Actaea

Linnaeus

Sp. Pl. 1: 504. 175.

,

Gen. Pl. ed. 5, 222. 1754.

Common names: Baneberry necklaceweed cohosh actée
Etymology: Greek, aktea, ancient name for the elder, probably for leaf similarity
Treatment appears in FNA Volume 3.

Herbs, perennial, from caudices ca. 1 cm thick. Leaves cauline, alternate, petiolate. Leaf-blade 1-3-ternately or pinnately compound; leaflets ovate to narrowly elliptic, unlobed to 3-lobed, margins sharply cleft, irregularly dentate. Inflorescences terminal or axillary, 25 (-more) -flowered racemes, 2-17 cm; bracts leaflike, sometimes present between leaves and inflorescence, bracteoles 1-2, at base of each pedicel, not forming involucre. Flowers bisexual, radially symmetric; sepals not persistent in fruit, 3-5, whitish green, plane, orbiculate, 2-4.5 mm; petals 4-10, distinct, cream colored, plane, spatulate to obovate, clawed, 2-4.5 mm; nectary absent; stamens 15-50; filaments filiform; staminodes absent between stamens and pistils; pistil 1, simple; ovules many per pistil; style very short or absent. Fruits berries, solitary, sessile, broadly ellipsoid to nearly globose, sides smooth; beak a wart, terminal, to 1 mm. Seeds dark-brown to reddish-brown, obconic to wedge-shaped, rugulose. x = 8.

Distribution

Temperate to cool forests throughout Northern Hemisphere

Discussion

Species ca. 8 (2 in the flora).

The two species in North America are similar to each other vegetatively and differ primarily in flower and fruit characteristics.

Selected References

None.

Key

1 Pedicel in fruit bright red, stout, (0.7–)0.9–2.2(–3) mm diam., ± as thick as axis of raceme; stigma at anthesis as broad as or broader than ovary, 1.5–2.8 mm diam. in flower and fruit; petals truncate or cleft, often antherlike at apex; berries white, very rarely red. Actaea pachypoda
1 Pedicel in fruit dull green or brown, slender, 0.3–0.7 mm diam., thinner than axis of raceme; stigma at anthesis narrower than ovary, 0.7–1.2 mm diam. in flower and fruit; petals acute or obtuse, not cleft or antherlike at apex; berries red or white. Actaea rubra
... more about "Actaea"
Bruce A. Ford +
Linnaeus +
cuneate +, truncate +  and cordate +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
globose;cylindric +
Baneberry +, necklaceweed +, cohosh +  and actée +
Temperate to cool forests throughout Northern Hemisphere +
Greek, aktea, ancient name for the elder, probably for leaf similarity +
sessile +  and pedicellate +
showy +  and inconspicuous +
broadly ellipsoid;nearly globose +
axillary +  and terminal +
ovate +  and narrowly elliptic unlobed +
palmate +  and pinnate +
dentate +  and cleft +
incised;toothed;incised;toothed;entire +
distinct +
conspicuous +
Clawed (?) +, Spatulate (?) +  and Obovate (?) +
reduced +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
Sp. Pl. +  and Gen. Pl. ed. +
2 cm20 mm <br />0.02 m <br /> (17 cm170 mm <br />0.17 m <br />) +
not arillate +  and stalked +
rugulose +
obconic +  and wedge-shaped +
whitish green +
not persistent +
distinct +
3 +  and 6 +
orbiculate +  and plane +
0.2 cm2 mm <br />0.002 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
persistent +
Ranunculaceae +
0 cm0 mm <br />0 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
herbaceous +  and woody +