstone bluffs, sinks, and rocky crevices
Elevation: 200-1500 m
Ala., Ga., Ky., N.C., Tenn.
Of conservation concern.
Thalictrum mirabile is very similar to T. clavatum. Field studies are in progress to clarify the status of this species.