Ash trees are unique trees that are easily recognized by certain characteristics setting them apart from other trees. For example, their compound leaves and opposite branching are features that make them unique. The tree gets its name from its ash-gray bark which creates a stunning contrast against its delicate green foliage. This type of tree has many benefits, such the fact that it's a fast growing tree that lives long and is able to take a wide variety of soil types. The ash tree is also a valuable hardwood resource.
The ash tree (Fraxinus species) has roughly five to nine leaflets for each leaf. These leaflets have either jagged or smooth margins. The tree produces a fleshy fruit known as a samara that's wing-shaped with reddish-orange berries. Ash trees have creamy white flowers and their bark is decorated with a pattern of diamond shaped ridges. Seeds are oar shaped and hang in clusters from the trees until late fall or early winter.
The ash tree originated from Great Britain, as well as most of greater Europe. In North America ash trees are mostly found in growing zones 3 and 4, according to the University of Minnesota Extension website. Green and white ash varieties are usually found in the Midwest.
According to the Colorado State Extension website, green ash and white ash are two types of ash trees that are sold commercially. Green ash trees are more tolerant to cold weather, more adaptable and have golden fall foliage. The three common green ash varieties are Patmore, Summit and Marshall's Seedless. While Patmore is seedless and has an oval to pyramidal shape, Summit is more erect and produces some seeds. Marshall's Seedless is seedless, more rounded, and isn't as cold hardy as the other two green ash varieties. White ash trees have purplish foliage in fall. The Autumn Purple variety is seedless.
Pests and Diseases
The most damaging pests that bother the ash tree are the wood boring insects such as the emerald ash borer. Other common pests include moths, beetles and fly larvae. Fungal diseases are the most common ash tree disease. Although diseases and insects can destroy foliage causing growth loss, these problems rarely do widespread damage.
Ash trees are often injured by fall or spring snowstorms. Continued damage from storms can result in deformed trees. They need pruning every three to four years for maintaining proper structure and form.
The numerous seeds produced by female ash trees can be messy when they fall on other areas of a landscape.