and Deciduous Forest Trees

of Southern Ontario

Red Ash
Fraxinus Pennsylvanica

Location in Ontario:
Red Ash grows throughout the Deciduous Forest Region and northward.

Large Red Ash, Long Point, Norfolk County
Genus Fraxinus: Ash trees have opposite compound leaves with 5-11 leaflets. Ash can be monoecious or  dioecious depending on the species. Seeds are contained in a single winged samara (a seed in a papery tissue). Ash wood is valued for its strength and hardness. Black, Red and White Ash grow in Ontario, as well as two Carolinian species, Pumpkin Ash and Blue Ash.

TREE FACT: Ash and Hickory are similar, both with compound leaves. Ash leaves are opposite while Hickory leaves are alternate.
Emerald Ash Borer is an invasive beetle accidently brought to North America from Asia in shipping boxes in 2002. It has quickly spread killing millions of Ash trees. Blue Ash has shown some immunity. There is a pesticide that can be used to control Emerald Ash Borer, but it is very expensive, and must be administered every two years. Unfortunately, many non-infected Ash trees have been cut down as a preventative measure. This eliminates trees that may have had a natural immunity. For more information and encouraging news about saving Ash trees:
Save the Ash Tree Coalition

The tell-tale tracks of the Emerald Ash Borer

Habitat: Red Ash is found along sandy shores, river valleys and flood plains.

Landscape Use:
Red Ash makes a good lawn tree with its nice form and leaves. It is risky to plant, however, due to Emerald Ash Borer.

Red Ash, Norfolk County.

Leaves: Red Ash has opposite, compound leaves, with 5 to 9 leaflets.

Red Ash leaves, University of Guelph Arboretum

??Red Ash or White Ash?? They are hard to tell apart, except in fall when Red Ash has yellow leaves, and White Ash has reddish-purple leaves. White Ash leaves have whitish undersides, and upper branches that are smooth. The leaf scar is "C" shaped. Red Ash  leaves are densely hairy beneath, and have a "D" shaped leaf scar. The upper branches appear rough.

FALL COLOUR WATCH: Yellow to gold

Flowers: Red Ash is dioecious (male and female flowers on different trees). Flowers are small and darkly coloured, and appear in early spring.

Red Ash flowers

Fruit: Seeds (samara) form in summer, and fall off in autumn. Some seeds persist into winter. Seed production occurs after 10 years of growth and seed crops usually occur every year.

Bark: The bark is grayish-brown sometimes tinged with red and has a diamond pattern.

Size: Red Ash is a shrubby to medium sized tree, up to 25 metres tall, and living 100 to 150 years.

TREE FACT: The name "Green Ash" is used for Red Ash trees which have hairless leaves, uncommon in Southern Ontario.

Wood: Ash wood is hard and heavy. It is used for flooring and furniture, as well as hockey sticks, tennis rackets and tool handles.
Specific Gravity:
Janka Hardness: 1200 lb
Wood Comparison Chart

Genetics: Red Ash is diploid. It does not form hybrids, except with Velvet Ash, which does not occur in Canada, but is found in the United States.

TREE FACT: There is some evidence that Pumpkin Ash, a hexaploid, resulted from a cross between a diploid Red Ash and a tetraploid White Ash.

Red Ash, University of Guelph Arboretum