Green Ash (Fraxinus pennsylvanica): Fast-Growing Shade and Windbreak Tree

Species Overview

Green Ash (Fraxinus pennsylvanica), also called Red Ash, Downy Ash, Water Ash, or Swamp Ash, is a native North American species ranging from Nova Scotia to Alberta, south to Florida and Texas. Its rapid growth on moist sites and extreme climate resilience make it a landscape workhorse.

Identification

• Size: Medium deciduous tree, 25m (80 ft) typical, rarely 45m.
• Trunk: Up to 60cm diameter.
• Bark: Smooth gray on young trees, thickening and fissuring with age.
• Winter Buds: Reddish-brown, velvety.
• Fall Color: Golden-yellow—among the earliest to change (often by Labor Day).

Reproduction

Petalless flowers in dense panicles appear with spring leaves. Male and female flowers on separate trees (dioecious), wind-pollinated. Fruit is a straw-colored, winged samara (1–2.5 inches) in dense clusters, each containing a single seed with an elongated apical wing.

Primary Uses

Windbreaks

Extensively planted in prairie states/provinces for farmstead and field windbreaks—easy establishment, dense branching. Less effective long-term as lower branches drop with age.

Ornamental and Shade

Good form, disease resistance, and fast growth make it a landscaping staple.

Specialty Wood

Lighter than White Ash but same tonal quality—prized for guitar bodies (bright, sustaining sound, attractive grain).

Wildlife Value

Samaras feed birds, rodents, wild turkey. Twigs and foliage browse for deer.

Pest and Disease Concerns

• Carpenter worm and Green Ash borer cause serious damage.
• Older trees may develop rust and ash flower gall.
• Weedy conditions significantly reduce seedling growth rates.

Emerald Ash Borer Alert

Critical: The invasive Emerald Ash Borer (EAB) has devastated ash populations across North America. Before planting, check local EAB status and consider resistant species alternatives. Treatments exist for high-value trees but require ongoing commitment.

Planting Considerations

Select moist, well-drained sites for fastest growth. Space for mature spread. Monitor for pests. In EAB zones, diversify species selection.