A young ironwood tree, green leaves, summer, in a field with grass.
The Ironwood makes a great backyard tree as it is resistant to many disease and insect problems. It tends to blend in with other trees and is commonly labelled as inconspicuous. Other names: Hop-hornbeam, Bois dur, Bois de fer
Botanical Name: Ostrya virginiana
Nom Français: Ostryer de Virginie


Bloom colour: Maroon
Blooms: Spring - Zone 5
Pollinators: Birds | Mammals
Sun or Shade: Full Sun | Partial Sun | Shade
Plant Type: Tree
Height: Over 35 feet (10 meters)
It grows well in hardiness zones: 1 to 7

Ironwood is a slow-growing tree adapted to many situations, except on waterlogged soils where the similarly sized blue beech thrives. Though the Ironwood grows slowly, it does so easily in shade or full sun. Its fruit resembles hops and its seeds feed a variety of birds and small animals. It is virtually pest and disease free and is therefore relatively unproblematic.


Well-drained slopes and ridges, dry open woods.
Water requirement: Low water requirement.
Does best on neutral to acidic loam but tolerates a range from gravelly soils to poor drainage conditions.
Plant the ironwood seeds spaced 1 seed to every 1 to 1 1/2 inches. Push seeds firmly into the soil. Cover each of the seeds with approximately 1/4 of an inch of fine sand. Mist the surface of the soil in the planting flat to thoroughly dampen.


Handles sun and is also shade tolerant. Do not over-water.
Small tree with strong central stem. Slender, horizontal branches produce an irregular, rounded crown. Leaves oval shaped with sharp teeth.
Disease and pests are uncommon with the Ironwood.


Spread: As wide as tall.
Ironwoods should be pruned in autumn, after the leaves have fallen, or in early spring before the sap forms. Crowded, crossing and branches should be removed. Older trees should only need pruning every 3-4 years. The trunks of young trees should be protected from the winter sun.


Low to moderate pollution tolerance. Ironwood has the hardest wood of any native tree species, and is therefore not generally used for lumber. It has attractive fall colour and food for wildlife, and is recommended as an alternative to ash and Norway Maple trees.
Young trees prefer organic soils (manure or compost)

Styling and Use

Ironwood has relatively light litter production, so it would be a good candidate for near pool or pond planting.
Sugar Maple, American Beech, Yellow Birch, White Ash.


Trying to cut through an Ironwood stem resembles cutting through an iron pipe, as it shocks with a jolt when hit. It has greyish brown bark that splits and is said to look like strips of bacon when peeling.


Its wood used to be used to make tool handles, cogs and sleigh-runners.

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