Details of trees plants and summary on their care and cultivation

Actinidia Chinensis Actinidia chinensis Scientific classification Kingdom: Plantae Clade : Angiosperms Clade : Eudicots Clade : Asterids Ord...

Actinidia Chinensis

Actinidia Chinensis

Actinidia chinensis
Actinidia chinensis1.jpg
Scientific classificationedit
Kingdom:Plantae
Clade:Angiosperms
Clade:Eudicots
Clade:Asterids
Order:Ericales
Family:Actinidiaceae
Genus:Actinidia
Species:
A. chinensis
Binomial name
Actinidia chinensis

Actinidia chinensis is a fruit tree and medicinal plant native to China. It is closely related to Actinidia deliciosa, the source of the common kiwifruit. It is pollinated by bees.

Habitat

Fruit of Actinidia chinensis

In its native habitat Actinidia chinensis grows in thickets, thick (oak) forests (e.g. Quercus aquifolioidesQuercus oxyodonQuercus lamellosa), and light secondary forests and bushland. A. chinensis prefers slopes and likes also to grow in ravines, top heights of 200-230m, relative to the local microclimate. In Western gardens it may range 30 feet in all directions, making it unsuitable for all but the largest spaces unless pruned back hard at the end of every growing season.

Origin

The origin of Actinidia chinensis is supposed to be the northern Yangtze river valley. In China, Actinidia chinensis is nowadays dispersed in the entire southeast of the country.

Herbarium specimens, but not plants, were forwarded to the Royal Horticultural Society by the British plant hunter Robert Fortune, from which Jules Émile Planchon named the new genus in the London Journal of Botany, 1847. Charles Maries, collecting for Messrs Veitch noted it in Japan, but the introduction to Western horticulture was from E.H. Wilson, who sent seeds collected in Hupeh to Veitch in 1900.

Uses

Inner pulp of the fruit, edible

The fruits, the size of a walnut, are edible. It was first grown commercially in New Zealand, where it has been superseded by Actinidia deliciosa, or Kiwifruit.

It is used in traditional Chinese medicine.

Smilax aspera Smilax aspera Scientific classification Kingdom: Plantae Clade : Angiosperms Clade : Monocots Order: Liliales Family: Smilacac...

Smilax aspera

Smilax aspera

Smilax aspera
Smilax aspera.jpg
Scientific classificationedit
Kingdom:Plantae
Clade:Angiosperms
Clade:Monocots
Order:Liliales
Family:Smilacaceae
Genus:Smilax
Species:
S. aspera
Binomial name
Smilax aspera
Synonyms

Smilax aspera, with common names common smilaxrough bindweedsarsaparille, and Mediterranean smilax, is a species of flowering vine in the greenbriar family.

Description

Smilax aspera is a perennial, evergreen climber with a flexible and delicate stem, with sharp thorns. The climbing stem is 1–4 metres (3 ft 3 in–13 ft 1 in) long. The leaves are 8–10 centimetres (3.1–3.9 in) long, petiolated, alternate, tough and leathery, heart-shaped, with toothed and spiny margins. It is the monocot with reticulate type of venation. Also the midrib of the underside of the leaves are provided with spines. The flowers, very fragrant, are small, yellowish or greenish, gathered in axillary racemes. The flowering period in Mediterranean regions extends from September to November. The fruits are globose berries, gathered in clusters, which ripen in Autumn. They are initially red, later turn black. They have a diameter of 8–10 millimetres (0.31–0.39 in) and contain one to three tiny and round seeds. They're insipid are unpalatable to humans, and are a source of nourishment for many species of birds.

Distribution

It is widespread in Central Africa (Democratic Republic of CongoKenyaEthiopia), Mediterranean Europe (AlbaniaCroatiaGreeceItalyMaltaFrancePortugalSpain), temperate Asia (CyprusIsraelJordanLebanonSyriaTurkey) and tropical Asia (IndiaBhutanNepal). It is also naturalized in other regions.

Habitat

It grows in the woods and scrubs, at an altitude of 0–1,200 metres (0–3,937 ft) above sea level.

Gallery

Chamaecyparis Thyoides Chamaecyparis thyoides Chamaecyparis thyoides  near the edge of a bog in  New Jersey Conservation status Least Concer...

Chamaecyparis Thyoides

Chamaecyparis Thyoides

Chamaecyparis thyoides
2013-05-10 13 29 55 Atlantic White Cedar near the edge of a bog along the Mount Misery Trail in Brendan T. Byrne State Forest, New Jersey.jpg
Chamaecyparis thyoides near the edge of a bog in New Jersey
Conservation status

Least Concern (IUCN 2.3)
Scientific classificationedit
Kingdom:Plantae
Division:Pinophyta
Class:Pinopsida
Order:Pinales
Family:Cupressaceae
Genus:Chamaecyparis
Species:
C. thyoides
Binomial name
Chamaecyparis thyoides
(L.) Britton, Sterns & Poggenb.
Chamaecyparis thyoides range map 2.png
Natural range of Chamaecyparis thyoides

Chamaecyparis thyoides (Atlantic white cedarAtlantic white cypresssouthern white cedarwhitecedar, or false-cypress), a species of Cupressaceae, is native to the Atlantic coast of North America and is found from southern Maine to Georgia and along the Gulf of Mexico coast from Florida to Mississippi. It is one of two species of Chamaecyparis found in North America. C. thyoides resides on the East Coast and C. lawsoniana can be found on the West Coast. There are two geographically isolated subspecies, treated by some botanists as distinct species, by others at just varietal rank: Chamaecyparis thyoides thyoides and Chamaecyparis thyoides henryae (H.L.Li) E.Murray (syn. Chamaecyparis thyoides subsp. henryae (H.L.Li) Little; Chamaecyparis henryae H.L.Li) The species grows in forested wetlands where they tend to dominate the canopy. The trees are associated with a wide variety of other wetland species because of their wide north-south range. The remaining populations are now found mostly in remote locations that would be difficult to harvest, so its popularity as a source of lumber has decreased.

