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. baileyi S. Watson

Plants hanging clumps, green
Stem 5–20 cm
Leaf generally 3–10 cm, ± flat; sheathing bases ± glabrous; leaflets 2–6 per side, ± separated, ± 4–10 mm, ± round, toothed ± < 1/2 to base; cauline leaves 1–2
Inflorescence open, often > 10-flowered; pedicels generally 2–12 mm, S-shaped in fruit
Flower 4–8 mm wide; hypanthium length < 1/2 width; petals 1.5–2 mm, ± oblanceolate, pale yellow or white, < sepals; stamens 5; pistils 1–6
Fruit ± 1.5 mm, pale
Ecology: Volcanic crevices
Elevation: 1600–2600 m.
Bioregional distribution: Modoc Plateau, adjacent High Sierra Nevada
Distribution outside California: to se Oregon, s Idaho, n Nevada

Native

var. baileyi

BAILEY'S IVESIA

Leaf: sheathing base ± glabrous
Inflorescence: pedicels 2–12 mm
Flower: bractlets ± = sepals; petals pale yellow
Fruit smooth
Ecology: Habitats and elevations of sp.
Bioregional distribution: s Modoc Plateau, adjacent High Sierra Nevada
Distribution outside California: nw Nevada