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Western Hop-hornbeam, Knowlton's Hophornbeam, Wooly Hornbeam, Ironwood

Ostryaknowltonii

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Family

Betulaceae (beh-tyoo-LAY-see-ee)

Info

Genus

Ostrya (OSS-tree-uh)

Info

Species

knowltonii (nohl-TOH-nee-eye)

Info

Synonym

Sun Exposure

Sun to Partial Shade

Foliage

Grown for foliage

Deciduous

Height

20-30 ft. (6-9 m)

30-40 ft. (9-12 m)

Spacing

20-30 ft. (6-9 m)

Hardiness

USDA Zone 6a: to -23.3 °C (-10 °F)

USDA Zone 6b: to -20.5 °C (-5 °F)

USDA Zone 7a: to -17.7 °C (0 °F)

USDA Zone 7b: to -14.9 °C (5 °F)

USDA Zone 8a: to -12.2 °C (10 °F)

USDA Zone 8b: to -9.4 °C (15 °F)

USDA Zone 9a: to -6.6 °C (20 °F)

USDA Zone 9b: to -3.8 °C (25 °F)

USDA Zone 10a: to -1.1 °C (30 °F)

USDA Zone 10b: to 1.7 °C (35 °F)

Danger

Handling plant may cause skin irritation or allergic reaction

Bloom Color

Red

Brown/Bronze

Bloom Time

Mid Spring

Other Details

Gardener's Notes:

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positive

neutrals

negative

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Rickwebb

Downingtown, PA | June 2016 | neutral

This species is a smaller tree than the Eastern Hophornbeam and is more likely to have several trunks. It has smaller leaves of no more t...Read More

Terry

Murfreesboro, TN (Zone 7a) | August 2003 | neutral

Also known as "Ironwood" because of their extremely dense, hard wood, the Hophornbeam seedpods resemble hops, alluded to by their common name.

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Western Hop-hornbeam, Knowlton's Hophornbeam, Wooly Hornbeam, Ironwood

Ostryaknowltonii

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