Aconitum columbianum subspecies columbianum (Monkshood)
Ranunculaceae  (Buttercup Family)

Subalpine. Woodlands, meadows, wetlands.  Summer.
Above: Rough Canyon Trail, July 17, 2023 and Kilpacker Trail, August 19, 2019.
Left: Pass Creek Trail, August 2, 2005; Kilpacker Trail, July 10, 2012; and Rough Canyon Trail, July 18, 2016.

The top photo at left shows a typical setting for Aconitum columbianum, buried in other plants that also enjoy having wet roots.  The Corn-like leaves are those of Veratrum californicum, and the yellow Sunflower is Senecio triangularis. All three enjoy moist, even wetland soils, as also shown in the photograph at the top of the page.

The second photo shows a surprising characteristic of the Aconitum flower: The showy purple floral parts are not petals; they are sepals. Two petals are short and tubular with split lower lips and coiled spurs. They are concealed within the upper hooded sepal and can be seen just barely protruding and curling under the hood.

Aconitum columbianum subspecies columbianum (Monkshood)
Ranunculaceae  (Buttercup Family)

Subalpine.  Woodlands, meadows, wetlands.  Summer.
Upper Calico Trail, July 21, 2005.

Monkshood often is mistaken for its cousin Delphinium barbeyi; the two grow in similar moist habitats and both have broad, leafy, sometimes shrub-like growth, and very tall flower stalks.  Delphinium, though, reaches seven feet tall and Monkshood only five.  Monkshood flowers are most often intensely deep purple with a high arching hood.  Delphinium flowers range from inky blue through violet to purple and have a distinctive spur. 

Delphinium is far more common but a discerning eye will often find Monkshood growing with Delphinium. The pictured plants are just over two feet tall and will grow another foot or two.

Where you find one A. columbianum plant, you will almost always find several more of them since they reproduce both by seed and vegetatively, sprouting a tuber from the root crown. The tuber gives rise to another plant and can also send out a rhizome which produces another tuber and another plant.  

Notice the characteristic deeply incised leaves of Monkshood. 

Linnaeus named this genus in 1753 from a European specimen. The genus is circumboreal with about 100 species worldwide. Eurasia is the center of diversity. There are perhaps six native North American Aconitum taxa with A. columbianum being by far the most widely distributed, as the map below indicates. A. columbianum was first collected for science by famed botanist Thomas Nuttall near the Columbia River around Walla Walla in 1834. 

"Aconitum" is most often said to be derived from the Greek for "pointed stone" (which would have been tipped with a poisonous extract form the plant), but the Flora of North America indicates, "according to Pliny, the name "aconite" is taken from the ancient Black Sea port Aconis".

"name and probably means "unconquerable poison", referring to the plant's toxicity.  "Columbianum" refers to the plant's American (Columbian) location.

Aconitum columbianum subspecies columbianum (Monkshood)
Ranunculaceae  (Buttercup Family)

Subalpine.  Woodlands, meadows, wetlands.  Summer.
Sharkstooth Trail, July 30, 2004.

Aconitum columbianum subspecies columbianum (Monkshood)
Ranunculaceae  (Buttercup Family)

Subalpine.  Woodlands, meadows, wetlands. Summer.
Near Roaring Fork Road, August 5, 2020.

Leaves of these five species are quite similar.

Range map © John Kartesz,
Floristic Synthesis of North America

State Color Key

Species present in state and native
Species present in state and exotic
Species not present in state

County Color Key

Species present and not rare
Species present and rare
Species extirpated (historic)
Species extinct
Species noxious
Species exotic and present
Native species, but adventive in state
Eradicated
Questionable presence

Range map for Aconitum columbianum