FABACEAE

LEGUME FAMILY

Annual to tree
Leaves generally compound, alternate, stipuled; leaflets generally entire
Inflorescence: generally raceme, spike, umbel or head; flowers sometime 1–2 in axils
Flowers generally bisexual, generally bilateral; hypanthium generally flat or cup-like; sepals generally 5, fused; petals generally 5, free, or the 2 lower ± fused; stamens 1–many, often 10 with 9 filaments at least partly fused, 1 (uppermost) free; pistil 1, ovary superior, generally 1-chambered, ovules 1–many, style, stigma 1
Fruit: legume, sometimes including a stalk-like base above receptacle, dehiscent, or indehiscent and breaking into 1-seeded segments, or indehiscent, 1-seeded, and achene-like
Seeds 1–several, often ± reniform, generally hard, smooth
Genera in family: ± 650 genera, 18,000 species: worldwide; with grasses, requisite in agriculture and most natural ecosystems. Many cultivated, most importantly Arachis , peanut; Glycine , soybean; Phaseolus , beans; Medicago ; Trifolium ; and many orns
Reference: [Polhill & Raven (eds) 1981 Advances in legume systematics; Allen & Allen 1981 Leguminosae]
Family description and key to genera by Duane Isely.

CAESALPINIA

Elizabeth McClintock

Perennial, shrub, tree, armed or not, gland-dotted or not
Leaves odd- or even-2-compound, alternate
Inflorescence: generally raceme, axillary or terminal
Flower ± bilateral; sepals ± free, overlapped above; stamens 10, ± exserted, free
Fruit dehiscent or not, inflated or flat
Species in genus: ± 200 species: tropical, warm temp; some cultivated
Etymology: (A. Caesalpini, Italy, 1519–1603)
Reference: [Isely 1975 Mem New York Bot Garden 25(2):33–51]

Native

C. virgata Fisher

Shrub 0.5–2 m, hairy; branches slender, generally leafless, rush-like, green
Leaves deciduous; 1° leaflets 3, ternately arranged, lateral pair 0.5–1 cm, with 3–6 pairs of 2° leaflets, terminal 1.5–4 cm, with 8–10 pairs of 2° leaflets
Inflorescence 5–15 cm, few-flowered, puberulent
Flower: sepals 5–6 mm; petals 6–8 mm, banner yellow with reddish marks, later entirely reddish; stamens ± 8 mm, slightly exserted, yellow
Fruit dehiscent, 1.5–2.5 cm, sickle-shaped, with sessile or short-stalked glands especially when young, margins ciliate
Ecology: Uncommon. Gravelly or sandy desert gullies, washes, or canyon slopes
Elevation: 100–500 m.
Bioregional distribution: Sonoran Desert
Distribution outside California: to Texas, Baja California
Flowering time: Mar–May
Synonyms: Hoffmannseggia microphylla Torr
Horticultural information: DRN, DRY, SUN: 8, 9, 10, 11, 12, 13, 14, 19, 20, 21; DFCLT
Recent taxonomic note: Hoffmannseggia microphylla Torr.