Green Ash
Fraxinus pennsylvanica Marsh.
Frêne vert
Native Range:
The most widely distributed ash, found from Saskatchewan to Nova Scotia. It aggressively invades urban spaces and is frequently planted for landscaping purposes (Zones CA2, NA3).
Leaves:
5-9 (usually 7) leaflets on an almost hairless to hairy central stalk 15-20 cm long.
Leaflets are 10-15 cm long, oval, tapering to a point.
Toothed above the middle.
Upper surface is yellowish-green, paler and hairless to densely hairy beneath.
Turns yellowish-brown in autumn.
Stalks are almost hairless to hairy, with two narrow green wings.
Leaflets tend to fall one at a time in autumn.
Buds:
Terminal bud is 3-8 mm long, reddish-brown, hairy.
Uppermost pair of lateral buds is close to the terminal bud.
Leaf scars are semi-circular, sometimes with a slight notch in the upper surface.
Twigs:
Moderately stout, grayish-brown.
Varying from almost hairless to densely hairy, with hairs being less prominent in winter.
Flowers:
Pollen and seed flowers are on separate trees.
Stalks are almost hairless to densely hairy.
Fruits:
3-6 cm long, with the wing enclosing one-half or more of the seedcase, often notched at the tip.
Abundant seed crops occur almost every year.
Seeds may lie dormant in the litter for several years before germinating.
Bark:
Grayish-brown, often tinged with red on young branchlets.
Bark becomes broken into firm, narrow, irregular, slightly raised ridges that intersect and form a diamond-shaped pattern.
Size and Form:
Small to medium-sized trees, up to 25 m high, 60 cm in diameter, and can live up to 100 years.
Fast-growing.
Highly variable in form, from a small, shrubby tree with a leaning or twisted trunk to a slender tree with a straight trunk and rounded crown.
Habitat:
Commonly found on bottomlands.
Confined to river valleys in the Prairie provinces.
Often mixed with willow, silver maple, and eastern cottonwood.
Moderately shade-tolerant.
Can withstand prolonged flooding during the dormant season.
Notes:
Past taxonomic treatments of Fraxinus pennsylvanica distinguished at least three varieties (var. pennsylvanica "red ash", var. subintegerrima "green ash", and var. austini "northern red ash"). These varieties are no longer considered botanically valid, and "green ash" is now applied to the entire species.
Quick Recognition:
Leaflets usually 7, toothed above the middle, with winged stalks.
Uppermost pair of lateral buds close to the terminal bud.
Fruit wing encloses one-half or more of the seedcase.
Green Ash is a fascinating species with its wide distribution and adaptability!