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.
ISATIS
WOAD
Annual to perennial herb, erect
Leaves simple
Flower small; sepals < petals
Fruit pendent, oblong to round, flat perpendicular to septum, indehiscent, ribbed, 1-chambered; wing ± inflated or not; style 0
Seed 1, pendent, in place of septum
Species in genus: ± 60 species: generally Eurasia, especially Iraq, Iran
Etymology: (Greek: plant with dark dye)
| Introduced |
I. tinctoria L.
Biennial, perennial herb, glaucous
Stem 1, 4–12 dm, simple below, glabrous, ± grayish
Leaves: basal several, clustered, long-petioled, < 2 dm, ± oblanceolate, ± toothed or wavy-margined, hairs sparse, simple; cauline sessile, sagittate, clasping stem, generally entire, glabrous
Inflorescence: panicle of racemes; bracts subtending main branches, leaf-like
Flower: petals ± 3.5 mm, spoon-shaped
Fruit 8–18 mm, 5–7 mm wide, oblong to oblanceolate, black; tip obtuse to rounded; pedicel ascending to reflexed, < fruit, slender
Seed yellowish; embryonic root at back of 1 cotyledon
Chromosomes: 2n=28
Ecology: Roadsides, fields, disturbed sites
Elevation: < 1000 m.
Bioregional distribution: Klamath Ranges, Cascade Range, n High Sierra Nevada, Modoc Plateau
Distribution outside California: to Idaho, Utah, also e US; native to Europe
Once cultivated as source of blue dye.
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