Distribution and habitat

Chamaecyparis thyoides grows within 20 and 100 m of the coastline and less than 50 m above sea level along much of the East Coast and Gulf Coast. Rare populations grow in the foothills of the Appalachian Mountains, where the tree may be found up to 460 m above sea level. Nationally, Atlantic white cedar are protected in the Great Dismal Swamp National Wildlife RefugeAlligator River National Wildlife RefugeCape Cod National SeashoreCroatan National ForestFrancis Marion National ForestOcala National Forest, and Apalachicola National Forest. Altered fire regimes, logging, and draining of wetlands outside of the few protected areas have all contributed to the general decrease in the size and occurrences of Atlantic white cedar strands. The tree is listed as Rare in Georgia and New York, of Special Concern in Maine, and Extirpated in Pennsylvania.

Chamaecyparis thyoides lives almost exclusively in freshwater wetlands and are considered an obligate wetland species. It prefers habitats where the soil is saturated with water at least during the majority of the growing season. The soils in these regions have a thick organic layer, often classified as a histic surface horizon, with sandy material at greater depths and poor drainage. Atlantic white cedar wetlands are acidic and there is little oxygen stored in the soil because water has displaced the air. Plants that live in these environments must be specially adapted to such conditions.

Though the tree is not listed as threatened, Atlantic white cedar wetlands are considered a globally threatened ecosystem, and often serve as carbon sinks because of their peat-building abilities.

Ecology

Red maple and black gum trees are often found in the canopy along with Atlantic white cedar throughout its range. Sphagnum mosses also often grow in these wetlands. The caterpillar of the Hessel's Hairstreak butterfly feed exclusively on C. thyoides, where its green color helps it to be camouflaged.

The trees themselves grow on hummocks, small mounds, with water pooling in the depressions surrounding them. This keeps the tree from being underwater year-round and helps to protect from floods. The tree benefits from periodic low-intensity fires which expose seedlings to sunlight and limit competition with other canopy flora, particularly Red Maple. Too frequent or intense fires or flooding are damaging to seedlings stored in the top layer of soil and full-grown trees.

Description

Chamaecyparis thyoides is an evergreen coniferous tree usually growing to 20–28 m (66–92 ft) (but may grow up to 35 m (115 ft)) tall with an average diameter of 0.8 m (2 ft 7 in), up to 2 m (6 ft 7 in), and feathery foliage in moderately flattened sprays, green to glaucous blue-green in color. The leaves are scale-like, 2–4 mm (332532 in) long, and produced in opposite decussate pairs on somewhat flattened shoots; seedlings up to a year old have needle-like leaves. The tree is bare of branches for three-fourths of the trunk height and the bark can be ash-gray to reddish brown. Bark is smooth on juveniles, but mature trees have deep ridges and bark as thick as 5 cm (2 in). C. thyoides is monoecious, so a single tree will carry both the pollen and seeds needed for reproduction in cones. The seed cones are globose, 4–9 mm (5321132 in) diameter, with 6-10 scales (1-2 seeds per scale), green or purple, maturing to brown in 5–7 months after pollination. The pollen cones are yellow but turn brown as the tree matures, 1.5–3 mm (11618 in) long and 1–2 mm (132332 in) broad, releasing their yellow pollen once a year in spring. The tree begins bearing seeds at 4–5 years, but does not reach full maturity and start producing cones until it is 10-20 year olds. Seeds are dispersed nearly every year and travel by wind. Height and diameter of the tree increase steadily until the tree is 50 years old, at which point height growth slows. Both height and diameter no longer increase once the tree is 100 years old. Stands are generally all younger than 200 years, though some trees as old as a 1000 years have been reported. Because they have relatively shallow roots, C. thyoides are vulnerable to being blown over by wind.

Subspecies variation

  • Chamaecyparis thyoides thyoides: Leaves and immature cones usually glaucous blue-green; cones mature to dark brown-black; facial leaves flat, not ridged, but with visible glands.
  • Chamaecyparis thyoides henryae: Leaves and immature cones green, not glaucous; cones mature to light brown; facial leaves with a longitudinal ridge with glands less obvious or absent.

Cultivation and uses

Foliage and seed cones

Chamaecyparis thyoides is of some importance in horticulture, with several cultivars of varying crown shape, growth rates and foliage color having been selected for garden planting. Named cultivars include 'Aurea' (yellow foliage), 'Heatherbun' (dwarf, purple in winter), 'Andelyensis' (dwarf, dense foliage), 'Ericoides' (juvenile foliage), and 'Glauca' (strongly glaucous foliage). In some locations, particularly Mobile County, Alabama, the tree is cultivated as a Christmas tree.

