The terms “redwood” and “sequoia” are often used interchangeably, causing confusion. While related, these terms describe distinct species within a larger botanical family. This article clarifies their scientific relationships and unique characteristics.
The Redwood Family Tree
The term “redwood” broadly refers to coniferous trees with reddish wood, belonging to the subfamily Sequoioideae within the cypress family (Cupressaceae). The “sequoia” designation points to a specific genus within this subfamily. The Sequoioideae subfamily includes three distinct genera, each with a single living species: the Coast Redwood (Sequoia sempervirens), the Giant Sequoia (Sequoiadendron giganteum), and the Dawn Redwood (Metasequoia glyptostroboides). These species represent an ancient lineage, with fossil records dating back to the time of dinosaurs.
Coast Redwoods vs. Giant Sequoias
Coast Redwoods (Sequoia sempervirens) and Giant Sequoias (Sequoiadendron giganteum) are two well-known “redwood” species native to California. They differ in preferred habitats and physical attributes. Coast Redwoods thrive in the moist, foggy coastal belt of northern California and southern Oregon, often within 20 miles of the Pacific Ocean. Giant Sequoias, however, are found in scattered groves on the western slopes of California’s Sierra Nevada mountains, typically at higher elevations between 4,000 and 8,000 feet.
Coast Redwoods have a slender trunk with a conical crown and branches that may slightly droop. Their bark is thick, soft, and fibrous, displaying a bright red-brown color. The needles are flat, about 0.6 to 1 inch long, and arranged in two ranks along the stem. Giant Sequoias have an immense, columnar trunk that maintains a large diameter to greater heights. Their bark is also reddish-brown, fibrous, and can be up to 3 feet thick, providing significant fire protection. Their leaves are blue-green, awl-shaped, and scale-like, measuring about 0.16 to 0.24 inches long, spirally arranged on the shoots.
Coast Redwoods hold the record for the world’s tallest trees. The tallest known individual, Hyperion, reaches approximately 380 feet in height. Giant Sequoias, while not as tall, are the most massive trees by volume. The General Sherman Tree is the largest by volume, measuring over 52,508 cubic feet. Both species are long-lived; Coast Redwoods can live for 1,200 to 2,200 years, while Giant Sequoias can reach ages of 3,200 years.
Beyond the Giants: The Dawn Redwood
The Dawn Redwood (Metasequoia glyptostroboides) is the third species in the redwood subfamily. This tree has a unique history, once believed extinct and known only through fossil records. In 1941, a Chinese forester rediscovered living specimens in a remote area of China.
Unlike its evergreen Californian relatives, the Dawn Redwood is deciduous, shedding its needles in autumn, which turn reddish-brown before falling. Dawn Redwoods are fast-growing trees, reaching heights of up to 100 to 115 feet and trunk diameters exceeding 3 feet in cultivation. While still large trees, they do not attain the immense sizes of Coast Redwoods or Giant Sequoias. Their bark is vertically fissured and tends to exfoliate in ribbon-like strips. Its rediscovery and global distribution of seeds in the late 1940s ensured its survival, making it a “living fossil” now grown in many botanical gardens worldwide.