Chapter 113 Ostrya virginiana

113.1 American hop hornbeam

Hop hornbeams turn an impressive golden orange in fall. Link to original image.

113.2 Soil: Moist Deciduous Mix

Ratio: 4 parts bark, 1 part grit

Add-ins: dolomitic limestone (~5 lbs/yd), Tree-Tone (15 lbs/yd)

pH: ~6.5 (slightly below neutral)

Moisture: Average

113.3 Light

Routine: prefers full sun to part shade

Summer: unknown, but given it is an understory tree, mid-day shade is likely needed.

113.4 Cultivation Notes

113.4.1 Potting & Root Pruning

Schedule: repot in early spring.

Notes: American hop hornbeam is difficult to transplant. The tree’s tap root can be cut in the nursery to give it a root structure to better fit a specific location. It can also be grown in containers or root-control bags.

113.4.1.1 Top & Branch Management

The trunk of an old, very large hop hornbeam. Link to original image.

Heavy pruning:

there are no published guidelines, but cut, burned, or injured trees commonly sprout from the stump. The proportion of stump sprouting increases with stump height. This suggests they have some dormant buds, but that they are widely scattered along the trunk.

Fine pruning: unknown.

Leaf pruning: unknown.

113.4.2 Feeding

Maturing hops-like fruits that give this species their common name. The leaves closely resemble those of true hornbeams (Carpinus). Link to original image.

I found no information. To start, I would assume they can be fed on the same schedule and protocol as hornbeams.

113.4.3 Pests & Problems

No serious insect or disease problems.

113.4.4 Winter Storage

Catkins provide winter interest. Link to original image.

Store in mulch outdoors. Try to place in a shaded area so buds do not break in a mid-winter warm spell. No other special precautions should be needed.

113.5 Propagation Notes

Uncommon in the nursery trade, but is available. Supposedly the seed may be sown in fall and allowed to stratify naturally, or stratified by storing in wet peat or sand over the winter then sowing them in spring. I have not tried it because I have not found a source for seed, either commercially or growing naturally.

113.6 Artistic & Styling Notes

113.7 Additional Information

113.7.1 Natural History

A member of the Betulaceae family. An understory specialist that is native to Eastern North America from Nova Scotia to Mexico. Hardy in USDA Zones 3 to 9. Trees can reach a height of 40 feet, with 30 foot spread. Like its cousin the American hornbeam, it sometimes is called ironwood because of its dense, hard wood. The fruits resemble hops, giving them their common name.

Hop hornbeam exhibits fast juvenile growth, but is described as a rather slow-growing tree overall. It tolerates a range of conditions, but absolutely does not tolerate salt. It will not do well in a seaside environment or anywhere with heavy road salt.

113.7.2 In Cultivation

It is grown as an ornamental plant and is sometimes used as a street tree.