Jepson eFlora
Key to families | Table of families and genera

Key to Ulmus

View taxon page for Ulmus

1. Leaf 1–3.5 cm wide, obtuse, acute, or short-acuminate, margin simply or occasionally doubly serrate

2. Bark not furrowed, peeling as irregular woody scales 2–8 cm wide, orange-brown where freshly exposed, soon weathering ash-gray; flowers, fruit in autumn ..... U. parvifolia

2' Bark deeply furrowed, remaining firmly attached, medium gray; flowers, fruit appearing before leaves in spring ..... U. pumila

1' Leaf 3.5–8.3 cm wide, acuminate, margin doubly serrate

3. Pedicel 7–17 mm, slender; flower, fruit drooping; fruit wing margin densely ciliate; bark split into ridges that mostly curve together at their ends; branches never with corky outgrowths ..... [U. americana]

3' Flower, fruit sessile or nearly so; fruit including wings glabrous except for pubescence on stigmatic surface in notch; bark split into ridges or plates that seldom curve together; generally some branches with corky warts or wings ..... [U. minor]


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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