Fraxinus pennsylvanica Marsh.

Oleaceae – Olive Family

Fraxinus pennsylvanica

English: Green ash

Natural History

Green ash has the largest distribution of the genus Fraxinus here in North America, ranging across southern Canada from Alberta to Nova Scotia and south to Texas and Florida. It is not native to Colorado. It is a member of a variety of forest types across its wide range occasionally being dominant, particularly in lowland areas near floodplains. The seeds provide important wildlife food for both birds and small mammals.

Human history and use

The wood of Green ash is quite hard and thus due to its strength it has been used in the production of things like tool handles oars and baseball bats although white ash (F. americana) is the preferred material for bats.

It is widely used horticulturally as a shade tree in residential areas due to its adaptability to a wide range of growing conditions although new use of the tree in horticultural settings is not widely recommended due to its susceptibility to the Emerald ash borer, an insect native to Asia which was introduced to North America, first being seen in Michigan in 2002.  This pest is a threat to all native ash trees here in North America. 

While not widely used medicinally, the inner bark has been used to make an infusion for the treatment of depression and fatigue.

Green ash is the more common of the two species found on the FLC campus and is easily distinguished from the similar White Ash by the leaf scars which are nearly straight across the top as opposed to “U” shaped.


Burns, R. M., and B. H. Honkala. 1990. Silvics of North America: 1. Conifers; 2. Hardwoods.
Agriculture Handbook 654. U.S. Department of Agriculture, Forest Service, Washington, DC.

Dirr, M. 2009. Manual of woody landscape plants: Their identification, ornamental characteristics,
culture, propagation and uses. Stipes Pub

Gucker, C. L. 2005. Fraxinus pennsylvanica. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: /database/feis/plants/tree/frapen/all.html [2022, April 4].

Moerman DE. 1998. Native American Ethnobotany. Portland, OR: Timber Press.

Plant Finder, Missouri Botanical Garden. 2021. Fraxinus pennsylvanica. [2021, October 14].