Wood

Its wood is considered hardy, as it is resistant to decay and warping in a variety of temperatures and moisture levels. The most common use of white cedar wood is lumber, for which stands usually require 70 years of growth from germination to harvest. The lumber may be used in house construction, though scarcity of Atlantic white cedar makes it difficult to be used as the primary material. The wood was favored for use as roof shingles because it is lightweight, but has since been replaced by cheaper and more fire-resistant materials such as asphalt. The durability of the heartwood makes it popular for use as siding and paneling, and the less resistant sapwood has been used for interior finishes. White cedar lumber has also been used in boat construction, but this requires much older, larger trees. North Carolina is the greatest producer of lumber for boat construction because it has the greatest number of old-growth C. thyoides forests. Other uses include fencing, telephone and electric poles, woodenware, duck decoys, lawn furniture, and as Christmas trees.

Gallery

Chamaecyparis Lawsoniana Chamaecyparis lawsoniana Old-growth stand of  C. lawsoniana  in California Conservation status Near Threatened  ( I...

Chamaecyparis Lawsoniana

Chamaecyparis Lawsoniana

Chamaecyparis lawsoniana
Chamaecyparis lawsoniana Dorena1.jpg
Old-growth stand of C. lawsoniana in California
Conservation status

Near Threatened (IUCN 3.1)
Scientific classificationedit
Kingdom:Plantae
Division:Pinophyta
Class:Pinopsida
Order:Pinales
Family:Cupressaceae
Genus:Chamaecyparis
Species:
C. lawsoniana
Binomial name
Chamaecyparis lawsoniana
Chamaecyparis lawsoniana range map 2.png
Natural range of Port Orford cedar

Chamaecyparis lawsoniana, known as Port Orford cedar or Lawson cypress, is a species of conifer in the genus Chamaecyparis, family Cupressaceae. It is native to Oregon and northwestern California, and grows from sea level up to 1,500 m (4,900 ft) in the valleys of the Klamath Mountains, often along streams.

Description

It is a large evergreen tree, maturing up to 197 ft (60 m) tall or more, with trunks 4–7 ft (1.2–2 m) in diameter, with feathery foliage in flat sprays, usually somewhat glaucous (i.e. blue-green) in color. The leaves are scale-like, 18316 inch (3–5 mm) long, with narrow white markings on the underside, and produced on somewhat flattened shoots. The foliage gives off a rather pungent scent, not unlike parsley. The seed cones are globose, 932916 inch (7–14 mm) diameter, with 6-10 scales, green at first, maturing brown in early fall, 6–8 months after pollination. The male cones are 18532 inch (3–4 mm) long, dark red, turning brown after pollen release in early spring. The bark is reddish-brown, and fibrous to scaly in vertical strips.

History and names

It was first discovered (by Euro-Americans) near Port Orford in Oregon and introduced into cultivation in 1854, by collectors working for Charles Lawson FRSE of the Lawson & Son nursery in Edinburgh, Scotland, after whom it was named as Lawson Cypress by the describing botanist Andrew Murray. The USDA officially calls it by the name Port Orford cedar, as do most people in its native area, but some botanists prefer to use the name Lawson cypress (or in very rare instances Port Orford cypress) instead. The name "Lawson's cypress" is widely used in horticulture.

Prehistory

The extinct Eocene species Chamaecyparis eureka, known from fossils found on Axel Heiberg Island in Canada, is noted to be very similar to Chamaecyparis pisifera and C. lawsoniana.

Wood

The wood is light yet has great strength and rot resistance, and is particularly highly valued in east Asia, with large amounts being exported to Japan where it is in high demand for making coffins, and for shrines and temples. Its lumber is also known for its highly fragrant ginger aroma. Due to the straightness of its grain, it is also one of the preferred woods for the manufacture of arrow shafts. It is also considered an acceptable, though not ideal, wood for construction of aircraft.

However, it is considered more than acceptable for use in stringed instruments. Its fine grain, good strength and tonal quality are highly regarded for soundboards in guitar making.

Cultivation

Chamaecyparis lawsoniana thrives best in well-drained but moist soils, in a fairly sheltered position in full sun.Several hundred named cultivars of varying crown shape, growth rates and foliage colour have been selected for planting in parks and gardens. In the UK the following have gained the Royal Horticultural Society's Award of Garden Merit (confirmed 2017):-

NameHeight (m)Spread (m)ShapeFoliage ColourRef.
'Aurea Densa'1.51.0broadly conicalyellow-green
'Chilworth Silver'2.51.0broadly columnarsilver-blue
'Dik's Weeping'12.04.0columnar, weepingblue-green
'Ellwoodii'8.04.0columnargrey-green
'Ellwood's Gold'4.01.0columnaryellow/grey-green
'Ellwood's Pillar'2.51.5narrowly columnargrey-green
'Fletcheri'12.04.0columnargrey-green
'Gimbornii'2.52.5roundedgrey-green
'Golden Wonder'20.04.0columnaryellow-green
'Grayswood Feather'4.01.5narrowly columnargreen
'Green Globe'0.30.3roundeddark green
'Imbricata Pendula'8.04.0conical, weeping, pendulousgreen
'Kilmacurragh'12.04.0columnardark green
'Lanei Aurea'8.02.5columnaryellow-green
'Little Spire'2.51.5conicaldark green
'Minima Aurea'1.01.0conicalyellow-green
'Minima Glauca'2.52.5roundedblue-green
'Pembury Blue'12.00+8.00conicalblue-green
'Pygmaea Argentea'2.51.0roundedcream/blue-green
'Stardust'4.01.5columnaryellow-green
'Summer Snow'2.51.5conicalcream/green
'Triomf van Boskoop'25.08.0broadly columnargrey-green
'Wisselii'12.0+4.0narrowly conicalblue-green
'Wissel's Saguaro'6.01.0narrow, uprightblue-green

