Chamaecyparis lawsoniana

Common Name: Lawson's cypress 
Type: Needled evergreen
Family: Cupressaceae
Native Range: Western North America
Zone: 5 to 8
Height: 110.00 to 175.00 feet
Spread: 30.00 to 60.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Leaf: Evergreen
Other: Winter Interest

Culture

Easily grown in average, moist but well-drained soils in full sun to part shade. Avoid wet, poorly-drained soils. Shelter from strong winds. Pruning is rarely needed.

Noteworthy Characteristics

Chamaecyparis lawsoniana, commonly known as Lawson's cypress, is a tall, narrow-pyramidal, scaly-leaved, evergreen conifer with short spreading branches and flattened twigs. It is the tallest member of the cypress family. In its native habitat, it will grow over time to 110-175' (sometimes to 200' or more) tall and to 4-6' in diameter, but usually much shorter (to 40-60' tall) in cultivation. This tree has a very small native range; primarily being found on seaward slopes in a coastal belt along Pacific Coast mountain ranges from Coos Bay in southwestern Oregon to the Klamath River in northwestern California, with isolated additional populations in northern California near the Trinity Mountains and Mount Shasta. It sometimes grows in pure stands, but also is found growing with western red cedar, grand fir, western hemlock and Sikta spruce. Tiny, scale-like, bright green to blue green leaves (to 1/16" long) with silver marks beneath are pressed against the branchlets. Spherical female cones (1/4 to 3/8" diameter) are green maturing to brown. Oblong male cones are smaller, reddish-brown and oblong. Thick, silvery-brown to reddish-brown bark is furrowed and ridged. Wood is hard and durable. Although the supply is limited, lumber from this tree is in great demand. Charles Lawson (1794-1873) was a Scottish nurseryman.

Another common name for this tree is Port Orford cedar (unfortunately misleading because this is not a cedar) in recognition of the discovery of this tree in 1854 near the area now occupied by the town of Port Orford, Oregon.

Genus name comes from Greek chamai meaning dwarf or to the ground and kyparissos meaning cypress tree.

Problems

Phytophthora lateralis is a fungus which has spread through the native range of this tree at a rapid rate. It causes an often-fatal root rot disease which poses a significant threat to the survival of the species.

Garden Uses

Huge tree that is infrequently grown in landscapes. A large number of compact to dwarf cultivars of this species are available in commerce for ornamental plantings.