Jepson eFlora
Key to families | Table of families and genera

Key to Acer

View taxon page for Acer

Jepson Manual glossary definitions can be seen by moving your cursor over words underlined with dots.

1. Leaf compound, leaflets stalked; inflorescence axillary, pendent panicle ..... A. negundo

1' Leaf simple, palmately lobed, or compound with leaflets sessile; inflorescence not a pendent panicle

2. Abaxial leaf surface white or ± white-green; flowers present before leaves, in dense clusters; petals 0 ..... A. saccharinum

2' Abaxial leaf surface green; flowers present with leaves, inflorescence cyme, raceme, or panicle; petals present

3. Leaf lobes 7–9 ..... A. circinatum

3' Leaf lobes 3–5

4. Leaf 10–25 cm wide; inflorescence pendent, flowers 20–90 ..... A. macrophyllum

4' Leaf 1.4–10 cm wide; inflorescence ascending, flowers 2–30

5. At least leaf veins, margins pubescent; each lobe with 0–1(2), large, rounded teeth per side; fruit wings widely spreading 160–200° ..... [A. campestre]

5' Leaf glabrous; each lobe with 3–many, small, sharp teeth per side; fruit wings overlapping or spreading (40)70–120° ..... A. glabrum

6. Petiole 0.9–2.4 cm, blade 1.4–2.8 cm, 2–3.5 cm wide; lobes rounded or obtuse, lateral lobes with 3–7 obtuse to acute teeth on outer side ..... var. diffusum

6' Petiole 2.8–9.7 cm, blade 2.9–5.6 cm, 3.6–6.3 cm wide; lobes acute, lateral lobes with 5–22 acute to apiculate teeth on outer side ..... var. glabrum


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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