Disease

In the wild, the species is seriously threatened by a root disease caused by the introduced oomycete pathogen, Phytophthora lateralis. This disease is also a problem for horticultural plantings in some parts of North America. The tree is sometimes killed, though less often, by other species of Phytophthora.

Phytophthora lateralis infection begins when mycelium, from a germinated spore, invade the roots. The infection then spreads through the inner bark and cambium around the base of the tree. Spread up the trunk is generally limited. Infected tissue dies and effectively girdles the tree. Large trees are more likely to be infected than small trees due to larger root areas (although all trees at the edges of infected streams will eventually succumb). However, large trees can often live with the infections for a longer duration (up to several years).

C. lawsoniana in streamside populations are highly susceptible to Phytophthora lateralis infection. However, the rate of Phytophthora spread through populations in dry upland areas appears to be slow. Phytophthora lateralis spreads through water via mobile spores (zoospores). The fungus also produces resting spores (chlamydospores) that can persist in soil for a long period of time. New infections generally begin when soil is transferred from an infected population to a non-infected population via human or animal movement. After initial infection in streamside populations, secondary spread via zoospores quickly infects all downstream individuals.

Human facilitated spread is thought to be responsible for most new, and all long-distance, infections. Soil on vehicle tires, especially logging trucks and other off road vehicles, is considered the most pressing problem due to the volume of soil that can be carried and the traffic rate in and between susceptible areas. Spread on boots and mountain bike tires has also been suggested and probably contributes to new infections locally. Animal facilitated spread is thought to occur, but is localized.

The Bureau of Land Management (BLM) and United States Forest Service (USFS) attempt to prevent Phytophthora spread through road closures, monitoring, research and education. Research has focused on determining the dynamics and mechanisms of spread, as well as attempts to breed resistant trees. One solution against Phytophtera is known generically as Mancozeb and also commercially known as Dithane (C). Commercial preparations of the parasitic fungus Pythium oligandrum are licensed for pest control, and documented to predate many species of Phytophthora.

Calocedrus Decurrens Calocedrus decurrens Tree in  Yosemite National Park , California Conservation status Least Concern  ( IUCN 3.1 ) Scien...

Calocedrus Decurrens

Calocedrus Decurrens

Calocedrus decurrens
A two-trunked tree in a grassy meadow, with steep terrain, including a granite cliff, in the background
Tree in Yosemite National Park, California
Conservation status

Least Concern (IUCN 3.1)
Scientific classificationedit
Kingdom:Plantae
Division:Pinophyta
Class:Pinopsida
Order:Pinales
Family:Cupressaceae
Genus:Calocedrus
Species:
C. decurrens
Binomial name
Calocedrus decurrens
Distribution of Calocedrus decurrens in the Western United States
Distribution of Calocedrus decurrens in the Western United States
Synonyms
  • Abies cupressoides Poir.
  • Heyderia decurrens (Torr.) K.Koch
  • Libocedrus decurrens Torr.
  • Thuja craigana A.Murray bis
  • Thuja decurrens (Torr.) Voss

Calocedrus decurrens, with the common names incense cedar and California incense-cedar (syn. Libocedrus decurrens Torr.), is a species of conifer native to western North America, with the bulk of the range in the United States, from central western Oregon through most of California and the extreme west of Nevada, and also a short distance into northwest Mexico in northern Baja California. It grows at altitudes of 50–2,900 metres (160–9,510 ft). It is the most widely known species in the genus, and is often simply called 'incense cedar' without the regional qualifier.

Description

Calocedrus decurrens is a large tree, typically reaching heights of 40–60 m (130–195 ft) and a trunk diameter of up to 3 m (9.8 ft). The largest known tree, located in Umpqua National ForestOregon, is 69.8 m (229 ft 0 in) tall with a 175-centimeter (69-inch) diameter trunk. It has a broad conic crown of spreading branches. The bark is orange-brown weathering grayish, smooth at first, becoming fissured and exfoliating in long strips on the lower trunk on old trees.

The foliage is produced in flattened sprays with scale-like leaves 2–15 mm (3321932 in) long; they are arranged in opposite decussate pairs, with the successive pairs closely then distantly spaced, so forming apparent whorls of four; the facial pairs are flat, with the lateral pairs folded over their bases. The leaves are bright green on both sides of the shoots with only inconspicuous stomata. The foliage, when crushed, gives off an aroma somewhat akin to shoe-polish.

