Ash, Green
Fraxinus pennsylvanica
Oleaceae - Olive

Description

Leaves: Opposite; once pinnately compound; 10" to 12" long; deciduous; 7-9 leaflets; leaflets oblong-lanceolate to elliptic, 4" to 6" long, glabrous above and pubescent below, bright green, finely serrate margin, short-stalked; turn bright yellow in fall.

Twigs/buds: Twigs fairly stout; gray to brown; leaf scar half-circular, straight or shallowly notched across the upper edge. Terminal bud rusty brown, conical, hairy; lateral buds smaller.

Flowers/fruit: Flowers dioecious; small and inconspicuous, arranged in clusters; appear in spring as leaves expand. Fruit a samara; 1" to 2-1/2" long, 1/4" wide; paddle-shaped in dense clusters; often clinging to twigs into or throughout the winter; abruptly narrowed wing along the slender seed cavity.

Bark: Ash-gray; sometimes with an orange tinge on younger trees; on older trees furrowed into diamond-shaped areas separated by narrow interlacing ridges; distinctive.
Wood: Important where native; sapwood white; heartwood light brown; growth rings distinct; ring-porous; rays not distinct; used for handles, tools, containers, furniture, lumber, etc.

General: Native from the Great Plains east, including southern Canada. Prefers moist sites, but fairly drought resistant and tolerant of fairly high soil pH. Intermediate shade tolerance. May be insect and/or disease prone, especially when stressed.

Landscape Use: A tough, durable, large tree used extensively in Utah in landscapes since pioneer times. Also good for windbreaks. Lilac borers can be an especially severe problem that is difficult to treat effectively, though they may be most likely to affect stressed trees. I have seen many old green ashes that show no signs of borers, while a nearby young, vigorous, 30' tall tree might be riddled with borers. Seedless cultivars are available, but they can set large amounts of seed under stressful conditions. Zones 3- 9.

In the last few years an exotic pest, emerald ash borer (EAB), has been making its way across the U.S. So far it has decimated populations of ornamental and native ashes and recently was found to attack fringetree (Chionanthus spp.) as well. So far EAB has not made it to Utah, but it seems likely that it will. So, plant ashes and fringetrees with caution since they may not be around for long. Some have hope that trunk injection of insecticides may work to control the pest.

Cultivars: 'Bailey', 'Bergeson', 'Cardan', Centerpoint™, 'Cimmzam', 'Emerald', 'Fanick', 'Harlequin', 'Honeyshade', 'Jewell', 'Johnson', 'Kankakee', 'Kindred', 'King Richard', 'Lednaw', 'Leeds', 'Marshall's Seedless', 'Patmore', 'Rugby', 'Robinhood', Sherwood Glen™, 'Summit', Urbanite®, 'Wahpeton', 'Wandell'.

Characteristics

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