The towering giants of California, often broadly referred to as “redwoods,” frequently cause confusion due to their similar appearances and immense stature. While both are impressive, they represent two distinct species with unique characteristics and habitats. Understanding these differences clarifies the identities of these iconic trees.
Understanding the Terminology
The term “redwood” refers to the Coast Redwood (Sequoia sempervirens). This species is the tallest living tree on Earth. The “sequoia” denotes the Giant Sequoia (Sequoiadendron giganteum), which holds the record for the largest tree by volume. Both belong to the cypress family (Cupressaceae) and the subfamily Sequoioideae, but they are different genera and species.
Key Physical Distinctions
Coast Redwoods are the world’s tallest trees, often exceeding 300 feet, with some reaching over 380 feet. Their trunks are slender and can be up to 29 feet in diameter at breast height. The bark of a Coast Redwood is reddish-brown, thick, fibrous, and deeply furrowed, providing protection from fire. Their leaves are flat, needle-like, and arranged in two rows, forming feathery sprays. Small, oblong seed cones, about 0.5 to 1.25 inches long, are produced.
Giant Sequoias are the most massive trees by volume globally. They grow to heights of 164 to 279 feet, with some reaching 310 feet. Their trunks are exceptionally broad, with diameters ranging from 20 to 26 feet, and the largest known can exceed 28 feet at the base. The bark is a bright reddish-brown, fibrous, and very thick, sometimes up to 3 feet, offering significant fire resistance. Giant Sequoia leaves are small, awl-shaped, and scale-like, resembling those of junipers, and are arranged spirally on the shoots. Their cones are larger than those of the Coast Redwood, 1.5 to 3 inches long.
Geographic Homes and Habitats
Coast Redwoods thrive in a narrow band along the Pacific Coast, stretching from southern Oregon to central California. This habitat has a cool, moist maritime climate, with frequent summer fog playing a role in their survival. The fog provides essential moisture during the dry summer months and reduces water loss from the trees. These trees are found at lower elevations, from sea level up to 3,000 feet.
Giant Sequoias have a more restricted and isolated natural range, growing exclusively on the western slopes of the Sierra Nevada mountains in central California. Their groves are scattered across a 260-mile belt at higher elevations, between 4,000 and 8,000 feet. Unlike Coast Redwoods, Giant Sequoias rely on snowmelt for much of their water supply, thriving in a humid climate with dry summers and snowy winters. The distinct geographic ranges mean these two species do not naturally overlap.
Conservation and Importance
Both Coast Redwoods and Giant Sequoias are symbols of California’s natural heritage and are subject to conservation efforts. Coast Redwoods have faced extensive logging, with only about 5% of the original old-growth forests remaining, much of which is now protected in national and state parks. The species is listed as endangered by the International Union for Conservation of Nature (IUCN), facing threats from habitat fragmentation, climate change, and increased fire frequency.
Giant Sequoias are also listed as endangered by the IUCN, with fewer than 80,000 mature trees remaining in their native California. Historically, logging impacted many groves, and modern challenges include prolonged drought and severe wildfires, which have killed a significant percentage of mature trees in recent years. Conservation efforts focus on protecting existing groves, managing fire, and ensuring the long-term survival of these ancient and massive trees.