Origin: Eastern North America (native in Ontario)
Hop-hornbeam is a small tree with a wide spreading conical crown.Read more about Tree, Bark, Twigs
Leaves are oval, with pointed tips, saw-toothed edges and short leaf stalks.Read more about Leaves
Male flowers are borne in catkins that hang in groups of 1 to 3. Female flowers are inconspicuous.Read more about Flowers
Fruits are inflated paper-like sacs, borne in hanging clusters.Read more about Fruit
Twigs are reddish-brown, with buds angled outwards. Buds are pointed, 3 - 4 mm (just over 1/10") long.
Leaves are oval, 7 - 12 cm (2 3/4" - 4 3/4") long, tapering to a pointed tip, with hairy undersides.
Male flowers are borne in catkins that hang in groups of 1 to 3, elongating to 5 cm (2") in Spring when mature.
Fruits are inflated green or brown paper-like sacs, 1 - 2 cm (about 1/2") long, borne in dangling clusters.
Hop-hornbeam is the only species of the genus Ostrya that is native to Canada. It is slow-growing and fairly long-lived, reaching 150 years.
Derivation of names
This species serves as an example of the confusion that can be caused by using common names. Ostrya virginiana is often called ironwood, a name that has been applied to dozens of tree species worldwide and several in North America, including the native Carpinus caroliniana (which is also called blue-beech, although it is not a beech). Carpinus caroliniana has also been referred to as American hornbeam, which is similar to other common names for Ostrya virginiana: American hophornbeam, eastern hophornbeam, and hop-hornbeam. Despite the similarities in names, the two species are quite different in appearance. For example, while Ostrya virginiana has shaggy, peeling bark, Carpinus caroliniana has very smooth bark with wavy ridges. These two species, and many others, bear the name Ironwood because of their hard, dense wood.
The meaning of the name hop-hornbeam is broken down in several ways: "hop" refers to the similarity of the fruit clusters to hops, an ingredient in beer-making; "horn" refers to the hardness of the wood; and "beam" comes from an archaic English word for tree.
The genus name, Ostrya, may come from the Greek work ostrua, which means a tree with very hard wood, or ostruos, meaning scale, in reference to the scaly catkins. The species name, virginiana, means "from Virginia."
Hop-hornbeam is too small and its wood is too hard and dense for most commercial uses. However, it has been used to manufacture tool handles.
The seeds, buds and catkins serve as a food source for songbirds, squirrels, pheasants, and grouse.
Hop-hornbeam is very similar to two other species of Ostrya, Ostrya carpinifolia (European hop-hornbeam) and Ostrya japonica (Japanese hop-hornbeam). The differences are extremely minor; distinction poses a challenge even for some seasoned tree experts.
Hop-hornbeam's place in Toronto's urban forest
Landscape value and potential for home planting
As a fairly small tree, hop-hornbeam is suitable for planting in smaller sites. Its unusual fruit and distinctive bark make it a visually interesting addition to the urban landscape. However, it is slow-growing and it has not been a popular urban tree in the past. Due to its very large range, which extends into the southern US, hop-hornbeam is naturally associated with a wide range of broadleaf trees and such conifers as pines, firs, and hemlock.
In its native habitat, hop-hornbeam is an understory tree, so it is tolerant of some shade. It should be planted in moist, slightly acidic soil.
Pests and diseases: Hop-hornbeam is relatively free of insect pests and diseases. However, it may succumb to trunk or butt rots.
Links to maps at Canadian Tree Tours: