[Beardtongues and Penstemons; The Genus Penstemon in the Cascade Mountains of Oregon and Washington]

Cascade Penstemon, Cascade Beardtongue, Coast Penstemon, Serrulate Penstemon

Penstemon serrulatus

Cascade penstemon as seen on open, talus slopes atop Castle Rock, Willamette National Forest........June 24, 2018.

Characteristics:

Cascade penstemon is an upright species of penstemon, with one to several slender stems rising from a woody base to 20 cm - 70 cm in height.

As with most penstemons, the leaves are opposite on the stems. The leaves of Cascade Penstemon are all found on the stems. They have short petioles at the bottom, while those above may be sessile or clasping. The lower leaves may be as long as 90 mm. The leaves may be almost entire to very serrate, lanceolate to elliptic or heart-shaped.

Cascade penstemon typically has a single, tight cluster of flowers at the tip of the flowering stem. However, there may be as many as five well-spaced verticillasters present. The sepals are narrow to ovate, with the margins very finely haired. The corolla is a short tube at the base of the flower which expands greatly to a longer, wider tube. The flowers are strongly two-lipped, to 25 mm long. The flower color is purple to blue.

Habitat:

Cascade penstemon inhabits moist woods and openings from sea level to about 6000 feet. Its habitat is one that is generally moister than that of most other penstemons.

Range:

Cascade penstemon is found in the west of the Cascade Mountain crest from southern Alaska through British Columbia and Washington to northwest Oregon.

- -

Cascade penstemon observed along the Boundary Trail #1 on Johnstone Ridge near the trail to Devil's Point, Mount Saint Helens National Volcanic Monument..........July 22, 2022.

Close-up of the inflorescence of cascade penstemon as seen along an old pack trail ascending steeply uphill from the uppermost portion of the South Fork Tieton River Trail #1120, Goat Rocks Wildernes........July 21, 2016.

A late blooming cascade penstemon observed along the Green River Trail #213, Gifford Pinchot National Forest (about one-half mile south of the Mt. St. Helens National Volcanic Monument.....September 4, 2019.

Paul Slichter