Fraxinus anomala
Single-leaf ash, Single-Leaf Ash
(c) Jim Morefield, some rights reserved (CC BY) · licence
Family: Oleaceae · Type: Shrub / Tree · Native
Fraxinus anomala (Single-leaf ash) is a native California shrub / tree in the Oleaceae family, recognized by . Simple vs compound leaves diagnostic.
Single-leaf ash is a California native shrub found in northern and eastern desert mountains in washes, rocky slopes, shrubland, and pinyon-juniper woodland at elevations of 1,100 to 2,400 meters. Flowering from April to May, this plant produces yellow-green flowers in compact clusters with glandular-puberulent bracts. Growing as a multi-stemmed shrub to small tree 1.5 to 5 meters tall with gray bark and distinctively 4-angled tan twigs, it develops a complex branching structure. Its leaves are uniquely simple or compound, with blades that are narrowly ovate to rounded, featuring 3 to 5 leaflets each 2 to 10 centimeters long and thick with a yellow-green coloration. The fruit is an elongated wing-like structure 13 to 24 millimeters long, broadly winged and oblong-oblanceolate in shape.
Identification and appearance
Key characters: Geographically isolated with 0 sympatric species. Simple vs compound leaves diagnostic.
Habitat and range
Habitat: Washes, rocky slopes, shrubland, pinyon/juniper woodland
Elevation: 1100-2400 m
California counties: San Bernardino, Inyo
Outside California: to Colorado, New Mexico
Bloom period
Fraxinus anomala blooms Apr-May.
How to tell it apart
vs Sambucus: Fraxinus has winged paddle fruits; Sambucus has clusters of small round berries.; vs Acer: Fraxinus fruits have one wing each; Acer fruits have paired wings joined at base.; vs Quercus: Fraxinus has opposite compound leaves; Quercus has alternate simple leaves and acorns.; vs Juglans: Fraxinus fruits are flat winged paddles; Juglans fruits are round walnuts in green husks.; vs Ailanthus: Fraxinus has opposite leaves with toothed leaflets; Ailanthus has alternate leaves with smooth-edged leaflets.
Frequently asked questions
Is Fraxinus anomala native to California?
Yes. Fraxinus anomala is native to California (recorded as native).
When does Fraxinus anomala bloom?
Fraxinus anomala blooms Apr-May.
Where in California does Fraxinus anomala grow?
Fraxinus anomala occurs in San Bernardino, Inyo, at elevations of 1100-2400 m.
What plant family does Fraxinus anomala belong to?
Fraxinus anomala is in the Oleaceae family, genus Fraxinus.
What habitat does Fraxinus anomala grow in?
Fraxinus anomala grows in Washes, rocky slopes, shrubland, pinyon/juniper woodland.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.