ROSACEAE

ROSE FAMILY

Annual to tree
Leaves simple to pinnately to palmately compound, generally alternate; stipules free to fused, persistent to deciduous
Inflorescence: cyme, raceme, panicle, or flowers solitary
Flower generally bisexual, radial; hypanthium free or fused to ovary, saucer- to funnel-shaped, often with bractlets alternate with sepals; sepals generally 5; petals generally 5, free; stamens (0)5–many, pistils (0)1–many, simple or compound; ovary superior to inferior, styles 1–5
Fruit: achene, follicle, drupe, pome, or blackberry- to raspberry-like
Seeds generally 1–5
Genera in family: 110 genera, ± 3000 species: worldwide, especially temp. Many cultivated for ornamental and fruit, especially Cotoneaster , Fragaria , Malus , Prunus , Pyracantha, Rosa , and Rubus
Reference: [Robertson 1974 J Arnold Arbor 55:303–332,344–401,611–662]
Family description, key to genera by Barbara Ertter and Dieter H. Wilken.

OEMLERIA

OSO BERRY

Thomas J. Rosatti

Species in genus: 1 sp
Etymology: (derivation unknown)
Reference: [Landon 1975 Taxon 24:200]

Native

O. cerasiformis (Hook. & Arn.) J.W. Landon

Shrub or small tree, 1–5 m, ± dioecious
Leaves deciduous, 5–13 cm, elliptic to narrowly obovate, generally entire, ± rolled under, paler below, glabrous above; stipules soon deciduous; petiole 5–15 mm
Inflorescence: racemes on short lateral branches, 3–10 cm, pendent, bracted; bractlets 1–2 at pedicel tip
Flowers fragrant (generally some bisexual); hypanthium ± 5 mm; petals clawed, white
Staminate flower: hypanthium persistent; petals spreading, > pistillate petals; stamens 15, prominent
Pistillate flower: most of hypanthium deciduous; petals erect; ovaries generally 5, prominent, free, superior, styles deciduous
Fruit: drupes 1–5 per pistillate flower, 5–15 mm, bean-shaped, blue-glaucous
Chromosomes: n=8
Ecology: Shaded coniferous forest, chaparral
Elevation: < 1700 m.
Bioregional distribution: Northwestern California, w Cascade Range, w Sierra Nevada, Sacramento Valley (Sutter Buttes), south-central San Joaquin Valley, w Central Western California, sw Western Transverse Ranges
Distribution outside California: to British Columbia
Synonyms: Osmaronia c. (Hook. & Arn.) Greene
Horticultural information: partSHD: 4, 5, 6, 15, 16, 17 &IRR: 7, 8, 9, 14, 18, 19, 20, 21, 22, 23, 24.