The seed cones are 20–35 mm (341 38 in) long, pale green to yellow, with four (rarely six) scales arranged in opposite decussate pairs; the outer pair of scales each bears two winged seeds, the inner pair(s) usually being sterile and fused together in a flat plate. The cones turn orange to yellow-brown when mature about 8 months after pollination. The pollen cones are 6–8 mm (14516 in) long.

Ecology

This tree is the preferred host of a wood waspSyntexis libocedrii a living fossil species which lays its eggs in the smoldering wood immediately after a forest fire. The tree is also host to incense-cedar mistletoe (Phoradendron libocedri), a parasitic plant which can often be found hanging from its branches.

The incense cedar is one of the most fire and drought tolerant plants in California. Although the tree is killed by hot, stand-replacing crown fire, it spreads rapidly after lower intensity burns. This has given the incense cedar a competitive advantage over other species such as the bigcone Douglas-fir in recent years.

Uses

The wood is the primary material for wooden pencils, because it is soft and tends to sharpen easily without forming splinters.

Native Americans

The Native Americans of California used the plant in traditional medicine, basket makinghunting bows, building materials, and to produce fire by friction.

The Maidu Concow tribe name for the plant is hö'-tä (Konkow language).

Cultivation

Calocedrus decurrens is cultivated by plant nurseries as an ornamental tree, for planting in gardens and parks. It is used in traditional, xeriscapicnative plant, and wildlife gardens; and used in designed natural landscaping and habitat restoration projects in California. It is valued for its columnar form and evergreen foliage textures.

The tree is also grown in gardens and parks in cool summer climates, including the Pacific Northwest in the Northwestern United States and British Columbia, eastern Great Britain and continental Northern Europe. In these areas it can develop an especially narrow columnar crown, an unexplained consequence of the cooler climatic conditions that is rare in trees within its warm summer natural range in the California Floristic Province. Other cultivated species from the family Cupressaceae can have similar crown forms. This plant has gained the Royal Horticultural Society's Award of Garden Merit.

Platycladus Chinese arborvitae Platycladus orientalis  in its natural habitat in  Simatai ,  Great Wall of China Conservation status Near Th...

Platycladus

Platycladus

Chinese arborvitae
Platycladus orientalis Simatai.jpg
Platycladus orientalis in its natural habitat in SimataiGreat Wall of China
Conservation status

Near Threatened (IUCN 3.1)
Scientific classificationedit
Kingdom:Plantae
Division:Pinophyta
Class:Pinopsida
Order:Pinales
Family:Cupressaceae
Subfamily:Cupressoideae
Genus:Platycladus
Spach
Species:
P. orientalis
Binomial name
Platycladus orientalis
Synonyms

Platycladus is a distinct genus of evergreen coniferous tree in the cypress family Cupressaceae, containing only one species, Platycladus orientalis, also known as Chinese thujaOriental arborvitaeChinese arborvitaebiota or oriental thuja. It is native to northeastern parts of eastern Asia and north Asia, but is also now naturalised as an introduced species elsewhere in Asia.

Taxonomy

Although generally accepted as the only member of its genus, it has been suggested that the closely related species Microbiota decussata could be included in Platycladus, but this is not widely followed. Other fairly close relatives are Juniperus and Cupressus, both of these genera being graft-compatible with Platycladus. In older texts, Platycladus was often included in Thuja, which is reflected in one of its common names, "oriental thuja". But it is only distantly related to the genus Thuja. Differences include its distinct cones, wingless seeds, and its almost scentless foliage.

Etymology

The binomial Platycladus means "with broad or flattened shoots". The qualifier orientalis refers to its native habitat in China.

The common name 'arborvitae' is from Latin, 'tree of life', and is based on its association with long life and vitality in Buddhist thought in China. This is probably based on the tree's unchanging evergreen nature in the cold dry climate of northwest China, and its longevity; some of the larger specimens planted around Buddhist temples in China are said to be in excess of 1,000 years old. It is called cèbǎi (側柏) in Chinese.

Description

monoecious tree, it is small, slow-growing, reaching 15–20 m (49–66 ft) and 0.5 m (1 ft 8 in) trunk diameter (exceptionally to 30 m or 98 ft tall and 2 m or 6 ft 7 in diameter in very old trees). The foliage forms in flat sprays with scale-like leaves 2–4 mm (0.08–0.16 in) long, which are bright green in colour but may turn brownish or coppery orange in winter. The cones are 1.5–2.5 cm (58–1 in) long, green ripening brown in about eight months from pollination, and have 6–12 thick scales arranged in opposite pairs. The seeds are 4–6 mm (0.16–0.24 in) long, with no wing.

The branches are relatively short, loosely arranged and, usually, sharply directed upwards, and the bark, brownish, is detached in narrow vertical strips. The twigs are compressed and are arranged in vertical planes. The leaves, arranged in four rows, fleshy, opposite, decussate, truncated, imbricated as adults, somewhat curved inwards, of uniform green color and with a resiniferous gland on the underside. The female cones, of pink-salmon color and later bluish-greenish when immature, centimetric and of annual maturation, are oval with 6-8 flattened, thick scales, coriaceous and provided with an apical hook.

Distribution

It is native to northwestern China, but it is delicate to distinguish the areas where they are native safely from those where they have been introduced. It is distributed in ManchuriaRussian Far East (Amur and Khabarovsk), and now it is naturalised in KoreaJapanIndia and Iran as well. It is also cultivated in many parts of the world in parks, gardens, home yards, cemeteries and for hedges.

