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What does EAB Look Like?
What does an Ash Tree Look Like?
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What does an Ash Tree Look Like?

An ash tree is most easily identified by:

1. It has an opposite branching pattern (two branches come off the main stem, one on each side and directly opposite each other)

2. It has compound leaves with 5-11 leaflets (depending on the species of ash). Leaflets are moderately toothed and may be stalked or sessile.

3. In winter: first look for the opposite branching pattern and stout twigs of ash. Small branches grow off larger branches opposite one another. Likewise, buds and leaf scars are opposite one another on twigs.

Next, Ash trees have many small dots (vascular bundles) on their leaf scars, forming a semi-circle or crescent pattern.

And, white and green ashes have thick, diamond-patterned bark, while black ash bark is thin, ashy-gray, and scaly.

Ash species attacked by emerald ash borer include green (Fraxinus pennsylvanica), white (F. americana), black (F. nigra), and blue (F. quadrangulata), as well as horticultural cultivars of these species. Green and white ash are the most commonly found ash species in the Midwest with blue ash being rare. Note: blue ash twigs are 4-sided. All other Wisconsin ash trees have round stems.

While other woody plants, such as mountain ash and prickly ash, have 'ash' in their name, they are not true ash (Fraxinus species). Therefore they are not susceptible to attack by emerald ash borer.

Ash trees are abundant in Wisconsin, with estimates as high as 765 million trees in forests and over 5 million in urban areas. Ash is a component of three forest types in Wisconsin including 1) Elm / Ash / Cottonwood, 2) Northern Hardwood and 3) Oak / Hickory.

Ash wood is used for making flooring, baseball bats, tool handles, cabinets and much more.

Related Documents
Ash Tree Identification (This document outlines how to recognize an ash tree. By Michigan State University Extension, in PDF format.)

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Related Images

Example of the diamond pattern typical of green and white ash bark. This photo is of a green ash tree. WDNR Photo by Brian Schwingle

Opposite branching pattern of ash trees. WDNR Photo by Renee Pinski

Black ash twig, showing nearly black buds (with the first lateral buds some distance below terminal buds). Also showing the unique oval leaf scar shape of black ash. WDNR Photo by Brian Schwingle

Green ash twig, showing leaf scars with straight upper edges, fuzzy or velvety new growth, and reddish-brown buds. DNR Photo by Brian Schwingle
Note: White ash leaf scars are crescent-shaped (i.e. notched along the upper edge).

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