OXALIDACEAE

OXALIS FAMILY

Robert Ornduff

Annual to tree
Leaves compound (palmate, pinnate, or leaflet 1), alternate, often ± basal in rosettes or in clusters at stem or rhizome tips, generally petioled; stipules generally 0; leaflets generally sessile
Inflorescence: cyme, sometimes umbel- or raceme-like, or flowers solitary, generally in axils; peduncle bracted
Flower generally bisexual, radial; sepals 5, free or fused at base; petals 5, free or fused above base; stamens 10 or 15, fused below, of 2 lengths; pistil 1, ovary superior, chambers 3–5, placentas axile, styles 1–5, generally ± free
Fruit: generally capsule, loculicidal
Seeds generally with aril
Genera in family: 8 genera, 575 species: especially temp. Often heterostylous.

OXALIS

Annual, perennial herb, shrub; roots fibrous or woody; bulbs, tubers, or rhizomes often present
Stem sometimes 0 or very short
Leaf petioled: stipules 0 or small; leaflets 3, generally ± obcordate in CA, generally entire, generally green
Flower: petals clawed; stamens 10; ovary chambers 5, styles 5, free, erect or curved
Fruit cylindric to spheric, explosively dehiscent
Seeds flat, often ridged; aril translucent
Species in genus: ± 480 species: especially temp
Etymology: (Greek: sour)
Reference: [Eiten 1963 Amer Midl Nat 69:257–309; Lourteig 1975 Phytologia 42:57–197]
Generally heterostylous; many (especially aliens in CA except O. laxa ) fine ornamental; some noxious weeds; contained oxalates may be toxic to livestock.

Native

O. trilliifolia Hook.

Perennial; rhizome creeping, thick, scaly; bulbs 0
Stem 0 or very short
Leaves clustered at rhizome tips; petiole < 30 cm, hairy; leaflets < 4 cm
Inflorescence umbel-like, 3–9-flowered; peduncle < 25 cm
Flower: sepals < 5 mm, lanceolate; petals < 1.3 cm, white or pinkish
Fruit < 3 cm, linear
Ecology: Dense conifer forests
Elevation: < 1500 m.
Bioregional distribution: North Coast, Klamath Ranges, Outer North Coast Ranges
Distribution outside California: to Washington
Fls summer
Horticultural information: TRY