Uses

Resistant to drought, it is very often used as an ornamental tree, both in its homeland, where it is associated with long life and vitality, and very widely elsewhere in temperate climates. It is suitable for form cuts and year-round opaque hedges, but also forms impressive slender solitary trees. Several cultivars have been selected, of which 'Aurea Nana' has gained the Royal Horticultural Society's Award of Garden Merit.

The wood is used in Buddhist temples both for (lavairos) construction work, and chipped, for incense burning. Its twigs and leaves contain 0.12% essential oil containing pinene and probably caryophyllene. The roots contain up to 2.75% of gasoline.

Gallery

Thuja Plicata Thuja plicata An old tree in  Vancouver Conservation status Least Concern  ( IUCN 3.1 ) Scientific classification Kingdom: Pla...

Thuja Plicata

Thuja Plicata

Thuja plicata
Thuja plicata Vancouver.jpg
An old tree in Vancouver
Conservation status

Least Concern (IUCN 3.1)
Scientific classificationedit
Kingdom:Plantae
Division:Pinophyta
Class:Pinopsida
Order:Pinales
Family:Cupressaceae
Genus:Thuja
Species:
T. plicata
Binomial name
Thuja plicata
Donn ex D.Don
Thuja plicata range.png
Range of T. plicata in the Pacific Northwest

Thuja plicata, commonly called western redcedar or Pacific redcedargiant arborvitae or western arborvitaegiant cedar, or shinglewood, is a species of Thuja, an evergreen coniferous tree in the cypress family Cupressaceae native to western North America. It is not a true cedar of the genus Cedrus.

Distribution

Thuja plicata is among the most widespread trees in the Pacific Northwest. It is associated with Douglas-fir and western hemlock in most places where it grows. It is found at the elevation range of sea level to a maximum of 2,290 m (7,510 ft) above sea level at Crater Lake in Oregon. In addition to growing in lush forests and mountainsides, western redcedar is also a riparian tree, growing in many forested swamps and streambanks in its range. The tree is shade-tolerant and able to reproduce under dense shade.

It has been introduced to other temperate zones, including western EuropeAustralia (at least as far north as Sydney), New Zealand, the eastern United States (at least as far north as Central New York), and higher elevations of Hawaii.

The species is naturalized in Britain.

Description

Thuja plicata is a large to very large tree, ranging up to 65 to 70 m (213 to 230 ft) tall and 3 to 4 m (9.8 to 13.1 ft) in trunk diameter, exceptionally even larger. Trees growing in the open may have a crown that reaches the ground, whereas trees densely spaced together will exhibit a crown only at the top, where light can reach the leaves. It is long-lived; some individuals can live well over a thousand years, with the oldest verified being 1460 years.

The foliage forms flat sprays with scale-like leaves in opposite pairs, with successive pairs at 90 degrees to each other. The foliage sprays are green above and green marked with whitish stomatal bands below; they are strongly aromatic, with a scent reminiscent of pineapple when crushed. The individual leaves are 1 to 4 mm (0.039 to 0.157 in) long and 1 to 2 mm (0.039 to 0.079 in) broad on most foliage sprays, but up to 12 mm (0.47 in) long on strong-growing lead shoots.

The cones are slender, 10 to 18 mm (0.39 to 0.71 in) long, and 4 to 5 mm (0.16 to 0.20 in) broad, with 8 to 12 (rarely 14) thin, overlapping scales. They are green to yellow-green, ripening brown in fall about six months after pollination, and open at maturity to shed the seeds. The seeds are 4 to 5 mm long and 1 mm (0.039 in) broad, with a narrow papery wing down each side. The pollen cones are 3 to 4 mm (0.12 to 0.16 in) long, red or purple at first, and shed yellow pollen in spring.

Taxonomy and name

Western red-cedars on Keats Island, British Columbia, in May 2017

Thuja plicata is one of two Thuja species native to North America, the other being Thuja occidentalis. The species name plicata derives from the Latin word plicāre and means "folded in plaits" or "braided," a reference to the pattern of its small leaves.

Most authorities, both in Canada and the United States cite the English name in two words as western redcedar, or occasionally hyphenated as western red-cedar, to indicate it is not a true cedar (Cedrus), but it is also cited as western red cedar in some popular works. In the American horticultural trade, it is also known as the giant arborvitae, by comparison with arborvitae for its close relative Thuja occidentalis. Other names include giant redcedar, Pacific redcedar, shinglewood, British Columbia cedar, canoe cedar, and red cedar. Arborvitae comes from the Latin for "tree of life"; coincidentally, Native Americans of the West coast also address the species as "long life maker".

One endonymous name for the tree is the Halkomelem word xepá:y, from the roots xíp, meaning "scratch" or "line", and á:y, "bark"; the former root may be in reference to both the lined or "folded/braided" appearance of the bark and the tree's ubiquity in carving and other forms of woodwork.

Notable specimens

The largest living specimen is the Cheewhat Giant, in Pacific Rim National Park Reserve on Vancouver Island, at 15,870 cubic feet (449 m3). The tallest known individual is the Willaby Creek Tree south of Lake Quinault, 195 feet (59 m) in height.

