How to Manage and Identify Green Ash

Fraxinus pennsylvanica
Jerzy Opioła/Wikimedia Commons/CC BY 3.0

Green ash will reach a height of about 60 feet with a spread of 45 feet. Upright main branches bear twigs which droop toward the ground then bend upward at their tips much like Basswood. The glossy dark green foliage will turn yellow in the fall, but color is often muted in the south.

There is a good seed-set annually on female trees which are used by many birds but some consider the seeds to be messy.

This fast growing tree will adapt to many different landscape conditions and can be grown on wet or dry sites, preferring moist. Some cities have over-planted green ash.

Specifics:

Scientific name: Fraxinus pennsylvanica
Pronunciation: FRACK-sih-nus pen-sill-VAN-ih-kuh
Common name(s): Green Ash
Family: Oleaceae
USDA hardiness zones: 3 through 9A
Origin: Native to North America Uses: large parking lot islands; wide tree lawns; recommended for buffer strips around parking lots or for median strip plantings in the highway; reclamation plant; shade tree;
Availability: generally available in many areas within its hardiness range.

Native Range:

Green ash extends from Cape Breton Island and Nova Scotia west to southeastern Alberta; south through central Montana, northeastern Wyoming, to southeastern Texas; and east to northwestern Florida and Georgia.

Description:

Leaf: Opposite, pinnately compound with 7 to 9 serrate leaflets that are lanceolate to elliptical in shape, entire leaf is 6 to 9 inches long, green above and glabrous to silky-pubescent below.

Crown uniformity: Symmetrical canopy with a regular (or smooth) outline, and individuals have more or less identical crown forms.

Trunk/bark/branches: Grow mostly upright and will not droop; not particularly showy; should be grown with a single leader; no thorns.

Breakage: Susceptible to breakage either at the crotch due to poor collar formation, or the wood itself is weak and tends to break.

Flower and Fruit:

Flower: Dioecious; light green to purplish, both sexes lacking petals, females occurring in loose panicles, males in tighter clusters, appear after the leaves unfold.

Fruit: A single-winged, dry, flattened samara with a slender, thin seed cavity, maturing in autumn and dispersing over winter.

Special Uses:

Green ash wood, because of its strength, hardness, high shock resistance, and excellent bending qualities, is used in specialty items such as tool handles and baseball bats but is not as desirable as white ash. It is also a favorite tree used in city and yard landscapes.

Several Green Ash Hybrids:

‘Marshall Seedless’- some seeds, yellow fall color, fewer insect problems,; ‘Patmore’ - excellent street tree, straight trunk, good yellow fall color, seedless; ‘Summit’ - female, yellow fall color, straight trunk but pruning required to develop strong structure, abundant seeds, and flower galls can be a nuisance; ‘Cimmaron’ is a new plant (USDA hardiness zone 3) reported to have a strong trunk, good lateral branching habit, and tolerance to salt.

Damaging Pests:

Borers: common on Ash and they can kill trees. The most common borers infesting Ash are Ash borer, lilac borer, and carpenterworm.

Ash borer bores into the trunk at or near the soil line causing tree dieback.

Anthracnose: also called leaf scorch and leaf spot. Infected parts of the leaves turn brown, especially along the margins. Infected leaves fall prematurely. Rake up and destroy infected leaves. Chemical controls are not practical or economical on large trees. Trees in the south can be severely affected.

More Description:

Green ash (Fraxinus pennsylvanica), also called red ash, swamp ash, and water ash is the most widely distributed of all the American ashes. Naturally a moist bottom land or stream bank tree, it is hardy to climatic extremes and has been widely planted in the Plains States and Canada. The commercial supply is mostly in the South. Green ash is similar in property to white ash and they are marketed together as white ash.

The large seed crops provide food to many kinds of wildlife. Due to its good form and resistance to insects and disease, it is a very popular ornamental tree.