Chamaecyparis lawsoniana

Port Orford-cedar, Lawson Cypress
 

Mature Size, Growth, Longevity

Grows 40-60' tall in the landscape, but grows to 140-180' tall in the wild. National champion is 242' tall and 35' wide in Oregon. Develops a stout, buttressed trunk. Upright branches droop at the tip, with flattened foliage at the tips. Graceful habit. Medium growth rate.

Native Range

U.S. Native — Sometimes occurs on high, dry, sandy ridges, but does best where there is an adequate supply of soil moisture. Native to SW Oregon and parts of NW California. Introduced into cultivation in 1854.

Flower and Fruit Details

Flowers are monoecious. Male flowers are pink to reddish. Female flowers are bluish in color. Fruits are abundant, round, 1/3", bluish-green, then reddish-brown, and covered with a waxy bloom, 8-scaled.

Leaf and Bark Features

Evergreen: Branchlets are frond-like, flattened foliage, glaucous green to dark green on top, composed mostly of overlapping scales, each 1/20" to 1/12" long, arranged in opposite pairs, with faint white streaks or "Y's" on undersides, sometimes glandular pitted. Foliage is soft, not stickery like some junipers would be, since the foliage is made up of scales, not awls. Bark is fibrous, silvery brown to reddish-brown, deeply ridged and furrowed. Bark gets up to 6-10" thick on old trees.

Culture and Care

Prefers moist, well-drained soil. Full sun to part shade. Does best in acid soils where wind protection is provided. Not drought tolerant. Pruning is rarely needed. Zones 5-7. Phytophthora root rot may be a problem, especially in low, wet, poorly-drained soils. May develop witches' broom and a few minor insect pests.

Strengths, Weaknesses, Other Facts

4-season interest: Spring, summer, fall & winter. Named after Charles Lawson, 1794-1873, a Scottish nurseryman. This is the tallest member of the Cypress family. Conservation status is listed as "near-threatened" on the IUCN Red List.

Suggested Uses

Makes a good specimen tree with an interesting growth habit. Good for larger properties.

Taxa and Plants of this Species at BCA

The following taxa are (or were) represented in the collections at Boone County Arboretum. Additional taxa may be available in the trade that are not included here.

  • Chamaecyparis lawsoniana 'Yvonne' // Yvonne Port Orford-cedar, Lawson Cypress
    Tree. Foliage is golden-yellow tipped for fall and winter, while basal (inner) foliage on each branch stays green. Grown on Guardian Rootstock, developed by Oregon State University, providing good disease resistance to the otherwise fatal Phytophthora root rot. Good when used as an informal hedge or in a shrub border, or just as an accent plant for its bright yellow foliage color, which of the extends quite a ways down the stem. Needs full sun. Mulch and water regularly to avoid drought stress. Full sun location will create a brighter yellow fall foliage color. Moderate growth rate. Average landscape size is 10-20' tall and 6-12' wide. Zone 6-9.
    BT001458