Tsuga chinensis
Encyclopedia
Tsuga chinensis, commonly referred to as the Taiwan or Chinese Hemlock, or in Chinese as Tieshan , is a coniferous tree species native to China
, Taiwan
, Tibet
and Vietnam
. The tree is quite variable and has many recognised varieties, though some are also maintained to be separate species by certain authorities. The tree was recently discovered in the mountains of northern Vietnam, making that the southernmost extension of its range.
that is a blackish brown in colour. The scaly bark has irregular longitudinal breaks, and lenticel
s that are very inconspicuous. The outer bark is about 6 mm thick with alternating tiered layers of pale yellowish brown corky bark, and brown lignified fibrous bark. The newly formed periderm is a purplish red. The inner bark is about 4 to 5 mm thick and pale reddish brown in colour. It is fibrous in texture with minute, almost inconspicuous sclereid, or stone cell groups. The cambium
as well as the newly formed phloem
are nearly inconspicuous. Freshly cut wood is a pale yellowish white with inconspicuous wood rays.
The branchlets that have leaf-cushions. The leaves
are arranged spirally in a manner more or less 2-ranked. They are linear and flat in shape and olive green in colour. The upper side of the leaf is grooved and keeled, while the underside has 2 white stomatic bands. The apex of the leaves are emerginate and they measure 16 to 20 mm long. The petiole
s are crooked. The foliage is very similar to that of T. heterophylla, but T. chinensis has nodding shoots and the stomatic bands are paler and more sparse. Also the colour above is a paler yellowish-green. The stamenate flower
s appear singly on one-year old shoots, or in groups of 1 to 5 on two-year old shoots. They are a dull purple in colour and measure about 8 mm. The pistillate flowers are terminal on a very short shoot. They nod, are rosy-purple and are about 6 mm in length. The mature cones are green, later turning to red-brown, long-ovoid in shape and measure 2 to 2.5 cm long by about 1 cm wide. They are pendulous and the cone scales are large and suborbicular with longitudinal streaks. The bract
s are small and 2 lobed at the apex. The seeds are winged and measure about 7 mm long with the wing included.
and continues east into China
, north to southern Shanxi
province and south to Taiwan
, Guangdong
province and the north of Ha Giang
province in northern Vietnam
. In the very south of their range they are only found high in the mountains. For example in Vietnam the tree is only found in mountains 1,300 to 1,700 metres above sea level. In China it is present at altitudes of 1,000 to 3,500 metres in the following provinces: Anhui
, Fujian
, southern Gansu
, Guangdong
, Guangxi
, northern Guizhou
, western Henan
, western Hubei
, Hunan
, Jiangxi
, southern Shaanxi
, Sichuan
, Xizang, Yunnan
, and Zhejiang
. This comprises the southern half of the country with a few population farther north. It is found primarily in mixed forests near river basins and in mountains and valleys. In Taiwan it is found mainly in Nantou
and Taoyuan Counties at heights of 1700 to 3500 metres in mixed broadleaf forests. It can be found in Taiwans's Yushan National Park
and Lalashan Preserve, as well as in China's Hailuogou Glacier Park in Sichuan
province.
making, and as a support in mines
. The bark is high in tannin
s, which is often extracted and used as a dye
. The trunk
is used as a source of resin
. In addition, the roots, trunk, and branches are all used in the production of aromatic oils due to their pleasing scent.
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, Tibet
Tibet
Tibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...
and Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...
. The tree is quite variable and has many recognised varieties, though some are also maintained to be separate species by certain authorities. The tree was recently discovered in the mountains of northern Vietnam, making that the southernmost extension of its range.
