|Jeffersonia subsp. var.|
Jeffersonia which is also known as Twinleaf or Rheumatism root, is a small genus of herbaceous perennial plants in the family Berberidaceae. The two species are native to eastern Asia and eastern North America. They are uncommon spring wildflowers, which grow in limestone soils of rich woodland. Jeffersonia was named for United States President Thomas Jefferson, by his contemporary Benjamin Smith Barton. This genus was formerly, incorrectly grouped in genus Podophyllum. Twinleaf is protected by state laws as a threatened or endangered plant in Georgia, Iowa, New York, and New Jersey.
The leaves and flowers of this plant are smooth and emerge directly from the base of the plant. Jeffersonia has showy white flowers with eight petals; the flower resembles Bloodroot, a small poppy. The flower last only a short time after blooming in April or May, and gives way to a green pear-shaped capsule with a hinged top. The characteristic leaves are large and nearly divided in half, giving rise to its common name, Twinleaf. Plants in this genus rarely grow taller than 12 inches (30 cm).
|Standard Cyclopedia of Horticulture|
Jeffersonia (Thomas Jefferson, third president of the United States). Berberidaceae. Attractive hardy perennial herbs.
Rhizomatous: lvs. radical, palmately nerved, 2-lobed or 2-parted: fl. solitary on a naked scape; sepals 4, petaloid but fugacious; petals 8, flat, larger than sepals; stamens 8, free, with slender filaments; ovary single, the style 2-lobed at apex: fr. a caps., partially circumscissile near summit.—Two species, 1 in E. N. Amer. and 1 in Manchuria. The oriental species, J. dubia. Benth. & Hook., seems not to be in cult.
Pests and diseases
- Jeffersonia diphylla. Eastern North America.
- Jeffersonia dubia. Manchuria, China.
- Standard Cyclopedia of Horticulture, by L. H. Bailey, MacMillan Co., 1963