Blue ash is a deciduous tree native to the midwestern U.S.A. in the olive family (Oleaceae). The species epithet is Latin for “four-angled” and refers to the young twigs, which bear four longitudinal ridges or low wings giving the twig a four-sided appearance. Blue ash is found growing in both damp and dry conditions and tolerates growing on limestone substrates better than other ash trees. It prefers full sun and is not picky about soil types. Unlike some ash trees, blue ash dislikes flooded conditions and tolerates alkaline soils. This tree will grow 50 to 60 feet tall with an oval to pyramidal form. The common name of blue ash comes from a dye that was extracted from the bark and used to color yarn by the early settlers. This tree has also suffered from the emerald ash borer but seems to be the least affected in comparison to other North American ash trees. Insects, Diseases, and Other Plant Problems: Emerald ash borer. It can be more difficult to propagate and slower to establish than other ash trees. See potential insect and disease problem factsheets to the left. VIDEO created by Grant L. Thompson for “ Trees, Shrubs, and Woody Vines for Landscaping ” a plant identification course offered by the Department of Horticulture at Iowa State University . More information on Fraxinus .
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Clay; Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist | Occasionally Dry
Available space
more than 60 feet
Mature size
Height: 50 ft. 0 in. - 70 ft. 0 in. | Width: 50 ft. 0 in. - 70 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
1 - Canopy (>40 ft)
Form & Appearance
Habit / form
Erect; Oval; Pyramidal
Texture
Medium
Foliage
Deciduous
Leaf color
Gold/Yellow
Leaf type
Compound (Pinnately , Bipinnately, Palmately)
Leaf arrangement
Opposite
Leaf shape
Lanceolate; Ovate
Leaf margin
Serrate
Leaf feel
Smooth
Leaf size
3-6 inches long, 1-3 inches wide
Hairs present
Yes
Leaf detail
The green opposite compound leaves have 5-11 leaflets, most often 7-9, that may have a few hairs on the underside. Each leaflet is 2-5 by 1-2 inches. They have short stems and are oval to lanceolate in shape. The margins are serrated. Fall color is a pale yellow.
Fall color
Gold/Yellow
Flower color
Purple/Lavender
Flower form
Insignificant
Flower detail
A panicle of very small insignificant flowers in spring
Bloom time
Spring
Fruit color
Brown/Copper
Fruit type
Samara
Fruit size
1-3 inches long, < 1 inch wide
Fruit detail
Winged samaras in clusters. Individuals are 1–1½" long, ¼–½" across
Bark color
Light Brown; Light Gray
Bark detail
Gray to gray-brown bark with furrows and short irregular ridges
Stem color
Brown/Copper; Gray/Silver
Stem detail
4-sided twigs are corky and buds are gray to brown. May be slightly pubescent
Wildlife & Ecology
Native status
Unknown
Origin
North and East central U.S.A.
Distribution
AL , AR , GA , IA , IL , IN , KS , KY , MI , MN , MO , MS , OH , OK , TN , VA , WI , WV
Wildlife value
Birds and mammals will eat the seeds. Tadpoles feed on the fallen leaves. Many moths and butterfly larvae will eat the leaves.
Attracts
Butterflies; Frogs; Moths; Small Mammals; Songbirds