Description
T. chinensis is a large tree with barkBark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
that is a blackish brown in colour. The scaly bark has irregular longitudinal breaks, and lenticel
Lenticel
A lenticel is an airy aggregation of cells within the structural surfaces of the stems, roots, and other parts of vascular plants. It functions as a pore, providing a medium for the direct exchange of gasses between the internal tissues and atmosphere, thereby bypassing the periderm, which would...
s that are very inconspicuous. The outer bark is about 6 mm thick with alternating tiered layers of pale yellowish brown corky bark, and brown lignified fibrous bark. The newly formed periderm is a purplish red. The inner bark is about 4 to 5 mm thick and pale reddish brown in colour. It is fibrous in texture with minute, almost inconspicuous sclereid, or stone cell groups. The cambium
Cork cambium
Cork cambium is a tissue found in many vascular plants as part of the periderm. The cork cambium is a lateral meristem and is responsible for secondary growth that replaces the epidermis in roots and stems...
as well as the newly formed phloem
Phloem
In vascular plants, phloem is the living tissue that carries organic nutrients , in particular, glucose, a sugar, to all parts of the plant where needed. In trees, the phloem is the innermost layer of the bark, hence the name, derived from the Greek word "bark"...
are nearly inconspicuous. Freshly cut wood is a pale yellowish white with inconspicuous wood rays.
The branchlets that have leaf-cushions. The leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
are arranged spirally in a manner more or less 2-ranked. They are linear and flat in shape and olive green in colour. The upper side of the leaf is grooved and keeled, while the underside has 2 white stomatic bands. The apex of the leaves are emerginate and they measure 16 to 20 mm long. The petiole
Petiole (botany)
In botany, the petiole is the stalk attaching the leaf blade to the stem. The petiole usually has the same internal structure as the stem. Outgrowths appearing on each side of the petiole are called stipules. Leaves lacking a petiole are called sessile, or clasping when they partly surround the...
s are crooked. The foliage is very similar to that of T. heterophylla, but T. chinensis has nodding shoots and the stomatic bands are paler and more sparse. Also the colour above is a paler yellowish-green. The stamenate flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s appear singly on one-year old shoots, or in groups of 1 to 5 on two-year old shoots. They are a dull purple in colour and measure about 8 mm. The pistillate flowers are terminal on a very short shoot. They nod, are rosy-purple and are about 6 mm in length. The mature cones are green, later turning to red-brown, long-ovoid in shape and measure 2 to 2.5 cm long by about 1 cm wide. They are pendulous and the cone scales are large and suborbicular with longitudinal streaks. The bract
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale. Bracts are often different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture...
s are small and 2 lobed at the apex. The seeds are winged and measure about 7 mm long with the wing included.
Range and Habitat
The range of T. chinensis begins in the west in TibetTibet
Tibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...
and continues east into China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
, north to southern Shanxi
Shanxi
' is a province in Northern China. Its one-character abbreviation is "晋" , after the state of Jin that existed here during the Spring and Autumn Period....
province and south to Taiwan
Taiwan
Taiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
, Guangdong
Guangdong
Guangdong is a province on the South China Sea coast of the People's Republic of China. The province was previously often written with the alternative English name Kwangtung Province...
province and the north of Ha Giang
Ha Giang
Hà Giang is a town in northeastern Vietnam. It is the capital of Ha Giang province. The town has an area of 168.7 km² and population of 40,000 inhabitants.-Administration:Hà Giang is divided into one city and ten districts:Bắc MêBắc Quang...
province in northern Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...
. In the very south of their range they are only found high in the mountains. For example in Vietnam the tree is only found in mountains 1,300 to 1,700 metres above sea level. In China it is present at altitudes of 1,000 to 3,500 metres in the following provinces: Anhui
Anhui
Anhui is a province in the People's Republic of China. Located in eastern China across the basins of the Yangtze River and the Huai River, it borders Jiangsu to the east, Zhejiang to the southeast, Jiangxi to the south, Hubei to the southwest, Henan to the northwest, and Shandong for a tiny...
, Fujian
Fujian
' , formerly romanised as Fukien or Huguing or Foukien, is a province on the southeast coast of mainland China. Fujian is bordered by Zhejiang to the north, Jiangxi to the west, and Guangdong to the south. Taiwan lies to the east, across the Taiwan Strait...
, southern Gansu
Gansu
' is a province located in the northwest of the People's Republic of China.It lies between the Tibetan and Huangtu plateaus, and borders Mongolia, Inner Mongolia, and Ningxia to the north, Xinjiang and Qinghai to the west, Sichuan to the south, and Shaanxi to the east...
, Guangdong
Guangdong
Guangdong is a province on the South China Sea coast of the People's Republic of China. The province was previously often written with the alternative English name Kwangtung Province...