The "Quinault Lake Redcedar" was the largest western redcedar in the world.

The "Quinault Lake Redcedar" was the largest known western redcedar in the world, with a wood volume of 17,650 cubic feet (500 m3). Located near the northwest shore of Lake Quinault north of Aberdeen, Washington, about 34 km (21 mi) from the Pacific Ocean, it was one-third the volume of the largest known tree, a giant sequoia named "General Sherman". The Quinault Lake Redcedar was 174 feet (53 m) tall with a diameter of 19.5 feet (5.9 m) at breast height. The "Quinault Lake Red Cedar" was destroyed by a series of storms in 2014 and 2016 and is now only a glorified stump. The fifth known largest was the Kalaloch Cedar in the Olympic National Park, at 12,370 cubic feet (350 m3), until it was destroyed by storm in March 2014.

A redcedar over 71 m (233 ft) tall, 4.5 m (15 ft) in diameter, and over 700 years old stood in Cathedral Grove on Vancouver IslandBritish Columbia, before it was set on fire and destroyed by vandals in 1972. That tree now lies in "Giant's Grave", a self-dug 'grave' created by the force of its own impact.

Uses

Timber

Canadian western redcedar cowl in the National Assembly for Wales

The soft red-brown timber has a tight, straight grain and few knots. It is valued for its distinct appearance, aroma, and its high natural resistance to decay, being extensively used for outdoor construction in the form of posts, decking, shingles, and siding. It is commonly used for the framing and longwood in lightweight sail boats and kayaks. In larger boats it is often used in sandwich construction between two layers of epoxy resin and/or fibreglass or similar products. Due to its light weight—390 to 400 kg/m3 (24 to 25 lb/cu ft) dried—it is about 30% lighter than common boat building woods, such as mahogany. For its weight it is quite strong but can be brittle. It glues well with epoxy resin or resorcinol adhesive.

The wood typically used as an insect-repelling closet lining and to make cedar chests is a different species, Juniperus virginiana (also known as red cedar).

Its light weight, strength, and dark, warm sound make it a popular choice for guitar soundboards.

Cultivation

Like its relative Thuja occidentalis and many other conifer species, Thuja plicata is grown as an ornamental tree, and for screens and hedges, throughout the world in gardens and parks. A wide variety of forms, sizes, and colours is available.

Cultivars

The following cultivars have gained the Royal Horticultural Society's Award of Garden Merit:

  • 'Atrovirens'
  • 'Aurea'
  • 'Stoneham gold'
  • ’Whipcord’
Other uses

Thujaplicin, a chemical substance, is found in mature trees and serves as a natural fungicide, thereby preventing the wood from rotting. This effect lasts around a century even after the tree is felled. However, thujaplicin is only found in older trees. Saplings that do not produce the chemical often rot at an early stage, causing some trees to grow with a somewhat hollow, rotten trunk.

It is also widely used throughout Europe and America for making beehive frames.

Role in indigenous societies

Klallam people and canoe, ca. 1914

Western redcedar has an extensive history of use by Native Americans of coastal Oregon to southeast Alaska. Some northwest coast tribes refer to themselves as "people of the redcedar" because of their extensive dependence on the tree for basic materials. The wood has been used for constructing housing and totem poles, and crafted into many objects, including masks, utensils, boxes, boards, instruments, canoes, vessels, houses, and ceremonial objects. Western Red Cedar is also associated with a long tradition of curing and cooking fish over the open fire. Roots and bark are used for baskets, bowls, ropes, clothing, blankets, and rings.

History

A huge number of archeological finds point to the continuous use of redcedar wood in native societies. Woodworking tools dating between 8000 and 5000 years ago, such as carved antlers, were discovered in shell middens at the Glenrose site, near Vancouver, British Columbia. In Yuquot, on the west coast of Vancouver Island, tools dating 4000 to 3000 years old have been found. The Musqueam site, also near Vancouver, yielded bark baskets woven in five different styles, along with ropes and ships dated to 3000 years ago. At Pitt Riveradzes and baskets were dated around 2900 years aol. Wooden artifacts 1000 years old were unearthed on the east coast of Vancouver Island.

Red cedar was used extensively wherever it was found along the northwest coast (British ColumbiaWashington state, Parts of Alaska). Evidence of this use is found in CMTs (Culturally Modified Trees) that are found throughout the coast. When First Nations people removed the bark from cedars, it left a scar - which is considered a CMT. Other types of harvest (for planks, tinder, and other uses) leave different types of evidence of cultural modification.

A legend amongst the Coast Salish peoples describes the origins of the western redcedar. In this legend, there was a generous man who gave the people whatever they needed. When the Great Spirit saw this, he declared that when the generous man died, a great redcedar tree will grow where he is buried, and that the cedar will be useful to all the people, providing its roots for baskets, bark for clothing, and wood for shelter.

Tools

The wood was worked primarily with the adze, which was preferred over all other tools, even ones introduced by colonizers. Alexander Walker, an ensign on the fur trade ship Captain Cook, reported that the indigenous peoples used an elbow adze, which they valued over tools brought by the Europeans, such as the saw or the axe, going so far as to modify traded tools back into an adze. Tools were generally made from stone, bone, obsidian, or a harder wood such as hemlock. A variety of hand mauls, wedges, chisels, and knives are also used.

