Callitropsis nootkatensis

The Nootka cypress is a remarkable evergreen conifer. It belongs to the cypress family, known scientifically as Cupressaceae. This tree is native to the moist coastal mountains of northwestern North America. You can find it stretching from the Kenai Peninsula in Alaska down to the Klamath Mountains in northern California. It is a vital part of the Pacific Northwest ecosystem. This species is known by many common names. People call it the Alaska yellow cedar, yellow cypress, or Nootka cedar. The name "nootkatensis" refers to Nootka Sound on Vancouver Island. This location was named for the Nuu-chah-nulth First Nation.

Physically, the Nootka cypress is an impressive and large tree. It can grow quite tall with very large diameters. Its branches are often pendulous, which means they hang downward. This gives the tree a graceful, weeping appearance. The foliage grows in flat sprays of dark green scale-leaves. The bark changes as the tree ages. When the tree is young, the bark is thin, smooth, and purplish. As it grows older, the bark becomes gray and flaky. This tree is also very shade tolerant, though it grows slowly compared to other forest trees.

The reproduction of the Nootka cypress involves a specific process for its cones. These cones do not mature in a single year. Instead, they mature biannually, which means they take two years to fully develop. Each cone typically has four scales, though some may have six. These scales feature a pointed triangular bract, which is a small, leaf-like part. This feature distinguishes them from other related trees. Inside the cones are small, winged seeds. These wings allow the seeds to disperse, though they usually stay within a close range. Only a small percentage of these seeds are actually viable for growing new trees.

Scientists have spent nearly two centuries debating the correct classification of this tree. It was first described in 1824 as Cupressus nootkatensis. In 1841, researchers moved it to the genus Chamaecyparis. They did this because its foliage grows in flat sprays. However, the way its cones mature did not match that group. In 2000, genetic evidence suggested it should return to the Cupressus genus. Later, in 2002, it was placed in a new genus called Xanthocyparis. Finally, a 2021 molecular study confirmed the tree belongs in its own distinct genus, Callitropsis. This study found it is a sister genus to Hesperocyparis.

The Nootka cypress is famous for its incredible longevity. In the Caren Range of British Columbia, some specimens are extremely old. One specific tree was measured at 1,834 years old. Other specimens in that area may even be over 3,000 years old. This long life is aided by anti-fungal chemicals inside the tree. These chemicals protect it from decay and help it resist many insects. However, the tree can still suffer from heart rot. It also relies on heavy annual precipitation, often exceeding 2,000 mm, to thrive in its habitat.

Climate change poses a serious threat to these ancient trees. The Nootka cypress depends on deep, heavy snowpacks to survive cold winters. The snow acts like a blanket, insulating the shallow roots from Arctic temperatures. As the climate warms, snowpacks are becoming thinner and less persistent. This causes the roots to suffer from freeze damage. Researchers have observed this mortality over 7% of the species' range. This area covers about 10 degrees of latitude from southeast Alaska to British Columbia. Because of these risks, the U.S. Fish & Wildlife Service is reviewing its status. They are deciding if the tree should be labeled as threatened or endangered.

Humans have used the Nootka cypress for many purposes for a long time. Indigenous peoples of the Pacific Northwest used the wood and inner bark for many tools. The strong inner bark was perfect for making baskets and thread for clothing. The wood is highly valued for its durability and stability. It resists weather, insects, and contact with soil. Because it is hard and resists splintering, it is used for fine carpentry and shipbuilding. It is also an excellent firewood because it burns very hot. Even a tree that died 100 years ago can still be used as firewood. Today, it is used for everything from saunas to high-end interior finishes.