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Shasta Clarkia
(Clarkia borealis ssp. arida )
Onagraceae (evening primrose family)

Shasta Clarkia
Photo by Joe Molter, BLM



Distribution: Southern Cascade range, Shasta and Tehama Counties.

Habitat: Openings in foothill pine and black oak woodlands on southerly to westerly gentle slopes.  Largest and most robost in very partial shade with little competing vegetation, at 1600 to 1800 feet (490 to 550 m) in elevation. 

Flowering Period: June through August

Similar Plants: Clarkia rhomboidea and C. borealis ssp. borealis.

Status: BLM Sensitive, California Native Plant Society List 1B


Erect annual, little-branched herb, 15 to 40 inches (0.4 to 1 m) tall.  Leaves more or less entire, elliptic to ovate, 3/4 to 2 inches (2 to 5 cm) long with petiole 5/8 to 2 inches (1.5 to 5 cm) long.  Inflorescence with more than 4 buds along the straight portion betwwen the open flowers and arching tip, buds 11/16 to 15/16 (18 to 24 mm) long.  Flowers lavender-purple with narrow stalk-like based petals 5/16 to 3/4 inch (8 to 19 mm) long.

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Field Office: Redding

Last updated: 08-05-2010