, Guangxi
Guangxi
Guangxi, formerly romanized Kwangsi, is a province of southern China along its border with Vietnam. In 1958, it became the Guangxi Zhuang Autonomous Region of the People's Republic of China, a region with special privileges created specifically for the Zhuang people.Guangxi's location, in...
, northern Guizhou
Guizhou
' is a province of the People's Republic of China located in the southwestern part of the country. Its provincial capital city is Guiyang.- History :...
, western Henan
Henan
Henan , is a province of the People's Republic of China, located in the central part of the country. Its one-character abbreviation is "豫" , named after Yuzhou , a Han Dynasty state that included parts of Henan...
, western Hubei
Hubei
' Hupeh) is a province in Central China. The name of the province means "north of the lake", referring to its position north of Lake Dongting...
, Hunan
Hunan
' is a province of South-Central China, located to the south of the middle reaches of the Yangtze River and south of Lake Dongting...
, Jiangxi
Jiangxi
' is a southern province in the People's Republic of China. Spanning from the banks of the Yangtze River in the north into hillier areas in the south, it shares a border with Anhui to the north, Zhejiang to the northeast, Fujian to the east, Guangdong to the south, Hunan to the west, and Hubei to...
, southern Shaanxi
Shaanxi
' is a province in the central part of Mainland China, and it includes portions of the Loess Plateau on the middle reaches of the Yellow River in addition to the Qinling Mountains across the southern part of this province...
, Sichuan
Sichuan
' , known formerly in the West by its postal map spellings of Szechwan or Szechuan is a province in Southwest China with its capital in Chengdu...
, Xizang, Yunnan
Yunnan
Yunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
, and Zhejiang
Zhejiang
Zhejiang is an eastern coastal province of the People's Republic of China. The word Zhejiang was the old name of the Qiantang River, which passes through Hangzhou, the provincial capital...
. This comprises the southern half of the country with a few population farther north. It is found primarily in mixed forests near river basins and in mountains and valleys. In Taiwan it is found mainly in Nantou
Nantou
Nantou may refer to:* Nantou County - central Taiwan, Republic of China* Nantou City - a city in Nantou County, Taiwan Province, Republic of China...
and Taoyuan Counties at heights of 1700 to 3500 metres in mixed broadleaf forests. It can be found in Taiwans's Yushan National Park
Yushan National Park
Yushan National Park is one of the seven national parks in Taiwan and was named after the summit Yushan, the highest peak of the park. The Park covers a total of 105,490 hectares including large sections of the Central Mountain Range. The Park contains over thirty peaks more than 3,000 meters in...
and Lalashan Preserve, as well as in China's Hailuogou Glacier Park in Sichuan
Sichuan
' , known formerly in the West by its postal map spellings of Szechwan or Szechuan is a province in Southwest China with its capital in Chengdu...
province.
Taxonomy
There are a number of varieties of T. chinensis, though there is much dispute over which are valid and whether some constitute distinct species or not. All in all there are six varieties, though not all are accepted universally. These are:- T. c. var. chinensis is the type variety and occurs across most of the range in mainland ChinaMainland ChinaMainland China, the Chinese mainland or simply the mainland, is a geopolitical term that refers to the area under the jurisdiction of the People's Republic of China . According to the Taipei-based Mainland Affairs Council, the term excludes the PRC Special Administrative Regions of Hong Kong and...
and TibetTibetTibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...
. Its seed scales are pentagonal-ovate, subsquare, or suborbicular, while its branchlets are 1 mm in diameter and grey to yellow-grey in colour. The cones are ovoid and 1.5 to 2.5 cm tall by 1.2 to 1.6 cm wide. - T. c. var. formosana is the variety that occurs exclusively in TaiwanTaiwanTaiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
. Aljos Farjon, a conifer expert from the Royal Botanic GardensRoyal Botanic Gardens, KewThe Royal Botanic Gardens, Kew, usually referred to as Kew Gardens, is 121 hectares of gardens and botanical glasshouses between Richmond and Kew in southwest London, England. "The Royal Botanic Gardens, Kew" and the brand name "Kew" are also used as umbrella terms for the institution that runs...
at KewKewKew is a place in the London Borough of Richmond upon Thames in South West London. Kew is best known for being the location of the Royal Botanic Gardens, now a World Heritage Site, which includes Kew Palace...
