[The Larkspurs of the Columbia River Gorge]

Columbian Larkspur, Cow Poison, Cow-poison, Poison Larkspur

Delphinium trolliifolium

Flowers of Cow Poison, Cow-poison, Poison Larkspur: Delphinium trolliifolium

Poison larkspur at Crown Point in the western Columbia River Gorge.....mid May, 2001.

Stem leaf of Cow Poison, Cow-poison, Poison Larkspur: Delphinium trolliifolium The photo at right shows a close-up of a stem leaf of poison larkspur as seen at MP 31 along the Columbia Gorge Highway to the west of Multnomah Falls.......................April 20, 2006.
Characteristics:

Poison larkspur is an attractive perennial wildflower with one to several stout and erect stems arising as much as 70-150 cm high. The stems are hollow and unbranched below the inflorescence. The herbage ranges from slightly hairy to smooth. There are numerous leaves on the stems and these become reduced in size upwards on the stem. The lower leaves range from 10-20 cm wide and are 3-lobed nearly to their base (See photo at right.). Each of the lobes are in turn further divided deeply into 2-3 segments.

The inflorescence is a simple to branched raceme of loosely arranged flowers. The inflorescence often is covered with fine, spreading, yellowish and often glandular hairs. The inflorescence is also noticeably leafy-bracteate below. The pedicels usually are longer than the calyx spur and somewhat spreading and ascending. The sepals are deep blue, each being oblong-lanceolate in shape with pointed tips. They measure 18-25 mm long. The spur is straight and occasionally somewhat arched downwards at the tip. The upper petals are whitish while the lower petals are bluish.


Habitat:

Poison larkspur may be found in moist shady woods and along shaded streambanks.


Range:

Poison larkspur is found from the Columbia River Gorge of Washington and Oregon south along the west side of the Cascade Mts. to Humboldt County, California.

In the Columbia River Gorge it may be found between the elevations of 100'-2000' between the Sandy River and McCord Creek.


Flower of Cow Poison, Cow-poison, Poison Larkspur: Delphinium trolliifolium

A close-up of a flower of poison larkspur. The large flaring bluish structures that look like petals at the center of the photo are actually the sepals. The smaller blue or white petals are located at the left edge of the flower in this photo.

Inflorescence of Cow Poison, Cow-poison, Poison Larkspur: Delphinium trolliifolium

A close-up of the inflorescence of poison larkspur as seen along the Angels Rest Trail in the Columbia River Gorge..................May 18, 2009.

Cow Poison, Cow-poison, Poison Larkspur: Delphinium trolliifolium

The lower stem leaves of poison larkspur as seen along the Angel's Rest Trail, Columbia River Gorge................February 9, 2010.

Paul Slichter