Actaea racemosa

Actaea racemosa black cohosh

Plant grows in the wild/spontaneouslyPlant is native to PA Synonyms:   Cimicifuga racemosa
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This stately herbaceous perennial is most notable for its long, drooping branches adorned with numerous tiny white flowers and a distinct pungent smell. Each plant produces one or more flower panicles, each containing 4 to 9 racemes that range from 4 to 24 inches in length. There is a central larger raceme surrounded by several secondary racemes. The racemes can be covered with buds, fruits, and flowers in various stages of development. The leaves are quite large and compound, twice pinnate or thrice pinnate with irregularly shaped leaflets.

Black cohosh is a relatively common plant that can grow up to 8 feet tall, especially in shady, pH-neutral soils.  This plant prefers rich soil with plenty of organic material and thrives in partial sun to medium shade. It is found in all counties of the state except Wayne, Sullivan, and Susquehanna. It predominantly grows in rich mesic woods, along forest edges, or in ravines.

Black cohosh is primarily pollinated by bees, such as bumblebees and other native bee species. The plant's flowers produce abundant nectar and pollen to attract bees, beetles and flies.

Common in rich moist woods, wooded slopes, edged of dense wood and gallies. Prefers partial sun to medium shade.

Present throughout the state excluding Wayne, Sullivan and Susquehanna counties.

Range: Ontario south to Georgia and Tenessee; Massachusets west to Missouri

Wetland code: Not classified

Flowers June to early August.  Blooming period is about 6 weeks.

Inflorescence  monoecious; panicle with 4 to 9 racemes 4 to 24″ long

 Flowers  radially symmetric, perfect, numberous; on short pedicel; 24 long, slender stamens, 1 pistil, 4 sepals;  ⅔″ across

Leaves  large, pinnately compound, petiolate; normally bipinnate or tripinnate with 10 or more leaflets

  Leaflets  glabrous, irregular, medium green; margins dentate to deeply serrate; up to 4″ long; terminal leaflets ovate to obovate

Stems  solitary; hairy to smooth; light green

Fruit  ovoid hairy follicle with short, curved beak; ⅓″ long; 8 to 10 seeds in two rows

Height  3-8 feet

S-rank:  G5 (Secure)
G-rank:  G3 (Vulnerable)

Traditionally, black cohosh has been primarily used as a sedative, relaxant, and antispasmodic. Some Native American tribes utilized a brew made from its rhizome to alleviate menstrual and childbirth pain, and applied a rhizome poultice to treat snakebites.

Bumbleebees and other native bees pollinate the flowers and other insects such as flies and beetles come for pollen and nectar.  Black cohosh is the only host plant for Appalchian Azure butterfly.  

Mammals very rarely feed on this plant because of its fetid odor and toxicity.

Actaea racemosa black cohosh

Plant grows in the wild/spontaneouslyPlant is native to PA
Synonyms:   Cimicifuga racemosa
Actaea racemosa gallery
Plant Life-Form
perennial forb
Common Names