Tree of the Month, October 2022

Eastern Hop Hornbeam, aka Hop Hornbeam, Ironwood

Ostrya virginiana

by Martin (Mort) Schmidt

for Simply Living

Eastern Hop Hornbeam is often overlooked today, but it was once an essential wood due to its considerable hardness. It’s often confused with two other understory trees, American Hornbeam – Ohio’s other “Ironwood”, and Common Hoptree, which also has the word “hop” in its name. American Hornbeam and Common Hoptree were Simply Living’s June 2022 and August 2022 Trees of the Month, respectively. 

Hop Hornbeam leaves are nearly identical to American Hornbeam leaves. The leaves are alternately arranged and simple, i.e., the leaves and branches are not attached directly across from one another and they’re attached directly to the permanent part of the tree rather than sharing a stem with other leaflets. The leaves are elliptical and pointed, and have double saw teeth and pinnate veining. Pinnately-veined leaves are feather-like, and have a single primary vein with secondary veins attached to it at different points. Palmately-veined leaves are hand-like, with multiple veins attached at the stem. 

Hop Hornbeams are somewhat larger than their cousins, the American Hornbeams, and have a mature height of approximately 50 feet and a trunk diameter of 12 inches. Ohio’s Champion Hop Hornbeam in Trumbull County has a height of 67 feet and a trunk diameter of 24 inches. While the leaves are not especially distinctive, Hop Hornbeam bark is instantly recognizable, with fine vertical fissures reminiscent of cat scratches. The other Hornbeam, American Hornbeam, aka Muscle Wood, has smooth bark on a sinewy trunk. Hop Hornbeam fruits look like the hops used in beer, whereas Common Hoptree fruits are wafers which taste like hops, and were once used to flavor beer. 

Hop Hornbeam flowers consist of yellow-green catkins. Because they emerge before most insects, they’re wind-pollinated and don’t need to attract insects with showy petals or sweet fragrance. It’s often said that “Fortune favors the courageous”, but in pollination, fortune favors the copious. Each Hop Hornbeam catkin can hold several million grains of pollen. Because pollen grains have perhaps a one-in-a-milllion chance of landing on a female flower, male flowers evolved to produce millions of pollen grains. 

As the common name “Ironwood” suggests, the hornbeams have unusually hard wood; in fact, the name “hornbeam” comes from a Germanic term meaning hard wood. But notice that “Ironwood” is a name used for over 100 of the world’s woods, most of which are harder than Ohio’s “Ironwoods”, Hop Hornbeam and American Hornbeam. According to the WoodDatabase.com, Hop Hornbeam has a Janka hardness of 1,860 lbf and a density of 0.63 g/cc, compared to the medians of 1,050 lbf and 0.57 g/cc on my table of 86 Ohio trees. But wood hardness is a measure of wood’s resistance to crushing, and while most of the world’s “Ironwoods” and even some of Ohio’s trees are harder and heavier than Hop Hornbeam, the latter is especially tough, i.e., resistant to splitting in use. The combined traits of hardness, toughness, durability (rot resistance) and fine grain led to its use as a wedge for splitting logs of other woods, for wooden-plane bodies, tool handles, mallet heads, wheel spokes and hubs, and fence posts. Hop Hornbeam was also useful for making levers – pry bars – and was occasionally called “Lever Wood”. 

Like many people, I tend to think of harder woods, such as oak, as superior to softer woods, like Tuliptree (aka “Yellow Poplar”, although it’s not a poplar). But because the early settlers and Natives worked wood with hand tools, they used woods that were hard enough to hold up, but no harder. Consequently, it seems odd that they carved cups and bowls from Hop Hornbeam, when hardness offered little or no advantage. But they got around the hardness problem, at least in part, by carving Hop Hornbeam “green”, before it dried. Hop Hornbeam’s superior split resistance kept it from cracking as it dried, and its fine grain and neutral flavor kept it from flavoring food. 

Finally, like most dense woods, Hop Hornbeam burns hot and makes excellent firewood. But Hop Hornbeam’s small size and relative scarcity limits its use commercially, and its sale today is limited to specialty markets. 

Wildlife eat Hop Hornbeam seeds, but humans apparently consumed Hop Hornbeam mostly as medicine. The North American Ethnobotany Database lists the following medicinal uses of Hop Hornbeam by Native Americans: 

• Cherokee: Infusion of bark taken to build up blood
• Cherokee: Infusion of bark held in mouth for toothache
• Chippewa: Decoction of heartwood used as herbal steam for rheumatism
• Chippewa: Liquid made from wood taken as a cough syrup
• Chippewa: Decoction of wood taken for kidney trouble
• Chippewa: Infusion of inner wood taken for lung hemorrhage
• Delaware: Compound containing root used as a tonic
• Iroquois: Decoction of heart chips taken for coughs
• Iroquois: Decoction of bark taken for tuberculosis 
• Potawatomi: Infusion of bark used for diarrhea 

Be on the watch for this interesting tree with hop-like fruits and cat-scratch bark.