Many people use “sequoia” and “redwood” interchangeably, leading to confusion. While related, Coast Redwoods and Giant Sequoias are distinct species with unique characteristics. Understanding their scientific identities and specific traits helps clarify their differences and appreciate each one.
Understanding Their Scientific Identity
Both Coast Redwoods and Giant Sequoias are members of the redwood subfamily, Sequoioideae, part of the larger cypress family, Cupressaceae. This subfamily includes some of the largest and tallest trees globally. The Coast Redwood is scientifically known as Sequoia sempervirens, the sole living species within the genus Sequoia. Its name “sempervirens” means “evergreen,” reflecting its year-round foliage.
The Giant Sequoia (Sequoiadendron giganteum) is the only living species in the genus Sequoiadendron. The Sequoioideae subfamily also includes Metasequoia, known as the Dawn Redwood, native to China and deciduous. The prominent species in California are the Coast Redwood and the Giant Sequoia.
Key Differences
Coast Redwoods (Sequoia sempervirens) and Giant Sequoias (Sequoiadendron giganteum) exhibit several distinguishing physical characteristics. Coast Redwood bark is typically reddish-brown, thick, and fibrous, often deeply furrowed. Giant Sequoias also have thick bark, up to 60 centimeters (2 feet) thick at the base, but it tends to be a brighter, lighter reddish-brown and feels spongy and soft.
Their foliage differs noticeably; Coast Redwood needles are flattened, resemble those of a yew tree, and are arranged in two rows along the twig. Giant Sequoia leaves are more awl-shaped, shorter, and scaled, pressed close against the branches, giving them a compact, spiky appearance. The cones produced by these trees also vary in size. Coast Redwood cones are relatively small, about 1-3 centimeters (0.5-1 inch) long, while Giant Sequoia cones are larger, typically 5-8 centimeters (2-3 inches) long, and take two seasons to mature.
Coast Redwoods are known as the world’s tallest trees, with many exceeding 91 meters (300 feet) in height, and some reaching over 110 meters (361 feet). Their trunks are massive but generally more slender and columnar. Giant Sequoias, while not as tall, are the world’s most massive trees by volume, possessing immense girths and broader, more conical forms. The largest known living single-stem tree by volume is a Giant Sequoia.
Shared Characteristics
Despite their differences, Coast Redwoods and Giant Sequoias share several remarkable characteristics. Both species are renowned for their immense size, ranking among the largest and tallest trees on Earth. They are also long-lived, with individuals capable of living for thousands of years. The oldest known Giant Sequoia is over 3,200 years old, while Coast Redwoods can live for more than 2,200 years.
Their thick, fibrous bark provides a natural defense against wildfires, allowing them to often survive fires that would destroy other tree species. This fire resistance is a crucial adaptation in their native ecosystems. Both species exhibit strong resilience to pests and diseases, which contributes to their longevity. These trees play significant ecological roles, forming unique forest ecosystems that support diverse plant and animal life.
Geographic Distribution
The natural habitats of Coast Redwoods and Giant Sequoias are distinct, reflecting their differing environmental preferences. Coast Redwoods (Sequoia sempervirens) are primarily found in a narrow coastal strip of California, extending from southern Oregon to Monterey County. This range is typically within 8 to 56 kilometers (5 to 35 miles) of the Pacific Ocean, where they thrive in moist, foggy coastal conditions. The fog provides essential moisture during drier periods, preventing desiccation.
Giant Sequoias (Sequoiadendron giganteum) grow exclusively on the western slopes of the Sierra Nevada mountains in California. Their distribution is limited to about 75 disjunct groves, spanning from Placer County south to Tulare County. These trees are found at higher elevations, generally ranging from 1,400 to 2,000 meters (4,590 to 6,560 feet) in the northern part of their range and up to 2,150 meters (7,050 feet) in the south. This mountainous, inland habitat experiences different climatic conditions, including more snow and less coastal fog, which influences their growth patterns and adaptations.