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Fraxinus
ASH

Higher Taxonomy
Family: OleaceaeView DescriptionDichotomous Key

Common Name: OLIVE FAMILY
Habit: Perennial herb to tree [vine], hairs 0 or peltate or not; rarely dioecious. Leaf: simple to odd-pinnately compound, alternate or generally opposite, deciduous or evergreen; stipules 0. Inflorescence: various; flowers >= 1. Flower: generally bisexual, generally radial; calyx generally minute (0), tube cup-shaped, lobes 4--15; petals (0)4--6(8), generally fused; nectar disk often present; stamens (0)2(4--5), epipetalous; pistil 1, ovary superior, chambers 2, each 2--4 ovuled, placenta axile, style 1, stigma generally 2-lobed. Fruit: drupe, capsule, or winged achene. Seed: 1 per chamber.
Genera In Family: +- 25 genera, 900 species: +- worldwide; some cultivated for ornamental (Forsythia; Jasminum, jasmine; Ligustrum, privet; Syringa, lilac) or food (Olea, olive).
eFlora Treatment Author: Family description, key to genera by Thomas J. Rosatti; treatment of genera by James Henrickson, except as noted
Scientific Editor: Bruce G. Baldwin.

Fraxinus
Habit: Shrub or tree; generally dioecious, often bisexual (in California). Stem: older bark smooth or becoming furrowed, generally gray; lenticels broadly elliptic; twigs cylindric to 4-angled, glabrous to hairy; developing short-shoot spurs. Leaf: simple or generally odd-pinnate, opposite, deciduous; petioles channeled, occasionally winged, hairy or not; if compound, leaflets (1)3--9, lanceolate to ovate or obovate, generally acute to acuminate at tip, entire or +- crenate-serrate, generally dark green adaxially, pale abaxially, thin to +- leathery in drier habitats, generally glabrous or with simple hairs abaxially or throughout, proximal opposite on rachis, stalked or not, terminal generally largest, stalk longer. Inflorescence: axillary, of clusters or long-branched panicles; flowers pedicelled. Flower: unisexual or bisexual; calyx 1--2 mm, shallowly +- 4-lobed to cut, persistent on fruit; petals 0, 2, or 4, free or fused to basal filaments. Staminate Flower: stamens 2(3); pistil vestigial. Pistillate Flower: stamens 0; style slender; ovules 2 per chamber. Fruit: achenes, winged, wings generally flat, extending to tip or base of seed-containing chamber. Seed: generally 1.
Species In Genus: +- 65 species: temperate. North America, Eurasia, tropical Asia. Etymology: (Latin: ancient name) Note: Fraxinus uhdei (Wenzig) Lingelsheim, Mexican ash, cultivated in western United States; similar to Fraxinus velutina, with +- larger leaves and leaflets, generally with stiff hairs to 0.5 mm bordering abaxial midvein and occasionally 2° veins abaxially (as occasionally in Fraxinus velutina), and +- larger fruit, but margins tapered to near base of fruit body; native northern Mexico to Honduras.
eFlora Treatment Author: Family description, key to genera by Thomas J. Rosatti; treatment of genera by James Henrickson
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Citation for this treatment: Family description, key to genera by Thomas J. Rosatti; treatment of genera by James Henrickson 2016. Fraxinus, in Jepson Flora Project (eds.) Jepson eFlora, http://ucjeps.berkeley.edu/cgi-bin/get_IJM.pl?tid=9747, accessed on April 30, 2016.

Citation for the whole project: Jepson Flora Project (eds.) 2016. Jepson eFlora, http://ucjeps.berkeley.edu/IJM.html, accessed on April 30, 2016.


Fraxinus velutina
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© 2013 Neal Kramer
Fraxinus anomala
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© 2011 Steve Matson
Fraxinus dipetala
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© 2009 Keir Morse
Fraxinus anomala
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© 2011 Steve Matson
Fraxinus dipetala
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© 2014 Neal Kramer
Fraxinus dipetala
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© 2014 Neal Kramer

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