This is a medium sized tree with a height to 80 feet tall and a width of 2 ft. It has a short bole and an irregular crown.

Leaves:
 Arrangement: opposite; pinnately compound normally with 7-11 leaflets

 Shape: lanceolate

 Margin: serrated

 Texture: glabrous

 Variation: pinnate

Blue ash bark is brown to ash gray, and rough and scaly when young. When the tree matures it forms irregular fissures and scaly ridges giving a shaggy appearance.

It has a relatively stout twig that is 4-angled. The leaf scars are notched and the buds are gray to reddish brown in color.

The flowers occur in panicles that appear before the leaves. The fruit is a samara, with a wide wing and a flattened seed.

It has opposite compound leaves and the twigs have 4 distinct edges. The inner bark turns blue when exposed to air.

Blue ash is found in Southern Wisconsin west to Ohio, south to northern Georgia and west to eastern Oklahoma.

This species in most common on calciferous dry limestone uplands.

It was once used for blue dye by the pioneers. The wood is used in flooring, baseball bats, furniture, tool handles, barrels and crates.