, considers this variety identical with the type, but according to Raven and Wu it differs from the type by having seed scales which are compressed orbicular to nearly semiorbicular. Otherwise, however, it is like the type. - T. c. var. patens is found only in western HubeiHubei' Hupeh) is a province in Central China. The name of the province means "north of the lake", referring to its position north of Lake Dongting...
province on Changyang Xian. It differs in having brownish yellow to brown branchlets, which are between to 0.5 to 1 mm longer in diameter than the type. The seed cones also differ in being slightly larger, ovoid-globose in shape, and with seed scales that are smooth, shiny and almost square. This variety is recognized by Raven and Wu. - T. c. var. forrestii is treated as a separate species, namely T. forrestii, by some authorities. The cones are larger, more slender and narrow-ovoid to ovoid-cylindric. The branchlets are slightly thicker, while the seed scales are narrowly ovate or oblong with the exposed part striate and glabrous with a thickened margin. Regardless of its taxonomic status, it is considered threatened by the IUCN. It occurs only in northeast GuizhouGuizhou' is a province of the People's Republic of China located in the southwestern part of the country. Its provincial capital city is Guiyang.- History :...
, southwest SichuanSichuan' , known formerly in the West by its postal map spellings of Szechwan or Szechuan is a province in Southwest China with its capital in Chengdu...
and northwest YunnanYunnanYunnan is a province of the People's Republic of China, located in the far southwest of the country spanning approximately and with a population of 45.7 million . The capital of the province is Kunming. The province borders Burma, Laos, and Vietnam.Yunnan is situated in a mountainous area, with...
. - T. c. var. robusta is probably the most universally recognised of the varieties. It is present in western HubeiHubei' Hupeh) is a province in Central China. The name of the province means "north of the lake", referring to its position north of Lake Dongting...
and western SichuanSichuan' , known formerly in the West by its postal map spellings of Szechwan or Szechuan is a province in Southwest China with its capital in Chengdu...
. It again exhibits the thicker branchlets and larger cones, but the cones are stout and shortly cylindric. Also, the seed scales are square-orbicular with the exposed part being pubescent and the margin not thickened. In addition, the bracts are cuspidate at the apex. - T. c. var. oblongisquamata is considered a separate species by Raven and Wu, namely T. oblongisquamata, but as a variety by Farjon. It occurs in the northern part of the range, namely in southern GansuGansu' is a province located in the northwest of the People's Republic of China.It lies between the Tibetan and Huangtu plateaus, and borders Mongolia, Inner Mongolia, and Ningxia to the north, Xinjiang and Qinghai to the west, Sichuan to the south, and Shaanxi to the east...
, western Hubei and northwest Sichuan. It differs most sharply in lacking visible stomatic bands beneath the leaves. Otherwise the seed scales are more loosely arranged and loosely elliptic in shape, being nearly twice as long as they are wide.
Uses
The timber obtained from T. chinensis is used in construction, furnitureFurniture
Furniture is the mass noun for the movable objects intended to support various human activities such as seating and sleeping in beds, to hold objects at a convenient height for work using horizontal surfaces above the ground, or to store things...
making, and as a support in mines
Mining
Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...
. The bark is high in tannin
Tannin
A tannin is an astringent, bitter plant polyphenolic compound that binds to and precipitates proteins and various other organic compounds including amino acids and alkaloids.The term tannin refers to the use of...
s, which is often extracted and used as a dye
Dye
A dye is a colored substance that has an affinity to the substrate to which it is being applied. The dye is generally applied in an aqueous solution, and requires a mordant to improve the fastness of the dye on the fiber....
. The trunk
Trunk (botany)
In botany, trunk refers to the main wooden axis of a tree that supports the branches and is supported by and directly attached to the roots. The trunk is covered by the bark, which is an important diagnostic feature in tree identification, and which often differs markedly from the bottom of the...
is used as a source of resin
Resin
Resin in the most specific use of the term is a hydrocarbon secretion of many plants, particularly coniferous trees. Resins are valued for their chemical properties and associated uses, such as the production of varnishes, adhesives, and food glazing agents; as an important source of raw materials...
. In addition, the roots, trunk, and branches are all used in the production of aromatic oils due to their pleasing scent.