|
|
| Line 1: |
Line 1: |
| − | {{ce}}{{Images OK}}{{Approved}}
| |
| − | {{Taxobox
| |
| − | | name = Willow
| |
| − | | image = Willow.jpg
| |
| − | | image_width = 270px
| |
| − | | image_caption = ''Salix × sepulcralis'' - weeping willow
| |
| − | | regnum = [[Plant]]ae
| |
| − | | divisio = [[Flowering plant|Magnoliophyta]]
| |
| − | | classis = [[Dicotyledon|Magnoliopsida]]
| |
| − | | ordo = [[Malpighiales]]
| |
| − | | familia = [[Salicaceae]]
| |
| − | | genus = '''''Salix''''' [[Carolus Linnaeus|L.]]
| |
| − | | subdivision_ranks = Species
| |
| − | | subdivision =
| |
| − | About 400 species
| |
| − | }}
| |
| − | '''Willows''' is the common name for any of the [[deciduous]] [[tree]]s and [[shrub]]s comprising the [[genus]] '''''Salix''''' of the [[flowering plant]] family Salicaceae, characterized by [[flower]]s borne in [[catkin]]s, tiny [[seed]]s with long, silky hairs, and alternate [[leaf|leaves]]. The word willow also is used for the strong, lightweight wood of these plants, which has commercial use. While willow is the common name in general for plants of this genus, and most species have willow as part of their common name, some narrow-leaved shrub species are called '''osier''', and some broader-leaved species are called '''sallow'''. (The latter name is derived from the [[Latin]] word ''salix'', for "willow.") This article will use the word willow as the general name for members of this genus.
| |
| | | | |
| − | There are about 400 species of willow. Willows are found primarily on moist [[soil]]s in cold and temperate regions of the [[Northern Hemisphere]]. Some willows (particularly [[arctic]] and [[alpine climate|alpine]] species), are low-growing or creeping shrubs; for example the [[dwarf willow]] ''(Salix herbacea)'' rarely exceeds 6 centimeters in height, though spreading widely across the ground.
| |
| − |
| |
| − | Willows are very cross-fertile and numerous [[Hybrid (biology)|hybrid]]s occur, both naturally and in cultivation. A well known example is the weeping willow ''(Salix × sepulcralis)'', very widely planted as an [[ornamental plant|ornamental tree]], which is a hybrid of a [[China|Chinese]] species and a [[Europe]]an species –[[Salix babylonica|Peking willow]] and [[white willow]].
| |
| − |
| |
| − | Willows provide important ecological functions for erosion control along watercourses, and habitat and food for animals. For people, in addition to aesthetic and shade uses, the wood provides an important source of timber and the plant has a long history of medicinal use as the source of [[salicylic acid]], the precursor to [[aspirin]].
| |
| − |
| |
| − | ==Description==
| |
| − | [[Image:PICT3750small.jpg|thumb|right|170px|Willow leaves ''(Salix × sepulcralis)'']]
| |
| − | Willows all have slender branches; large, fibrous, often [[stolon]]iferous roots; abundant watery sap; [[bark]] that is heavily charged with [[salicylic acid]]; and soft, usually pliant, tough wood. The [[root]]s are remarkable for their toughness, size, and tenacity of life, and roots readily grow from aerial parts of the plant.
| |
| − |
| |
| − | The [[leaf|leaves]] are typically elongated but may also be round to oval, frequently with a serrated margin. All the buds are lateral; no absolutely terminal bud is ever formed. The buds are covered by a single scale, enclosing at its base two very small opposite buds, alternately arranged, with two, small, scale-like, fugacious, opposite leaves. The leaves are alternate, except the first pair, which fall when about an inch long. They are simple, feather-veined, and typically linear-lanceolate. Usually they are serrate, rounded at base, acute, or acuminate. The leaf petioles are short, the stipules often very conspicuous, looking like tiny round leaves and sometimes remaining for half the summer. On some species, however, they are small, inconspicuous, and fugacious (soon falling). In color, the leaves show a great variety of greens, ranging from yellowish to bluish.
| |
| − |
| |
| − | ===Flowers===
| |
| − | [[Image:Willow catkin 1 aka.jpg|thumb|right|170px|Willow catkin ''([[Salix discolor]])'']]
| |
| − | Willows are [[plant sexuality|dioecious]] with male and female [[flower]]s appearing as [[catkin]]s on different plants; the catkins are produced early in the spring, often before the leaves, or as the new leaves open.
| |
| − |
| |
| − | The staminate (male) flowers are without either [[Calyx (botany)|calyx]] or [[Corolla (flower)|corolla]]; they consist simply of stamens, varying in number from two to ten, accompanied by a nectariferous gland and inserted on the base of a scale, which is itself borne on the rachis of a drooping raceme called a catkin, or ament. This scale is oval and entire and very hairy. The anthers are rose colored in the bud but orange or purple after the flower opens, they are two-celled and the cells open longitudinally. The filaments are threadlike, usually pale yellow, and often hairy.
| |
| − |
| |
| − | The pistillate (female) flowers are also without calyx or corolla; and consist of a single ovary accompanied by a small flat nectar gland and inserted on the base of a scale, which is likewise borne on the rachis of a catkin. The ovary is one-celled, the style two-lobed, and the ovules numerous.
| |
| − |
| |
| − | ===Fruit===
| |
| − | The [[fruit]] is a small, one-celled, two-valved, cylindrical beaked [[capsule (fruit)|capsule]] containing numerous tiny (0.1 mm) [[seed]]s. The seeds are furnished with long, silky, white hairs, which allow the fruit to be widely dispersed by the wind.
| |
| − |
| |
| − | ==Cultivation==
| |
| − | Almost all willows take root very readily from cuttings or where broken branches lie on the ground. There are a few exceptions, including the [[goat willow]] and [[peachleaf willow]].
