Ostrya carpinifolia
Common Name: hop hornbeam 
Type: Tree
Family: Betulaceae
Native Range: Western Asia, Europe
Zone: 5 to 9
Height: 40.00 to 50.00 feet
Spread: 30.00 to 40.00 feet
Bloom Time: April
Bloom Description: Yellowish-green
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Shade Tree, Street Tree
Flower: Insignificant
Fruit: Showy
Tolerate: Rabbit, Deer

Culture

Best grown in moist, acidic, humusy, organically rich, well-drained soils in full sun. Tolerates part shade, but with somewhat diminished flowering and fall color. Intolerant of drought. Intolerant of urban pollution. Best sited in locations protected from strong winds.

Noteworthy Characteristics

Ostrya carpinifolia, commonly called European hop hornbeam, is a small to medium deciduous tree that typically matures to 40-50' (less frequently to 70') tall featuring an upright pyramidal shape when young which broadens with age as side-branching develops and the crown rounds. This tree is native to southern Europe, southwestern Asia and the Caucasus. Alternate, glossy, oval, dark green leaves (to 5" long) have pointed tips, rounded bases and doubly serrated edges. Leaves turn yellow in fall. Yellowish-green catkins appear in spring (male to 5" long and female to 2" long). Each female catkin gives way to a pendulous seed cluster (2-3" long) containing 6 to 20 small nutlets. Each nutlet is enclosed in a bladder-like involucre bract. The seed clusters are reminiscent of the hops (Humulus) used to make beer. Nutlets mature in summer. Scaly gray bark. This tree is very similar to Ostrya virginiana of eastern North America except it has more veins per leaf (15-20 veins as opposed to 12-15), rounded instead of cordate leaf bases, and ovoid nutlets.

Genus name comes from the Greek name ostrys used for this tree.

Specific epithet comes from the Latin words carpinus meaning hornbeam and folius meaning leaf in reference to the hornbeam-like foliage.

Common name of hop hornbeam is in reference to the similarity of this tree to hornbeam and its hop-like clusters of drooping nuts.

Problems

No serious insect or disease problems. Leaf spot and twig blight infrequently occur.

Uses

Specimen tree with multi-season interest for lawns, patios, shade gardens or open woodland areas.