In Bloom: Cryptomeria Japonica

Cryptomeria Japonica
Cryptomeria Japonica

.Jōmon Sugi, Cryptomeria japonica, has both historical and cultural significance in Japan.  Photo: Aleks Monk.

Cryptomeria japonica (Japanese Cedar) is a tall, stately, graceful conifer -- and the national tree of Japan. In fact, Cryptomeria are the oldest and largest living trees in Japan.

For me, it’s one of the most important trees in the Seattle Japanese Garden. Its historical and cultural role in Japan is very similar to that of Thuja plicata (Western Red Cedar) in the Pacific Northwest. Both were essential to the spiritual and material lives of the native peoples, and were used to construct buildings, furniture and household goods. The leaves of Japanese Cedar were burned as incense, and the straight trunks were used as pillars for temples and other buildings. In addition, Cryptomeria trees were often planted around shrines and tombs.

Cryptomeria trees are not true cedars, but rather members of the Cypress family (Cupressaceae). Their Japanese name is Sugi, which means “straight trunk.” Other common names are Japanese Redwood and Peacock Pine (for the feathery appearance of the foliage).

There’s only a single species (japonica) within the genus Cryptomeria, which is native to Japan. It does have distinct, geographically isolated varieties, and these have slightly different textures in their wood. Large numbers of Cryptomeria were planted in the mountains northwest of Kyoto, beginning in the prosperous Oei period (1394-1428), to supply timber posts for the construction of teahouses. The variety used was Kitayama Sugi. In addition to the single species, there are estimated to be more than 200 cultivars, most of them dwarf or semi-dwarf. Several of these are planted in the Seattle Japanese Garden, including in the Roji (teahouse garden).

Japanese Cedar is a fast-growing and long-lived tree, with a narrowly conical habit and horizontal branches, slightly pendulous at their tips. It may exceed 230 feet in its native Japan, but when grown in the U.S., 60 feet is a more typical height. Its bark is reddish-brown, and peels in vertical strips. Sharply-pointed, awl-shaped, green or blue-green needles are spirally arranged. Soft to the touch, the foliage may bronze in cold winters. The flower parts are concealed within the foliage, hence the botanical name Cryptomeria. The Greek krypt means “hide” and meris means “a part.” Small, light brown, rounded cones appear in autumn. The fragrant wood is lightweight but strong, waterproof and resistant to decay.

Although insect-resistant and long-lived, Cryptomeria does not tolerate air pollution, dust, sea breezes, or poor soils. It does best in full sun to dappled shade, and moist, fertile, well-drained soil.

Jōmon Sugi (縄文杉?) is the name of a large Japanese Cedar located on the island of Yakushima, a UNESCO World Heritage Site. It’s the oldest and largest of the Cryptomeria trees on the island, and is estimated to be at least 2,170 years old – and possibly over 7000 years old. The tree's name refers to the Jōmon period of Japan. Jōmon Sugi is 83 feet tall, with a trunk circumference of 54 feet. Its volume is approximately 10,000 cubic feet, making it the largest conifer in Japan. It’s been described as "a grim titan of a tree, rising from the spongy ground more like rock than timber, his vast muscular arms extended above the tangle of young cedars and camphor trees" (Remarkable Trees of the World (2002), by arborist Thomas Pakenham).

In the Seattle Japanese Garden, five tall Sugi, planted along the western fence line, form a backdrop to the cherry orchard and the Azumaya. Along with other tall conifers, both within and outside the garden, they serve as a fitting frame for the jewel that is our garden.

Corinne Kennedy is a trained guide for Seattle Japanese Garden and a contributor to the garden's blog.