Green Ash

Neither moss nor lichens are harmful to the tree, but the stem does provide good habitat for the other species. The holes you can see on the trunk were created by wood boring. The most common culprits are the ash bark beetles and the emerald ash borers. Both of these pests have caused declines in green ash trees. Green ash tree foliage is dark green in the spring and summer time. The leaves are pinnately compound, which means they have multiple leaflets. Green ash leaves have an odd number of lanceolate shaped leaflets (usually 7), with one leaflet located on the end of the leaf’s central stem and the other 6 are paired on either side.

The prime season for green ash flowering is the springtime, from March to May. Flowers will bloom about 2 weeks before the development of the leaves. The flowers are cross-pollinated by the wind. Flowers on green ash trees are light green to purplish in color. These flowers will grow in loose panicles and bloom in early spring. The small clusters of petal-less, tubular flowers are usually less than 1 inch. Male and female flowers bloom on separate trees, making this plant dioecious. During the fall time, when the temperatures cool, the green ash foliage will begin to turn a yellow color before turning a purplish-red. This feature makes the green ash a desirable ornamental tree. As the leaves die, they become brown and begin to fall from the tree. As the female flowers mature post fertilization, they develop into papery fruits called samaras. Samaras have a single, paddle-shaped wing, so you may have heard them described as a “helicopter seed” when you were a child. These are 1-2 inches in length, with a flattened appearance. The seeds mature in the autumn and are wind dispersed in the fall and winter, usually beginning in October.

In the environment, these trees are excellent habitats for animals, as their fruits and seeds give animals food. green ash trees grow well in a variety of climates, which makes them great for landscaping. As their seedlings do cause somewhat of a lawn mess, it is possible to obtain a green ash that has been modified to not produce offspring. Green ash wood is also used for oars and canoe paddles.

These resources are a product of Dr. Sara Wright’s Plant Diversity course in the Biological and Biomedical Sciences Department. My name is Cassandra Nowak, and I will earn my Biology degree in 2023. I plan to continue my education in Biology. You can read more about me and the Green Ash Tree below.