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. pickeringii A. Gray

PICKERING'S IVESIA

Plant tufted, grayish, long-spreading-hairy; caudex 0–few-branched
Stem ascending to erect, 30–50 cm
Leaf 10–20 cm; sheathing bases strigose; leaflets 35–50 per side, overlapped but distinct, lobes generally 3–5, 2–5 mm, oblanceolate to obovate; cauline leaves 5–10
Inflorescence open; flowers many, generally separate; pedicels 2–10 mm, straight
Flower ± 10 mm wide; hypanthium length ± = width; petals 3–5 mm, ± oblanceolate, white or pink-tinged, > sepals; stamens 20; pistils 2–4
Fruit 2.5–3 mm, smooth, dark brown
Chromosomes: 2n=28
Ecology: Wet, rocky meadows, generally on serpentine clay
Elevation: 800–1500 m.
Bioregional distribution: c Klamath Ranges
Horticultural information: In cultivation.