Single Leaf Ash
Fraxinus anomala
Family: Oleaceae
CHARACTERISTICS
Broadleaf deciduous shrub or small tree, may grow to 5-20’ tall. It is the only ash with simple (not divided) leaves though rarely you may find an individual plant with some leaf divisions. There is a recognized variety of this species (var. lowellii) that has divided leaves.
Flowers bisexual but only half of the plants produce fruit in the wild. Flowers in spring with nondescript brownish flowers that lack petals and usually appear before the foliage. The fruit is a flat samara typical of ashes. Yellow fall color.
LANDSCAPE USE
Screening shrub or small tree.
Fraxinus anomala photo by Martine Lapointe, iNaturalist
Fraxinus anomala on SEINET
GROWING CONDITIONS
AN EXPLANAITION OF TERMS USED
SUN full to part sun, in the low desert afternoon shade in the winter is probably a good idea
WATER in the low desert, regular water is a good idea. This is a canyon-dwelling species, except in the highest elevations
SOIL well-drained improved soil is preferred
BASIN plant in the bottom to middle
CONTAINER does moderately ok in a container but will not attain full size
HARDINESS hardy to -25°F
FEEDING moderate to low
ECOLOGY
This plant is a larval host plant of the two-tailed swallowtail (Papilio multicaudata multicaudata). Because it is a deciduous plant, the soil underneath it is often improved by the annual drop of foliage.
ETHNOBOTANY
Used ceremonially by the Hopi.
NATURAL DISTRIBUTION
Found in canyons and bottomlands in lower elevations, often on dry slopes in higher elevations, ranges from 2,000-8,000’. Native range extends from southeastern California west to Colorado and south into Texas and northern Mexico.
TAXONOMY AND NAME
This plant is in the Oleaceae, the olive family. There are 63 species of Fraxinus widespread throughout much of Europe, Asia, and North America..
Fraxinus is the classical Latin name for the genus, while the species name, anomala, means unusual, or an exception to the rule, referring to the simple leaves in a genus characterized by compound leaves.
Plants are often found in steep canyons throughout its range, photo by brehbeck, iNaturalist
Leaves on this species are often undivided which is rare for a species of Fraxinus and the reason it is referred to as an "anomaly" via its species epitaph. Green fruits developing on this branch, photo by Te Chang, iNaturalist
This soecimen has leaves divided into 3, photo by Matt Berger, iNaturalist
The flowers are small and yellowish green, photo by James Ojascastro, iNaturalist
Plants display yellow to light orange fall color, photo by John Brew, iNaturalist