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.

IVESIA

Barbara Ertter

Perennial, glandular; odor resinous
Leaves generally basal, odd-1-pinnate, generally ± cylindric; cauline reduced; leaflets generally overlapped, generally divided ± to base
Inflorescence: cyme
Flower: hypanthium shallow or deep; bractlets (0)5, generally < sepals; sepals generally 5; petals generally 5, acute to rounded; stamens generally < or = 20; pistils 1–many, ovaries superior, style jointed below fruit tip, base ± rough-thickened
Fruit: achene
Species in genus: 30 species: w North America
Etymology: (E. Ives, Yale Univ. pharmacologist, 1779–1861)
Reference: [Ertter 1989 Syst Bot 14:231–244]
Lf and leaflet data are for basal leaves.

Native

I. gordonii (Hook.) Torr. & A. Gray

Plant tufted, green; caudex 0–few-branched
Stem ascending to erect, 5–20 cm
Leaf generally 3–8 cm; sheathing bases ± glandular; leaflets generally 10–16 per side, overlapped but distinct, lobes 4–8, generally 2–5 mm, oblanceolate to obovate; cauline leaf generally 1
Inflorescence: cluster generally 1, 10–30 mm wide, head-like, 10–20-flowered; pedicels generally < 3 mm, straight
Flower ± 5 mm wide; hypanthium length = or > width; petals 2–3 mm, narrowly oblanceolate, yellow; stamens 5; pistils generally 2–4
Fruit ± 2 mm, ± smooth, mottled brown
Ecology: Open, dry, rocky ridges, slopes
Elevation: 1800–3500 m.
Bioregional distribution: Klamath Ranges, High North Coast Ranges, n&c High Sierra Nevada, Warner Mountains, n East of Sierra Nevada (Sweetwater Mtns)
Distribution outside California: to Washington, Wyoming, Colorado
Flowering time: Jul–Aug
Horticultural information: TRY; DFCLT.