Herbs & Plants

Calocedrus decurrens

Botanical Name: Calocedrus decurrens
Family: Cupressaceae
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Genus: Calocedrus
Species: C. decurrens

Synonyms: Libocedrus decurrens Torr,Heyderia decurrens. Libocedrus decurrens. Thuja gigantea.

Common Names: Incense cedar and California incense-cedar

Habitat: Calocedrus decurrens is native to South-western N. America – Oregon to California. It is found on a variety of soils, usually on western slopes at an altitude of 700 – 2500 metres. The best specimens are found on deep well-drained slightly acidic sandy loam soils.

Calocedrus decurrens is a large tree, typically reaching heights of 30–40 meters (100–130 ft) and a trunk diameter of up to 1.2 m (3 ft 11 in). The largest known tree, located in Klamath National Forest, Siskiyou County, California, is 47.98 m (157 ft 5 in) tall with a 12-meter (39-foot-4-inch) circumference trunk and a 17.5-meter (57+1?2 ft) spread.[8] Specimens form a broad conic crown of spreading branches. The bark is orange-brown weathering grayish, smooth at first, becoming fissured and exfoliating in long strips on the lower trunk on old trees. Specimens can live to over 500 years old.

The foliage is produced in flattened sprays with scale-like leaves 2–15 millimeters (3?32–19?32 in) long; they are arranged in opposite decussate pairs, with the successive pairs closely then distantly spaced, so forming apparent whorls of four; the facial pairs are flat, with the lateral pairs folded over their bases. The leaves are bright green on both sides of the shoots, with only inconspicuous stomata. The foliage, when crushed, gives off an aroma somewhat akin to shoe-polish.

The seed cones are 20–35 mm (3?4–1+3?8 in) long, pale green to yellow, with four (rarely six) scales arranged in opposite decussate pairs; the outer pair of scales each bears two winged seeds, the inner pair(s) usually being sterile and fused together in a flat plate. The cones turn orange to yellow-brown when mature about 8 months after pollination. The pollen cones are 6–8 mm (1?4–5?16 in) long.


Calocedrus decurrens succeeds in full sun in a moist well-drained soil that is neutral to acid, though it will also survive on dry alkaline soils. Plants are shade tolerant when young. It grows best in a position that is sheltered from strong winds. Trees are slow growing but long-lived in the wild, with specimens up to 1000 years old recorded. They grow slowly in Britain, but they are perfectly hardy. Young trees can grow 60cm in a year but they seldom average more than 30cm. Growth virtually stops once the tree reaches 25 metres tall. All parts of the plant are strongly aromatic. This species is strongly resistant to honey fungus. The tree exhibits very different crown habits dependant upon the area in which it is being grown. At one time these different habits were considered to be different sub-species, but it is recognised now that it is only climatic forces that cause the differences. Special Features: North American native, Fragrant foliage, Inconspicuous flowers or blooms.

Through Seed – sow early spring in a greenhouse. When large enough to handle, prick the seedlings out into individual pots and grow them on in light shade in a greenhouse or cold frame for their first winter. Plant them out in late spring or early summer, after the last expected frosts and consider giving them some protection from the cold for their first winter outdoors. Cuttings of the current season’s growth, taken in mid autumn, in a light sandy soil in a cold frame.

Edible Uses:
The dense leaflets have been used as a flavouring and protection when leaching acorns.A Northern California tribe used branchlets to filter out sand from water when leaching toxins from acorn meal; foliage also served as a flavoring.

Medicinal Uses:
A decoction of the leaves has been used to treat stomach troubles. Steam from an infusion of the leaves has been inhaled in the treatment of colds.
Indigenous peoples of California use the plant in traditional medicine.

Other Uses:
The boughs and twigs have been used to make brooms. The roots have been used as overlay twine warps and overlay twine weft bases in making baskets. The bark has been made into baskets. Wood – soft, light, close grained, very durable in the soil though it is often damaged by dry rot. It has a powerful, incense-like fragrance and is used for making shingles, lathes, fencing, pencils, construction etc. Mature trees are often infected by dry rot, so they are not considered to be a major timber species.

The wood is soft and light, and has a pleasant odor and is generally resistant to rot. It has been used for external house siding, interior paneling, and to make moth-resistant hope chests. It was once the primary material for wooden pencils, because it is soft and tends to sharpen easily without forming splinters.

The tree is also grown in gardens and parks in cool summer climates, including the Pacific Northwest in the Northwestern United States and British Columbia, eastern Great Britain and continental Northern Europe. In these areas it can develop an especially narrow columnar crown, an unexplained consequence of the cooler climatic conditions that is rare in trees within its warm summer natural range in the California Floristic Province. Other cultivated species from the family Cupressaceae can have similar crown forms.The natives uses it in basket making, hunting bows, building materials, and to produce fire by friction.

Disclaimer : The information presented herein is intended for educational purposes only. Individual results may vary, and before using any supplement, it is always advisable to consult with your own health care provider.


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