Introduction

The species is a native of the American southwest, and is densely clothed in blue/grey leaves and becomes a narrow pyramid, perhaps reaching 50 to 70 feet tall. Exceptionally tolerant of hot, dry conditions, smooth barked Arizona cypress is ideal for use as a screen, hedge, or windbreak. The outer red/brown bark breaks off every year, revealing the fresh, new, bright red, smooth inner bark. Foliage of 'Carolina Safire' is one of the brightest blues you will ever see. Jump out of the way after planting this cultivar since it springs out of the ground, with young trees growing about 6 feet each year with irrigation.

General Information

Scientific name: Cupressus glabra

Pronunciation: koo-PRESS-us GLAY-bruh

Common name(s): Smooth barked Arizona cypress

Family: Cupressaceae

USDA hardiness zones: 7A through 9B (Fig. 2)

Origin: native to North America

Invasive potential: little invasive potential

Uses: screen; hedge; specimen; bonsai

Availability: somewhat available, may have to go out of the region to find the tree

Description

Height: 50 to 70 feet

Spread: 10 to 15 feet

Crown uniformity: symmetrical

Crown shape: pyramidal, oval

Crown density: dense

Growth rate: fast

Texture: fine

Foliage

Leaf arrangement: opposite/subopposite (Fig. 3)

Leaf type: simple

Leaf margin: entire

Leaf shape: scale-like

Leaf venation: none, or difficult to see

Leaf type and persistence: evergreen

Leaf blade length: less than 2 inches

Leaf color: blue or blue-green

Fall color: no color change

Fall characteristic: not showy

Flower

Flower color: unknown

Flower characteristics: not showy

Fruit

Fruit shape: round

Fruit length: less than .5 inch

Fruit covering: dry or hard

Fruit color: brown

Fruit characteristics: does not attract wildlife; not showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/bark/branches: branches don't droop; showy; typically one trunk; thorns

Pruning requirement: little required

Breakage: susceptible to breakage

Current year twig color: green

Current year twig thickness: thin

Wood specific gravity: unknown

Culture

Light requirement: full sun

Soil tolerances: clay; sand; loam; alkaline; acidic; well-drained

Drought tolerance: high

Aerosol salt tolerance: unknown

Other

Roots: not a problem

Winter interest: no

Outstanding tree: no

Ozone sensitivity: unknown

Verticillium wilt susceptibility: resistant

Pest resistance: sensitive to pests/diseases

Use and Management

Smooth barked Arizona cypress should be grown in full sun on well-drained, acid or alkaline soil. If grown with too much moisture or on a poorly-drained clay, a shallow root system will develop making the tree susceptible to wind damage. The species was once widely grown in the southeastern U.S. but may perform best in the drier parts of the southwest, including west Texas and Oklahoma.

Propagation is by cuttings.

Pests

No pests are of major concern.

Diseases

A stem canker has devastated large numbers of smooth barked Arizona cypress in various parts of the country.