TREATMENT FROM THE JEPSON MANUAL (1993) |
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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 1many 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 80:686699; 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 1many-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: 12 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, 16581740)
Reference: [Detling 1939 Amer Midl Naturalist 22: 481520]
Relationships, characters of species difficult.May be TOXIC to livestock .
Native D. pinnata (Walter) Britton
Annual; hairs sparse to dense, multibranched
Stem 17 dm; branches 0, below, or above
Leaves lanceolate or oblanceolate to ovate; lower cauline leaves 2-pinnately lobed; upper leaves 110 cm, ± 12-pinnately lobed or 1-compound; lobes or leaflets linear to widely obovate, hairs glandular or not
Flower: petals 13.5 mm, bright yellow to cream
Fruit 420 mm, oblong to ± club-shaped; pedicel ascending to spreading, 420 mm
Seeds 520 per chamber, 2 rows per chamber, 0.51 mm
Ecology: Washes, slopes, often saline soils
Elevation: < 2500 m.
Bioregional distribution: Cascade Range, s High Sierra Nevada, Great Central Valley, Central Coast, San Francisco Bay Area, South Coast Ranges, Southwestern California, Great Basin Floristic Province, Desert
Distribution outside California: widespread N.America
8 difficult subspp.
Native subsp. glabra (Wooton & Standl.) Detling
Stem 14 dm, generally branched from base, ± canescent below, ± glabrous above
Leaf ± 12-pinnately lobed; lobes oblanceolate to obovate, obtuse at tip, greenish; hairs dense
Flower: sepals 0.51.5 mm, ± < petals, yellow or rose; petals yellow
Fruit 58 mm, oblong to ± club-shaped; pedicel ± 60110° from inflorescence axis, 412 mm
Seeds 812 per chamber, ± 0.5 mm
Chromosomes: 2n=28
Ecology: Sandy or saline soils, dry washes, desert scrub
Elevation: < 1500 m.
Bioregional distribution: s San Joaquin Valley, South Coast Ranges, White and Inyo Mountains, Desert
Distribution outside California: to New Mexico, n Mexico
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