[Horsebrush: The Genus Tetradymia East of the Cascade Mts. of Oregon and Washington]

Little-leaf Horsebrush

Tetradymia glabrata

Little-leaf horsebrush as seen along the Domingo Pass Road at the east side of the Pueblo Mountains of southeastern Oregon..........May 31, 2012.

The photo at right shows the leaves of little-leaf horsebrush as found at Mickey Hot Springs, BLM, SE Oregon.........June 24, 1999.

Characteristics:

Little-leaf horsebrush is a much-branched shrub from 30 to 80 cm tall. The twigs are often persistently white-tomentose in lines (note vertical white lines on twigs in photo at right) or occasionally glabrous. The primary leaves of young shoots are erect, rigid and sharp pointed and about 6-10 mm long.The primary leaves are soon deciduous. The secondary leaves are thinly linear, somewhat wider in the middle with rounded tips (see photo at right) and often closely ascending or appressed to the twig. The secondary leaves are about 10 mm in length and may be thinnly tomentose to green and glabrous.

The flower heads are in small cymes at the ends of the branches, with 4 flowers in each head. The involucre is 7-10 mm high and consists of 4 tomentose to glabrous bracts.

Habitat:

Little-leaf horsebrush is found in open dry places in the foothills and plains up to an elevation of 2000 meters.

Range:

Little-leaf horsebrush is found from Wasco and Wheeler Counties in central Oregon east to central Idaho, and south to Utah, Nevada and southern California.

Close-ups of the stems of little-leaf horsebrush as seen along the Domingo Pass Road at the east side of the Pueblo Mountains of southeastern Oregon..........May 31, 2012.

Little-leaf horsebrush as seen on east-facing slopes of the Hart Mt. ridgeline a mile or so west of Hot Springs Campground, Hart Mt. National Antelope Refuge..........June 9, 2016.

Seed heads of Little-leaf Horsebrush: Tetradymia glabrata

The photo above shows the seed heads of little-leaf horsebrush as found at Cottonwood Creek, Pueblo Mts south of Fields, OR..........June 28, 1999.

Little-leaf Horsebrush: Tetradymia glabrata

The photo above shows the inflorescence of little-leaf horsebrush as found at Mickey Hot Springs, BLM, SE Oregon.........June 24, 1999.

Little-leaf Horsebrush: Tetradymia glabrata

The photo above shows the inflorescence of little-leaf horsebrush as found at Mickey Hot Springs, BLM, SE Oregon.........June 24, 1999.

Paul Slichter