[Paintbrushes: The Genus Castilleja East of the Cascade Mountains of Oregon and Washington]

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush

Castilleja thompsonii

Synonym: Castilleja villicaulis

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush as seen high on the eastern slopes of Burch Mt., several miles north of Wenatchee, WA........June 6, 2009.

Characteristics:

Thompson's paintbrush is a perennial wildflower with clusters of ascending or erect, often branched stems rising10-40 cm high. The herbage consists of stiff, straight hairs or long, soft and shaggy hairs. The lowermost leaves are linear with entire margins while the leaves of the upper stem have 1-2 pairs of linear, spreading lobes.

The yellowish bracts are wider than the leaves and 3- to 5- parted. The calyx is often purplish, measuring 12-25 mm long, and is deeply but roughly equally parted above and below. The lateral calyx lobes are shallowly cleft into 2 triangular to linear lobes 1-3 mm long. The galea is often hidden within the calyx. The prominent lower lip is about 2/3-4/5 the length of the galea.

Habitat:

Thompson's paintbrush may be found in dry soils, often with sagebrush from the plains to near treeline along the eastern slopes of the Cascades.

Range:

Thompson's paintbrush may be found east of the Cascade Mts. from Southern British Columbia through Central Washington.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush as seen at left high on the eastern slopes of Burch Mt., several miles north of Wenatchee, WA........June 6, 2009. The photo at right shows Thompson's paintbrush in bloom along a jeep road north of Box Canyon Road, Simcoe Mountains Unit of the Klickitat Wildlife Area.....May 10, 2021.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush as seen at left near Rimrock Lake in Moses Coulee, central Washington........June 7, 2009. The photo at right shows Thompson's paintbrush on scablands about on-quarter mile uphill to the west of Wenas Campground, Yakima County, WA.......May 24, 2019.

Close-up of a flower and bracts of Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Close-up of the inflorescence of Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Close-up of the inflorescence of Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Additional close-up images of the inflorescences of Thompson's paintbrush as seen along the Colockum Pass Road, Wenatchee Mountains........July 7, 2012.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Additional examples of Thompson's paintbrush as seen growing beside big sagebrush and clumps of native bunchgrasses in scabland grasslands about one-half mile east of Odessa Craters, Lincoln County, Washington.........May 8, 2012.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush as seen growing in lithosol soils next to a small borrow pit along Road 35 about one-half mile uphill from the southern forest boundary on Table Mountain, Wenatchee National Forest.........June 4, 2013.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush seen with some of its host plants (Erigeron linearis at left, Trifolium macrocephalum at right) along What Road near the DNR-Wenatchee National Forest boundary north of Cleman Mountain, Yakima County, WA......May 24, 2019.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis) - Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush blooming atop Bickleton Ridge, Bickleton Ridge Unit of the Klickitat Wildlife Area.........June 17, 2017.

Thompson's Owl Clover, Thompson's Indian Paintbrush, Thompson's Paintbrush: Castilleja thompsonii (Synonym: Castilleja villicaulis)

Thompson's paintbrush as seen from sagebrush dotted ridgetop approximately 12 south-southwest of Toppenish, WA........early May, 1997.

Paul Slichter