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Key to families | Table of families and genera

Specimen numbers are hyperlinked to records in the Consortium of California Herbaria data view where possible. Taxa are hyperlinked to entries in the Jepson Interchange via the "[Online Interchange]" link.



Joseph R. Rohrer

Shrub, tree. Leaf: simple, alternate or clustered on short-shoots, entire to serrate, generally glabrous, generally glandular on teeth and at blade-petiole junction, veins pinnate; stipules deciduous. Inflorescence: raceme, umbel-like or subsessile cluster, or flowers 1; pedicel bractlets 0. Flower: hypanthium cup- to urn-shaped, deciduous in fruit, bractlets 0; sepals erect to reflexed; stamens generally 10–30, generally in 2+ whorls; pistil 1, ovary superior, chamber 1, ovules 2, style 1, stigma ± spheric or disk-like. Fruit: drupe, generally ovoid to spheric.
200+ species: worldwide, especially northern temperate. (Greek: plum, prune) Seeds of many species ± TOXIC from production of hydrocyanic acid. Many cultivated for wood, ornamental, edible fruit; some persisting near human habitations, some possibly naturalized (e.g., Prunus laurocerasus L.).
Unabridged note: Many cultivated for wood, ornamental, edible fruit; some persisting near human habitation (Prunus armeniaca L., apricot; Prunus avium (L.) L., sweet cherry; Prunus caroliniana (Mill.) Aiton; Prunus cerasus L., sour cherry; Prunus domestica L., plum; Prunus laurocerasus L., laurel cherry; Prunus lusitanica L., Portugal laurel; Prunus mahaleb L.; Prunus munsoniana W. Wight & Hedrick; Prunus speciosa (Koidz.) Nakai; Prunus yedoensis Matsum.).

Key to Prunus

1. Inflorescence an elongate raceme, flowers 15–many

2. Leaves deciduous, finely serrate; inflorescence leafy at base; fruit 6–14 mm ..... P. virginiana var. demissa

2' Leaves evergreen, entire or spiny-serrate; inflorescence leafless at base; fruit 12–25 mm ..... P. ilicifolia

3. Leaf margin spiny-serrate, ± wavy, blade widely ovate to round; petiole 3–10 mm; s North Coast Ranges, Central Western California, Southwestern California (except Channel Islands) ..... subsp. ilicifolia

3' Leaf margin generally entire, flat, blade generally ovate; petiole 8–25 mm; Channel Islands ..... subsp. lyonii

1' Inflorescence a short, ± flat-topped raceme of (3)6–12 flowers, or umbel-like to subsessile cluster of 2–5 flowers, or flowers 1

4. Ovary, fruit generally glabrous

5. Inflorescence a raceme; sepal entire; fruit 7–14 mm; twigs with true terminal bud ..... P. emarginata

5' Inflorescence an umbel-like cluster or flowers 1; sepal gland-toothed to nearly entire; fruit 15–30 mm; twigs with false terminal bud

6. Leaf blade elliptic to (ob)ovate, base obtuse; flowers 1(2), appearing before leaves; tree, roadsides, streambanks, chaparral as waif ..... P. cerasifera

6' Leaf blade oblong-ovate to ± round, base rounded to subcordate; flowers 2–5, appearing with leaves; shrub, mixed-evergreen or conifer forest ..... P. subcordata

4' Ovary, fruit densely puberulent or velvety

7. Tree 3–10 m, not thorny; leaf blade 25–150 mm; fruit 25–80 mm; petals 10–25 mm

8. Petiole (8)10–25 mm; leaf blade 25–100 mm; petals pink to nearly white; fruit pulp leathery ..... P. dulcis

8' Petiole 5–10(15) mm; leaf blade (50)70–150 mm; petals dark pink; fruit pulp fleshy ..... P. persica

7' Shrub < 4 m, often thorny; leaf blade 5–30 mm; fruit 7–18 mm; petals 1.4–12 mm

9. Leaf blade < 2 × longer than wide, base wedge-shaped to rounded or subcordate

10. Leaf blade ovate to obovate, ± hairy, base wedge-shaped to obtuse; flowers generally unisexual; hypanthium, sepals densely puberulent abaxially ..... P. eremophila

10' Leaf blade ovate to round, glabrous, base obtuse to rounded or subcordate; flowers bisexual; hypanthium, sepals glabrous abaxially ..... P. fremontii

9' Leaf blade >= 2 × longer than wide, base long-tapered

11. Petals (5)8–11 mm, dark pink to nearly white; pedicel (1)4–12 mm; leaf blade 2–6 mm wide, finely serrate ..... P. andersonii

11' Petals 1.4–4 mm, white to ± yellow; pedicel 0–4 mm; leaf blade 1–2(4) mm wide, generally entire ..... P. fasciculata

12. Leaf puberulent; s Sierra Nevada Foothills, Tehachapi Mountain Area, s Inner South Coast Ranges, n Transverse Ranges, e Peninsular Ranges, Desert ..... var. fasciculata

12' Leaf glabrous to low-papillate; s Central Coast, s Outer South Coast Ranges ..... var. punctata


Citation for the whole project: Jepson Flora Project (eds.) [year] Jepson eFlora, [accessed on month, day, year]
Citation for an individual treatment: [Author of taxon treatment] [year]. [Taxon name] in Jepson Flora Project (eds.) Jepson eFlora, [URL for treatment]. Accessed on [month, day, year].
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