Black Cohosh

Merrill and his Cohosh

During a tour of the Dubach's land deep in Swan Creek territory, we stopped to see a patch of Black Cohosh, its flowers almost through for the year.  It would have been easy to miss them as we drove by.

Black Cohosh (Actaea racemosa).  previously called Cimicifuga racemosa is also called bugbane because of its insect repelling odor.  It tends to grow in richer soil in shaded areas, and is partial to small openings in the woods like Merrill's.

Cohosh flowers in the late spring to early summer with blooms atop tall spiked stems.  The flowers have no petals or sepals, just small white stamens surrounding a white stigma.  They do not attract butterflies in general, relying instead on their sweet fetid odor which attracts flies, gnats, and beetles to spread their pollen.

Tripinnate leaf- all one leaf

The large basal tripinnate leaves are interesting.  Tripinnate means "divided into pinnae that are subdivided into smaller, further subdivided leaflets or lobes." The picture shows a single leaf, divided into three leaflets which are again divided into subleaflets.  This one pinnate leaf can measure 3 feet long and wide are made up of three coarsely tooth pinnate leaflets.

In other words, what you see in this picture is all one big leaf.

Native Americans used the ground roots and rhizomes for the treatment of pain and inflammation.  Nineteenth century eclectic physicians used it for a wide variety of disorders.  Now there are serious studies in progress on its use in treating menopausal hot flashes, described in this NIH Fact Sheet.

Merrill's patch probably won't ever bring him out of retirement for a fourth time, although with his Master Gardener training, you never know what he will do next.  For now the Cohosh provide a pretty sight in the understory of his woods.

Good pictures and descriptions at missouriplants.com,
and facts are at Wikipedia.