Bush Penstemon, Shrubby Penstemon: Penstemon fruticosus var. fruticosus (Synonym: Penstemon fruticosus ssp. fruticosus)

The photo above shows shrubby penstemon. The photos on this page were taken on the east-facing slopes of Crofton Butte at about 5070' on the south side of Mt. Adams..............June 19, 2005.

The photo above shows a close-up of the front of the flower of shrubby penstemon. Note the upper 2 corolla lobes that are reflexed upwards and the 3 lower lobes which are reflexed downwards as well as the hairy palate or throat of the lower lip and the long staminode that extends beyond the entrance to the throat of the flower.

Shrubby Penstemon is a woody, mat forming penstemon with numerous flowering and sterile stems atop dense mats of leaves. The flowering stems may reach a height of 40 cm and are freely branched.

The leaves are evergreen, leathery, and shiny green. The leaves are both basal and cauline (stem), with the latter being smaller. In variety fruticosus, the leaves are up to 6 cm long with entire or finely toothed margins.

The inflorescence is a few-flowered raceme. The glandular sepals are pointed at the tip. The corolla is blue-lavender to purple, and up to 5 cm in length. The palate is bearded and white or yellowish in color. The flowers are tubular with two spreading lips. The lower lip is longer than the upper. The calyx is glandular with entire-margined, leafy sepals from 7-15 mm long. The anther sacs are densely white and woolly. The staminode is yellow-bearded at the narrow tip and about one-half the length of the filaments.

Variety fruticosus: Leaf blades up to 6 cm long, usually 2-7 times longer than wide. Plants found from southern British Columbia south to the east of the Cascades in central Washington to the Columbia River Gorge and east across central Idaho to Montana, and Wyoming.

Variety scouleri: Leaf blades 2-5 cm long with mostly entire margins. Leaves linear in shape, mostly 6-10 times longer than wide. Plants of southeastern British Columbia, northeastern Washington, and northern Idaho.

Variety serratus: Leaf blades mostly 1-2.5 cm long with sharply toothed margins. Plants of southeastern Washington, northeastern Oregon and west-central Idaho.

Shrubby Penstemon inhabits rocky, often talus slopes to forests, from the foothills into alpine areas.

Shrubby Penstemon is found east of the Cascade summit from British Columbia, south through the Washington Cascades, and eastward to the Idaho panhandle, and again eastward to Wyoming. A southern branch extends through central Oregon to the Cascades, and also down the Columbia Gorge.

The photo at left shows a close-up side view of the corolla and calyx of shrubby penstemon. Note the glandular calyx but glabrous corolla as well as the tufts of hair in the throat of the corolla. The photo at right shows a second close-up side view of the corolla and calyx of shrubby penstemon. Note the glandular calyx but glabrous corolla as well as the tufts of hair in the throat of the corolla.

The photo above shows the internal floral structures of shrubby penstemon with the upper part of the corolla tube removed. The long arched structure is the stigma and style (part of the pistil or female part of the flower). Node that the 4 fertile stamens are densely covered with white, woolly hairs. The staminode, which is about half the length of the filaments (of the stamens) is yellow-bearded at its tip. It has been removed as it is attached towards the base of the upper corolla tube.

The photo above shows a close-up of the woolly stamens of shrubby penstemon. Visible in this photo are the anther sacs, which split fully along their length and spread fully open as they mature.

The photo above shows a lower leaf of shrubby penstemon. The leaves of this penstemon are largely entire or only slightly toothed. The similar Cardwell's penstemon has leaf margins that are serrulate and leaf tips that are rounded or obtuse.

The photo above shows an albino form of shrubby penstemon as seen on the north side of Mt. Adams........July 12, 2005.

Shrubby penstemon growing at left on the Ridge of Wonders, Tract D Yakama Nation lands at the southeastern corner of Mt. Adams.........August 13, 2012. The image at right shows shrubby penstemon blooming along the Shorthorn Trail #16, Mount Adams Wilderness.....July 22, 2024.

Shrubby penstemons observed on rock outcrops along the middle section of the Shorthorn Trail #12, Mt. Adams Wilderness......July 10, 2020.

Shrubby penstemons along the Buck Creek Trail #54 blooming on rock outcrops on the north rim of the White Salmon River canyon, Mount Adams, Gifford Pinchot National Forest.......May 29, 2020.

Shrubby penstemons seen along the Climber's Trail on the south rim of Hellroaring Valley, Yakama Nation lands at Bird Creek Meadows.....July 26, 2023.