Ontario Trees & Shrubs website

Blue Ash
Fraxinus quadrangulata

Other common names: Four-angled Ash

French names: FrÍne anguleux

Family: Olive Family (Oleaceae)

Group: Ashes

Distinctive features: Tree; Square twigs. Opposite branching but not as thick or obvious as other Ashes.

Similar species:
  •   White Ash (Fraxinus americana) - does not have square twigs.

  •   Black Ash (Fraxinus nigra) - does not have square twigs.

  •   Red Ash (Fraxinus pennsylvanica) - does not have square twigs.


Flowers: Spring

Leaves: Opposite/Whorled, Compound, Entire;  Opposite, compound.

Habitat: Fields and Open Areas

Books: Trees in Canada: 168   

Native/Non-native: Native

Status: Rare.

Notes: This tree only grows in a few locations in extreme SW Ontario, or other locations where it has been deliberately planted. Its distinctive feature is its 4-sided twigs.

Photographs: 69 photographs available, of which 5 are featured on this page. SCROLL DOWN FOR PHOTOGRAPHS.

Range Map is at the bottom of the page

Blue Ash (Fraxinus quadrangulata)

Sign at the University of Guelph Arboretum, Guelph, Ontario.

This tree is very rare in Ontario.

Blue Ash (Fraxinus quadrangulata)

This tree's distinctive feature is the square (4-sided) twigs.

Blue Ash (Fraxinus quadrangulata)

Another view of a 4-sided twig.

Blue Ash (Fraxinus quadrangulata)

Trunk and bark.

Blue Ash (Fraxinus quadrangulata)

The whole tree.


Range map for Blue Ash (Fraxinus quadrangulata)

PLEASE NOTE: A coloured Province or State means this species occurs somewhere in that Province/State.
The entire Province/State is coloured, regardless of where in that Province/State it occurs.

(Range map provided courtesy of the USDA website and is displayed here in accordance with their Policies)