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Tree Browser

With these characteristics: None

Hophornbeam, Knowlton

Ostrya knowltonii

Betulaceae - Birch

Description

Leaves: Alternate; simple; oblong-ovate; 1" to 2" long; deciduous; 5-8 pairs of veins; sharply, doubly serrate margin; acuminate apex; thin; tough; dark green above; paler and somewhat hairy beneath; yellow fall color; petiole short, hairy.

Twigs/buds: Twigs slender; red-brown to dark brown.  No terminal bud; lateral buds pointed, scales with green bases and brown tips.

Flowers/fruit: Monoecious.  Fruit a small nutlet; enclosed in an oval, flattened, papery sac; sacs arranged in cone-like clusters, with the appearance of hops.

Bark: Thin; gray-brown; with small, shreddy plates.

Wood: Extremely hard, so often called "ironwood"; resembles hickory; diffuse-porous; little used.

General: Native to southeastern Utah, northern Arizona, southeastern New Mexico, and west Texas.  Slow growing, small tree.  Uncommon and found in canyons.  Shade tolerant.

Landscape Use: Essentially unknown in cultivated landscapes.  No cultivars available and may be difficult to find in any nursery, but could be grown from seed or dug from public land with a permit.  Might be a possibility for "native" landscapes.  Zones 6(5?)-9.

Characteristics

General

Family:
Betulaceae - Birch
Cultivar Availability:
No
Hardiness Zone:
6-9
Type:
Broadleaf
Utah Native:
Yes

Growth

Growth Rate:
Low
Mature Height:
Medium
Longevity:
High
Is Good Under Power Lines:
No
Crown Shape:
Irregular

Ornamental

Bark:
No
Fall Color:
No
Flowers:
Yes
Foliage:
Yes
Fruit:
Yes

Tolerence

Shade:
High
Salt:
Medium
Drought:
High
Poor Drainage:
Low
Alkalinity:
High
Transplanting:
Medium