TREATMENT FROM THE JEPSON MANUAL	previous taxon | next taxon Jepson Interchange (more information)
	©Copyright 1993 by the Regents of the University of California Print edition is available from the University of California Press

	The second edition of The Jepson Manual (2012) is available from the University of California Press
	See also the Jepson eFlora, which parallels the Second Edition

BRASSICACEAE

MUSTARD FAMILY

Reed C. Rollins, except as specified

Annual to subshrub
Leaves generally basal and cauline, alternate, generally simple; stipules 0
Inflorescence: generally raceme
Flower bisexual; sepals 4, free; petals (0)4, free, generally white or yellow, often clawed; stamens generally (2,4)6, generally 4 long, 2 short; ovary 1, superior, chambers generally 2, septum membranous, connecting 2 parietal placentas, style 1, stigma simple or 2-lobed
Fruit: generally capsule ("silique") with 2 deciduous valves, sometimes breaking transversely or indehiscent
Seeds 1–many per chamber
Genera in family: 300+ genera, 3000+ species: worldwide, especially cool regions; some cultivated for food (especially Brassica, Raphanus ) and ornamental
Recent taxonomic note: Recently treated to include Capparaceae [Rodman et al. 1993 Ann Missouri Bot Gard 80:686–699; Rollins 1993 Cruciferae of Continental North America. Stanford Univ Press]
Family description, key to genera by Robert A. Price.

DESCURAINIA

TANSY MUSTARD

Annual, biennial, rarely per; hairs generally minute, generally multibranched, fewer simple, some glandular
Stem branched
Leaves 1–many-pinnately lobed to compound; basal often rosetted but withering
Inflorescence elongating; bracts generally 0
Flower: petals < 3 mm, yellow or whitish, blades obovate, obtuse
Fruit linear to ± obovate, straight or uneven-margined, generally ± cylindric; style < 0.8 mm or 0, stigma generally head-like, entire
Seeds: 1–2 rows per chamber, generally < 1 mm, elliptic, plump, gelatinous when wet; wing 0; embryonic root at back of 1 cotyledon
Species in genus: ± 40 species: worldwide temp
Etymology: (F. Descourain, French botanist, 1658–1740)
Reference: [Detling 1939 Amer Midl Naturalist 22: 481–520]
Relationships, characters of species difficult. May be TOXIC to livestock.

Native

D. incana (Fisch. & C.A. Mey.) Dorn

Biennial, canescent to greenish
Stem 3–12 dm, slender, branched, with glandular hairs or not
Leaves 1.5–10 cm, widely lanceolate or oblanceolate to ovate; basal and lower cauline leaves 1–2-pinnately lobed or -compound, upper simple to 1-pinnate, entire
Flower: petals ± 2 mm, yellow
Fruit 5–25 mm, 0.5–1.5 mm wide, linear, generally straight; both ends acute; pedicel erect to ascending, 2–4(7) mm; style < 1 mm
Seeds 4–8, 1 row per chamber
Chromosomes: 2n=14
Ecology: Open sites, meadows, sagebrush, open aspen groves
Elevation: 1500–3400 m.
Bioregional distribution: Klamath Ranges, Sierra Nevada, San Bernardino Mountains, Great Basin Floristic Province
Distribution outside California: to Alaska, e N.America
Flowering time: May–Aug
Synonyms: D. richardsonii (Sweet) O.E. Schulz; D. r. subsp. viscosa (Rydb.) Detling

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