Giant sequoias (Sequoiadendron gigantea) and coast redwood trees (Sequoia sempervirens) both belong to the redwood family, called Taxodiaceae. While closely related and similar in appearance, they are of different species. The Taxodiaceae family of trees also includes the Japanese cedar, the dawn redwoods of central China and the bald cypress (or swamp cypress) common to the Southeastern United states but found all over America’s eastern states. People commonly plant trees in the Taxodiaceae family in ornamental gardens around the world.
Far rarer than the coastal redwood, giant sequoias grow along a 250-mile-long stretch of the often-arid westward facing slopes of California’s Sierra Nevada mountain range, between the elevations of 4,000 and 8,000 feet. The range of the coastal redwood extends from central California 450 miles north into southern Oregon, and, as the name suggests, they usually live within 15 miles of the coast, where the air is normally cool and damp.
The biggest tree on earth by sheer volume, the diameter of a giant sequoia’s trunk can reach 40 feet. The circumference of the General Sherman tree in Sequoia National Park (the largest giant sequoia in the world) is over 102 feet. Giant sequoias can grow as high as 275 feet, with a total volume of wood exceeding 52,000 cubic feet. More slender than their cousins, the coastal redwood nevertheless grows considerably higher. In Humboldt County’s Redwood National and State Park, the tree named Hyperion is the tallest of them all, at over 379 feet in height.
Seeds and Cones
As one might expect, the bulkiest tree on earth has larger cones than does its taller yet less massive relative, though seeds are another matter. The cone of the coastal redwood is about the size of an acorn with seeds no larger than long-grain rice. While the cone of the giant sequoia is roughly three to four times larger than that of the coastal redwood, its miniscule seeds are less than half as big as the redwood’s seeds.
The giant sequoia’s foliage has a scaly appearance similar to that of its fellow conifer, the juniper bush, where the individual needles overlap those riding farther out on the twig and have a tough texture. In contrast, the coastal redwood’s short needles (about ¾ of an inch long) fan out nearly perpendicular to the stem and are often very soft to the touch.
While the wood of both the giant sequoia and the coastal redwood is naturally resistant to decay or invasion by parasitic insects, the giant sequoia’s wood has a rough, coarse texture when compared to the softer coastal redwood. Due to its tendency to resist burning, redwood is a popular if expensive wood for construction. On the other hand, because of their bulk, giant sequoias tend to shatter when logged, which has saved the species from the timber industry.
Both the coastal redwood and the giant sequoia appear reddish from a distance, which is why both are of the redwood (Taxodiaceae) family. However, subtle variations in the coloration of the various barks distinguish the two. The giant sequoia’s bark is reddish-brown in appearance and somewhat brighter than that of the coastal redwood, whose bark is more of a drab chocolate brown color up close. The giant sequoia’s bark has a rough texture, while the coastal redwood’s bark is rather soft.
Like all conifers and indeed all seed-bearing plants on earth, both coastal redwoods and giant sequoias reproduce by dropping their seeds onto fertile ground so they can sprout and grow. The giant sequoia requires intense heat to split the seeds and allow sprouting, however, which is why forest fires are essential to the continuation of the species. Coastal redwoods are one of the few conifers that can propagate by sprouting new trees from stumps, burls, roots or from the branches of blown-over trees.