Coast redwood (Sequoia sempervirens) is a tree species native to the United States. Coast redwood is also called the California redwood. This species is one of the tallest trees on Earth. The coast redwood is one of the oldest living organisms.
I. Appearance and Characteristics
Sequoia sempervirens () is the sole living species of the genus Sequoia in the cypress family Cupressaceae (formerly treated in Taxodiaceae). Common names include coast redwood, coastal redwood and California redwood. It is an evergreen, long-lived, monoecious tree living 1,200–2,200 years or more. This species includes the tallest living trees on Earth, reaching up to 115.9 m (380.1 ft) in height (without the roots) and up to 8.9 m (29 ft) in diameter at breast height. These trees are also among the longest-living organisms on Earth. Before commercial logging and clearing began by the 1850s, this massive tree occurred naturally in an estimated 810,000 ha (2,000,000 acres) along much of coastal California (excluding southern California where rainfall is not sufficient) and the southwestern corner of coastal Oregon within the United States.
The name sequoia sometimes refers to the subfamily Sequoioideae, which includes S. sempervirens along with Sequoiadendron (giant sequoia) and Metasequoia (dawn redwood). Here, the term redwood on its own refers to the species covered in this article but not to the other two species.
The coast redwood normally reaches a height of 60 to 100 m (200 to 330 ft), but will be more than 110 m (360 ft) in extraordinary circumstances, with a trunk diameter of 9 m (30 ft). It has a conical crown, with horizontal to slightly drooping branches. The trunk is remarkably straight. The bark can be very thick, up to 35 cm (1.15 ft), and quite soft and fibrous, with a bright red-brown color when freshly exposed (hence the name redwood), weathering darker. The root system is composed of shallow, wide-spreading lateral roots.
The leaves are variable, being 15–25 mm (5⁄8–1 in) long and flat on young trees and shaded lower branches in older trees. The leaves are scalelike, 5–10 mm (1⁄4–3⁄8 in) long on shoots in full sun in the upper crown of older trees, with a full range of transition between the two extremes. They are dark green above and have two blue-white stomatal bands below. Leaf arrangement is spiral, but the larger shade leaves are twisted at the base to lie in a flat plane for maximum light capture.
The species is monoecious, with pollen and seed cones on the same plant. The seed cones are ovoid, 15–32 mm (9⁄16–1+1⁄4 in) long, with 15–25 spirally arranged scales; pollination is in late winter with maturation about 8–9 months after. Each cone scale bears three to seven seeds, each seed 3–4 mm (1⁄8–3⁄16 in) long and 0.5 mm (1⁄32 in) broad, with two wings 1 mm (1⁄16 in) wide. The seeds are released when the cone scales dry and open at maturity. The pollen cones are ovular and 4–6 mm (3⁄16–1⁄4 in) long.
Its genetic makeup is unusual among conifers, being a hexaploid (6n) and possibly allopolyploid (AAAABB). Both the mitochondrial and chloroplast genomes of the redwood are paternally inherited.
II. How to Grow and Care
Sunlight
Redwood trees require full sun and do not tolerate shade. Make sure the tree is placed in an area where it receives plenty of direct sunlight.
Temperature and humidity
Redwood trees favor climates where the temperatures range between 15 and 100 degrees Fahrenheit with high precipitation levels. The tree’s native range has an average temperature of 40-60 degrees Fahrenheit, with steady dampness provided by the coast and mountain weather systems. If you provide your tree with plenty of moisture and are located in USDA hardiness zones 7-9, it should do just fine.
Watering
Keeping your Redwood tree watered sufficiently is crucial to ensure a healthy tree. While the naturally occurring fog in its native habitat irrigates the tree in the woodlands, residential settings require regular watering until the tree is fully established. Water the tree weekly for the first five years of its life out to its dripline, where the roots absorb the most water.
Soil
Redwood trees prefer well-drained, sandy loam, acidic soil found in their natural habitat. While they can adapt to other soil conditions, they do not tolerate compacted, alkaline, or salty soil. Ensure that the soil is well-draining and acidic.
Fertilizing
Redwood trees typically do not require supplemental fertilisers and can thrive without any added nutrients. However, watch out for yellowing needles during the summer, which may be caused by alkaline or neutral soil. The redwood prefers acidic soil with an ideal pH of 6.5. Test the soil pH level if you notice yellowing.
Planting Instructions
Redwood trees can be grown in various regions. Here are the steps to grow.
Firstly, you need to collect redwood seeds. Usually, the tree flowers from December to February. The flower creates cones that start to fall at the beginning of the rainy season. This cone consists of a seed that is an inch long.
When you can get the cone, you have to place the cone in a ziplock bag. Use some perlite inside the bag and keep it in a shady area.
When you find a small sprout, you have to transfer the seed to a huge pot. Make sure to add some coconut coir, acid fertiliser, macronutrients, micronutrients, and perlite. Also, keep the soil a bit moist so that the seed and the sprout will not dry.
After good germination, place the sapling in a very sunny area where you want to grow the tree.
Water the sapling daily, but do not overwater it.
Pruning
Redwood trees require minimal pruning. Remove dead and broken branches and lower branches to expose the attractive bark. The needles and broken branches around the bottom of the tree will create its own naturally occurring mulch called duff.
Propagation
Weed Control
Pests and Diseases
Redwood trees are highly resistant to pests and diseases once mature. Even a tree that is temporarily plagued by pests will not suffer any ill effects.
III. Uses and Benefits
- Ornamental uses
Coast redwood is a popular tree prized for its red trunk and green needles. It is used as a decorative plant in yards and is an essential tree in evergreen forest gardens. Plant it with hostas and ferns for texture and color at the base.
- Other uses
Redwood trees are known for durable timber, which is fire-resistant, fungus-resistant, and insect resistant. The timber is known for resistance against decay. As timber has so many good properties, it is used in carpentry. Also, in some construction works, timber is used. Furniture, fence, panels, etc., are some major uses of the redwood tree.
In the past, timber was also used for producing water tanks and pots.
As the redwood tree is fire resistant, it is used in various outdoor projects too.
