Key to Ulmus

View taxon page for Ulmus

(For a list of species in Ulmus, use the above link.)

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

1. Leaf 1–3.5 cm wide, 

obtuse 

Having a short-tapered, blunt tip or base, the sides convex or straight and converging at more than a right angle.

, 

acute 

Having a short-tapered, sharp tip, the sides convex or straight and converging at less than a right angle.

, or short-acuminate, margin simply or occasionally doubly 

serrate 

Having margins with sharp, fine to coarse teeth generally pointing tipward, not outward; margins with such teeth on such primary teeth are 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 

Having a long-tapered, sharp tip, the sides concave.

, margin doubly serrate

3. Pedicel 7–17 mm, slender; flower, fruit drooping; fruit 

wing 

1. Thin, flat extension or appendage of a surface or margin. 2. In many members of Fabaceae and in some other groups, each of two lateral petals.

margin densely 

ciliate 

Having generally straight, conspicuous hairs along margins or edges.

; bark split into ridges that mostly curve together at their ends; branches never with corky outgrowths ..... [U. americana]

3' Flower, fruit 

sessile 

Without a petiole, peduncle, pedicel, or other kind of stalk.

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]

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