Tour Stop 16: Green Ash Trees

Green Ash Leaves

Green Ash leaves

The tree in front of you is called a Green Ash. This species is found all over North America from Canada to southeastern Texas, especially in the swampy bayou region around Houston. Here in Texas, this fast-growing tree can grow to be 120 feet tall and its bright green leaves will turn purple or yellow in the fall. Because of its strength, hardness, and high shock resistance qualities, ash is used to make flooring, boxes & crates, and turned objects such as tool handles or boating oars. It is also sometimes used to make baseball bats, although they are more typically made out of the closely related White Ash. 

The Green Ash acts as a host plant for the Eastern Tiger Swallowtail butterfly and Polyphemus Moths.

How do we know that this is a Green Ash tree? There are many ways that trees can be identified and distinguished from one another.

● First, you can use the overall form of a tree to aid in identification. The tree's form involves its shape, size, and the pattern of the branches. For example, a Green Ash has a spreading crown of limbs, creating an oval shape.

● The twigs of the Green Ash appear hairy as opposed to the twigs of its close relative the White Ash.

● Next, looking carefully at the leaves can also help you to identify a tree. The Green Ash has compound leaves; that is, each leaf is composed of a central stem with 7 to 9 separate leaflets growing from it. The central stem of the compound leaf may be up to a foot long. These leaves grow directly opposite from each other. The color of the leaf is also important in identification. In this case, the leaf is a dark, glossy green above with a lighter shade of green on the underside.

● The texture, color, and thickness of the tree's bark can also aid identification, especially in winter when many trees lack leaves. The gray to brown bark of the Green Ash has an identifiable pattern of narrow ridges throughout it.

● Finally, where the tree is growing is an important clue. Is it normally found in this part of the state? Does it grow in the sun or shade, or in a wet or dry climate? What kind of soil does it prefer? For example, Green Ash can be distinguished from the very similar Texas Ash due to the fact that Texas Ashes don’t typically grow in the clay-filled gumbo soil of Houston. Texas Ash trees prefer the limestone areas of north central Texas and across the Edwards Plateau.

Trunk of Green Ash Tree with Lichen

Green Ash tree trunk