Being the tallest tree species, with a small range and an extremely long lifespan, many redwoods are preserved in various state and national parks; many of the largest specimens have their own official names.

[9] Historically, the American naturalist, physician and founder member of the California Academy of Sciences, William P. Gibbons (1812–1897) described in 1893 the hollow shell of a coast redwood in the Oakland Hills of Alameda County with diameter of 9.9 metres (32 ft) at breast height.

The bark can be very thick, up to 35 cm (1.15 ft), and quite soft and fibrous,[9] with a bright red-brown color when freshly exposed (hence the name redwood), weathering darker.

Leaf arrangement is spiral, but the larger shade leaves are twisted at the base to lie in a flat plane for maximum light capture.

Thus, Yang and colleagues hypothesize that the inconsistent relationships among Metasequoia, Sequoia, and Sequoiadendron could be a sign of reticulate evolution (in which two species hybridize and give rise to a third) among the three genera.

[16] The species name "sempervirens" means "evergreen", thought to be because of its previous placement in the same genus as Taxodium distichum (baldcypress) of the southeastern USA.

The southernmost grove is in the Southern Redwood Botanical Area, just north of the national forest's Salmon Creek trailhead and near the San Luis Obispo County line.

The ancient range of the genus is considerably greater, with relatives of the coast redwood living in Europe and Asia prior to the Quaternary geologic period.

[28][29] The authors of a 2022 paper suggest, "Were it not for the remarkable ability to sprout after fire, many southern forests may have lost their Sequoia component long ago.

[31] The ability of Coast Redwood to live for more than a thousand years, along with its unusual capacity to resprout from its root crown when felled by natural or human causes, have earned this species the label of "carbon-sequestration champion.

"[32] Its potential to contribute toward climate change mitigation, as well as its demonstrated ability to thrive in coastal regions of the Pacific Northwest,[33][34] led to the formation of a citizen group in Seattle, Washington undertaking assisted migration of this species hundreds of miles north of its native range.

In contrast to cautionary statements made by forestry professionals assessing other tree species for assisted migration,[37] the citizens involved with the group known as PropagationNation had met with little controversy until in 2023 a national news outlet published a lengthy article that cast a favorable light on their efforts.

The New York Times Magazine wrote: Not wanting to cause ecological problems by planting the trees across the Pacific Northwest, [Philip] Stielstra would eventually contact one of the foremost experts on the coast redwood, a botanist and forest ecologist named Stephen Sillett, at Cal Poly Humboldt, and ask if moving redwoods north was safe.

[39] Even before the controversy developed in Washington state, professionals in Canada were documenting horticultural plantings of the California species already in place in southwestern British Columbia.

The bottleneck entails a lack of lowland passages through the Oregon Coast Range north of the Chetco River, coupled with the absence of coastal landscapes beyond storm salt-spray and tsunami inundation — for which this conifer species is highly intolerant.

This forest community includes coast Douglas-fir, Pacific madrone, tanoak, western hemlock, and other trees, along with a wide variety of ferns, mosses, mushrooms, and redwood sorrel.

[58] Self-pruning of its lower limbs as height is gained is a crucial adaptation to prevent ground fires from rising into the canopy, where branch bark is thin and leaves are vulnerable.

[57] When the first humans arrived in North America, redwoods thrived in regions where ground fires were intentionally set by indigenous populations on a seasonal basis.

Governmental policies aimed at suppressing all natural and human-caused fires, even in parks and wilderness areas, amplified the accumulation of dense undergrowth and woody debris.

P. H. Shaughnessy, Chief Engineer of the San Francisco Fire Department wrote: In the recent great fire of San Francisco, that began April 18th, 1906, we succeeded in finally stopping it in nearly all directions where the unburned buildings were almost entirely of frame construction, and if the exterior finish of these buildings had not been of redwood lumber, I am satisfied that the area of the burned district would have been greatly extended.Because of its impressive resistance to decay, redwood was extensively used for railroad ties and trestles throughout California.

[54][66] The introduction of steam engines let crews drag logs through long skid trails to nearby railroads,[54] furthering the reach of loggers beyond the land near rivers previously used to transport trees.

[66] This method of harvesting, however, disturbed large amounts of soil, producing secondary-growth forests of species other than redwood such as Douglas-fir, grand fir, and western hemlock.

[68] Other areas of successful cultivation outside of the native range include Great Britain, Italy, France,[69] Haida Gwaii, middle elevations of Hawaii, Hogsback in South Africa, the Knysna Afromontane forests in the Western Cape, Grootvadersbosch Forest Reserve near Swellendam, South Africa and the Tokai Arboretum on the slopes of Table Mountain above Cape Town, a small area in central Mexico (Jilotepec), and the southeastern United States from eastern Texas to Maryland.

Coast redwood trees were used in a display at Rockefeller Center and then given to Longhouse Reserve in East Hampton, Long Island, New York, and these have now been living there for over twenty years and have survived at 2 °F (−17 °C).

[71][72] Fairly solid evidence indicates that coast redwoods were the world's largest trees before logging, with numerous historical specimens reportedly over 122 m (400 ft).

[73]: 16, 42  The theoretical maximum potential height of coast redwoods is thought to be limited to between 122 and 130 m (400 and 427 ft), as evapotranspiration is insufficient to transport water to leaves beyond this range.

A tree reportedly 129.2 m (424 ft) tall was felled in November 1886 by the Elk River Mill and Lumber Company in Humboldt County, yielding 79,736 marketable board feet from 21 cuts.

[8] The tree was discovered in Redwood National Park during mid-2006 by Chris Atkins and Michael Taylor, and is thought to be the world's tallest living organism.

[citation needed] Recent research news reports that albino redwoods can store higher concentrations of toxic metals, going so far as comparing them to organs or "waste dumps".

Redwood canopy soil forms from leaf and organic material litter shedding from upper portions of the tree, accumulating and decomposing on larger branches.