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.

ROSA

Barbara Ertter

Shrub to vine, often thicket-forming, generally prickly
Leaves generally odd-pinnately compound; stipules generally attached to petiole, generally gland-margined
Inflorescence: generally ± cyme or flowers solitary
Flower: hypanthium urn-shaped; bractlets 0; sepals 5, often with long expanded tip; petals generally 5 (except cultivars), generally pink in CA (white to red or yellow); stamens generally > 20; pistils generally many, ovaries superior, jointed to generally hairy styles
Fruit: bony achenes enclosed in fleshy, generally reddish hypanthium (hip)
Species in genus: 100+ species: generally n temp
Etymology: (Latin: ancient name)
Spp. hybridize freely; other non-natives established locally.

Native

R. californica Cham. & Schldl.

CALIFORNIA ROSE

Shrub 8–25 dm, often thicket-forming
Stem gray-brown; prickles generally few, compressed, generally strongly curved
Leaf: leaflets ± hairy, sometimes glandular; terminal leaflet generally 15–60 mm, ± elliptic, tip ± obtuse, margins single- or double-toothed, glandular or not
Inflorescence 1–20-flowered; pedicels generally ± 5–20 mm, generally ± hairy, glandless
Flower: hypanthium 3–5 mm wide at flower, glabrous or sparsely hairy, neck 2–5 mm wide; sepals glandular or not, entire, tip generally ± = body, entire; petals generally 10–20 mm; pistils > 10
Fruit 8–20 mm wide
Chromosomes: n=14
Ecology: Generally ± moist areas, especially streambanks
Elevation: < 1600 m.
Bioregional distribution: California Floristic Province (except High Cascade Range, High Sierra Nevada)
Distribution outside California: s Oregon, n Baja California
Needs study
Horticultural information: SUN or part SHD: 5, 6, 15, 16, 17 &IRR: 2, 7, 8, 9, 10, 14, 18, 19, 20, 21, 22, 23, 24; INV; also STBL.