[Yampahs: The Genus Perideridia East of the Cascade Mountains of Oregon and Washington]

Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah

Perideridia gairdneri ssp. borealis

Synonyms: Atenia montana, Carum montanum, Perideridia montana

Umbel of Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah: Perideridia gairdneri ssp. borealis (Synonyms: Atenia montana, Carum montanum, Perideridia montana)

The photo above shows a top view of the flattened inflorescence of common yampah as seen at a dry creek along Road K1000 near the Klickitat-Yakima County line.........July 28, 2006.


Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah: Perideridia gairdneri ssp. borealis (Synonyms: Atenia montana, Carum montanum, Perideridia montana)The photo at right shows the upper leaves and several umbels of yampah as seen along the Chief Joseph Trail in the Eagle Cap Wilderness just west of Wallowa Lake........July 27, 1997. The photo clearly shows the multiple umbels on the same stem.
Characteristics:

Also known as western false caraway and squawroot, yampah is a glabrous perennial wildflower with a slender erect, sinuous stem from 30-100 cm high arising from a cluster of fleshy roots. The leaves are pinnately compound (or occasionally bipinnately compound) and measure from 10-20 cm long with wide petioles. The few, narrowly linear leaflets are 5-15 cm long (See photo above.). The several leaves are evenly spaced along the stems and are only slightly reduced in size upwards on the stem. The lower leaves often wither by the time of flowering.

The inflorescence consists of 3-10 umbels with 8-16 rays measuring up to 6 cm long. Typically, the umbels are each subtended by several awl-shaped bracts. The umbellets are each subtended by several narrow bractlets while the pedicels are 4-6 mm long. The flowers vary from white to pinkish in color and the petals usually have 5-7 evident veins from the base and are notched at the tip. The fruits are broadly oval and measure from 1-3.5 mm long and about as wide. The surface of the fruit is covered with minute ribs.


Habitat:

Yampah may be found on moist to dry, rocky hillsides, woodlands or in moist to dry meadows from the foothills to about 2500 meters of elevation in the mountains.


Range:

Yampah may be found from southern British Columbia south to the east of the Cascade Mts. to northern California and east to the Snake River Plain and Caribou Range of Idaho and northern Nevada and northern Utah. It is found further eat to central Colorado, western South Dakota and southwestern Saskatchewan.


Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah: Perideridia gairdneri ssp. borealis (Synonyms: Atenia montana, Carum montanum, Perideridia montana) - Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah: Perideridia gairdneri ssp. borealis (Synonyms: Atenia montana, Carum montanum, Perideridia montana)

Gairdner's yampah as seen at a vernally moist bald along the Stubblefield Trail about a mile south of the headquarters complex at Turnbull National Wildlife Refuge.......July 4, 2018.

Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah: Perideridia gairdneri ssp. borealis (Synonyms: Atenia montana, Carum montanum, Perideridia montana)

The photo above shows an upper stem leaf and umbel of yampah as seen on rock outcrops below fairly heavy timber along the Chief Joseph Trail in the Eagle Cap Wilderness just west of Wallowa Lake.........July 27, 1997.

Common Yampah, Gairdner's Yampah,Gardner's Yampah, Squawroot, Western False Caraway, Yampah: Perideridia gairdneri ssp. borealis (Synonyms: Atenia montana, Carum montanum, Perideridia montana)

The photo above shows the long, narrow segments of a stem leaf of yampah as seen along the Chief Joseph Trail in the Eagle Cap Wilderness just west of Wallowa Lake.........July 27, 1997.

Paul Slichter