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Caulophyllum thalictroides

Common Name(s)
Blue cohosh
Flowering Time
Fruit/Seed Maturation Sign
Fruit turns blue
Fruit/Seed Collection Dates
Early September

Scarify seed (nick or cut a slit in seed coat); sow in fall outside or cold stratify in moist sphagnum until planting following spring; expect to see seedlings 2 years after planting (Mabry, in prep).

Of 330 seeds planted in a central Iowa demographic study, 83 (25%) germinated and 45 plants survivied to year 5; 18 flowered after an average of 10 years (Mabry in prep.).

Survivial of mature transplants added to a woodland degraded by cattle grazing in Wisconin declined over the eight years that they were monitored (Ellarson and Craven (1982).

Produces few seeds per plant with low vegetative spread (Barkely 1986, Gleason and Cronquist 1991).


Blue Cohosh (Caulophyllum thalictroides)

Seed Cleaning
None required
Intolerant of dry storage (Cullina 2000)
Restoration Potential
Medium to low by seed (requires patience)