Excavations done at Ozette, Washington turned up iron tools nearly 800 years old, far before European contact. When James Cook passed the area, he observed that almost all tools were made of iron. There has been speculation on the origin of these iron tools. Some theories include shipwrecks from East Asia or possible contact with iron-using cultures from Siberia, as hinted in the more advanced woodworking found in northern tribes such as the Tlingit.

Wood

A pole outside a six-post house at the University of British Columbia

Harvesting redcedars required some ceremony and included propitiation of the tree's spirits as well as those of the surrounding trees. In particular, many people specifically requested the tree and its brethren not to fall or drop heavy branches on the harvester, a situation which is mentioned in a number of different stories of people who were not sufficiently careful. Some professional loggers of Native American descent have mentioned that they offer quiet or silent propitiations to trees which they fell, following in this tradition.

Felling of large trees such as redcedar before the introduction of steel tools was a complex and time-consuming art. Typically the bark was removed around the base of the tree above the buttresses. Then some amount of cutting and splitting with stone adzes and mauls would be done, creating a wide triangular cut. The area above and below the cut would be covered with a mixture of wet moss and clay as a firebreak. Then the cut would be packed with tinder and small kindling and slowly burned. The process of cutting and burning would alternate until the tree was mostly penetrated through, and then careful tending of the fire would fell the tree in the best direction for handling. This process could take many days. Constant rotation of workers was involved to keep the fires burning through night and day, often in a remote and forbidding location.

Once the tree was felled, the work had only just begun, as it then had to be stripped and dragged down to shore. If the tree was to become canoes, then it would often be divided into sections and worked into rough canoe shapes before transport. If it were to be used for a totem pole or building materials, it would be towed in the round to the village. Many trees are still felled in this traditional manner for use as totem poles and canoes, particularly by artists who feel that using modern tools is detrimental to the traditional spirit of the art. Non-traditionalists simply buy redcedar logs or lumber at mills or lumber yards, a practice that is commonly followed by most working in smaller sizes such as for masks and staves.

Because felling required such an extraordinary amount of work, if only planks for housing were needed, these would be split from the living tree. The bark was stripped and saved, and two cuts were made at the ends of the planking. Then wedges would be pounded in along the sides and the planks slowly split off the side of the tree. Trees which have been so harvested are still visible in some places in the rainforest, with obvious chunks taken off of their sides. Such trees usually continue to grow perfectly well, since redcedar wood is resistant to decay. Planks are straightened by a variety of methods, including weighing them down with stones, lashing them together with rope, or forcing them between a line of stakes.

Illustration of women pulling bark from a tree, from Indian Legends of Vancouver Island by Alfred Carmichael

Redcedar wood is used to make huge monoxyla canoes in which the men went out to high sea to harpoon whales and conduct trade. One of those canoes, a 38-foot (12 m) craft dug out about a century ago, was bought in 1901 by Captain John Voss, an adventurer. He gave her the name of Tilikum ("Relative" in Chinook jargon), rigged her, and led her in a hectic three-year voyage from British Columbia to London.

Redcedar branches are very flexible and have good tensile strength. They were stripped and used as strong cords for fishing line, rope cores, twine, and other purposes where bark cord was not strong enough or might fray. Both the branches and bark rope have been replaced by modern fiber and nylon cordage among the aboriginal northwest coast peoples, though the bark is still in use for the other purposes mentioned above.

Bark

At the right time of year, the bark is easily removed from live trees in long strips. It is harvested for use in making mats, rope and cordage, basketry, rain hats, clothing, and other soft goods. The harvesting of bark must be done with care, as stripping too much bark will kill the tree. To prevent this, the harvester usually only harvests from trees which have not been stripped before. After harvesting, the tree is not used for bark again, although it may later be felled for wood. Stripping bark is usually started with a series of cuts at the base of the tree above any buttresses, after which the bark is peeled upwards. To remove bark high up, a pair of platforms strung on rope around the tree are used and the harvester climbs by alternating between them for support. Since redcedars lose their lower branches as all tall trees do in the rainforest, the harvester may climb 10 m (33 ft) or more into the tree by this method. The harvested bark is folded and carried in backpacks. It can be stored for quite some time as mold does not grow on it, and is moistened before unfolding and working. It is then split lengthwise into the required width and woven or twisted into shape. Bark harvesting was mostly done by women, despite the danger of climbing 10 meters in the air, because they were the primary makers of bark goods.

Today bark rope making is a lost art in many communities, although it is still practiced for decoration or art in a few places. Other uses of bark are still common for artistic or practical purposes. In recent years there has been a revival of cedar weaving in some communities, and along with it, new forms of cedar bark products. For example, in some recent weddings cedar roses are used to decorate the tables.

Legal status

Western red cedar is export-restricted in the United States under the Export Administration Regulations.

Health and safety

Western red cedar is highly allergenic and woodworkers or loggers who work with it may have adverse reactions, including the development of occupational asthma, exacerbation of existing asthma, reduction of lung function, and eye irritation. Approximately 5% of workers are allergic to western red cedar. The US Occupational Safety and Health Administration has set a permissible exposure limit for red cedar dust of 2.5 mg/m3 as a time-weighted average over 8 hours.