| |
| − |
| |
| − | One famous example of such growth from cuttings involves the poet [[Alexander Pope]], who begged a twig from a parcel tied with twigs sent from Spain to Lady Suffolk. This twig was planted and thrived, and legend has it that all of England's weeping willows are descended from this first one (Hone 1826).
| |
| − |
| |
| − | Willows are often planted on the borders of streams so that their interlacing roots may protect the bank against the action of the water. Frequently, the roots are much larger than the stem that grows from them.
| |
| − |
| |
| − | ==Species==
| |
| − | There are around 400 species in the genus ''Salix'' (Mabberley 1997), including:
| |
| − | {{col-begin}}
| |
| − | {{col-2}}
| |
| − |
| |
| − | ''[[Salix acutifolia]]'' - [[violet willow]]<br/>
| |
| − | ''[[Salix alaxensis]]'' - [[Alaska willow]]<br/>
| |
| − | ''[[Salix alba]]'' - [[white willow]]<br/>
| |
| − | ''[[Salix alpina]]'' - [[alpine willow]]<br/>
| |
| − | ''[[Salix amygdaloides]]'' - [[peachleaf willow]]<br/>
| |
| − | ''[[Salix arbuscula]]'' - [[mountain willow]]<br/>
| |
| − | ''[[Salix arbusculoides]]'' - [[littletree willow]]<br/>
| |
| − | ''[[Salix arctica]]'' - [[arctic willow]]<br/>
| |
| − | ''[[Salix atrocinerea]]''<br/>
| |
| − | ''[[Salix aurita]]'' - [[eared willow]]<br/>
| |
| − | ''[[Salix babylonica]]'' - [[Peking willow]]<br/>
| |
| − | ''[[Salix bakko]]''<br/>
| |
| − | ''[[Salix barrattiana]]'' - [[Barratt's willow]]<br/>
| |
| − | ''[[Salix bebbiana]]'' - [[beaked willow]]<br/>
| |
| − | ''[[Salix boothii]]'' - [[Booth willow]]<br/>
| |
| − | ''[[Salix bouffordii]]''<br/>
| |
| − | ''[[Salix brachycarpa]]'' - [[barren-ground willow]]<br/>
| |
| − | ''[[Salix cacuminis]]''<br/>
| |
| − | ''[[Salix canariensis]]''<br/>
| |
| − | ''[[Salix candida]]'' - [[sage willow]]<br/>
| |
| − | ''[[Salix caprea]]'' - [[goat willow]]<br/>
| |
| − | ''[[Salix caroliniana]]'' - [[coastal plain willow]]<br/>
| |
| − | ''[[Salix chaenomeloides]]''<br/>
| |
| − | ''[[Salix chilensis]]''<br/>
| |
| − | ''[[Salix cinerea]]'' - [[grey sallow]]<br/>
| |
| − | ''[[Salix cordata]]'' - heartleaf or sand dune willow<br/>
| |
| − | ''[[Salix daphnoides]]'' <br/>
| |
| − | ''[[Salix delnortensis]]'' <br/>
| |
| − | ''[[Salix discolor]]'' - [[pussy willow]]<br/>
| |
| − | ''[[Salix eastwoodiae]]'' - [[Eastwood's willow]]<br/>
| |
| − | ''[[Salix eleagnos]]''<br/>
| |
| − | ''[[Salix eriocarpa]]''<br/>
| |
| − | ''[[Salix eriocephala]]'' - heartleaf willow<br/>
| |
| − | ''[[Salix excelsa]]''<br/>
| |
| − | ''[[Salix exigua]]'' - [[sandbar willow]]<br/>
| |
| − | ''[[Salix foetida]]'' <br/>
| |
| − | ''[[Salix fragilis]]'' - [[crack willow]]<br/>
| |
| − | ''[[Salix futura]]''<br/>
| |
| − | ''[[Salix geyeriana]]''<br/>
| |
| − | ''[[Salix gilgiana]]''<br/>
| |
| − | ''[[Salix glauca]]''<br/>
| |
| − | ''[[Salix gooddingii]]'' - [[Goodding willow]]<br/>
| |
| − | ''[[Salix gracilistyla]]''<br/>
| |
| − | ''[[Salix hainanica]]'' - [[Hainan willow]]<br/>
| |
| − | ''[[Salix helvetica]]'' - [[Swiss willow]]<br/>
| |
| − | ''[[Salix herbacea]]'' - [[dwarf willow]]<br/>
| |
| − | ''[[Salix hirsuta]]''<br/>
| |
| − | ''[[Salix hookeriana]]'' - [[Hooker's willow]]<br/>
| |
| − | ''[[Salix hultenii]]''<br/>
| |
| − | ''[[Salix humboldtiana]]'' - [[Chile willow]]<br/>
| |
| − | ''[[Salix humilis]]'' - [[upland willow]]<br/>
| |
| − | ''[[Salix integra]]''<br/>
| |
| − | ''[[Salix interior]]''<br/>
| |
| − | ''[[Salix japonica]]''<br/>
| |
| − | ''[[Salix jessoensis]]''<br/>
| |
| − | ''[[Salix koriyanagi]]''<br/>
| |
| − | {{col-2}}
| |
| − | ''[[Salix kusanoi]]''<br/>
| |
| − | ''[[Salix lanata]]'' - [[woolly willow]]<br/>
| |
| − | ''[[Salix lapponum]]'' - [[downy willow]]<br/>
| |
| − | ''[[Salix lasiandra]]'' - [[Pacific willow]]<br/>
| |
| − | ''[[Salix lasiolepis]]'' - [[Arroyo willow]]<br/>
| |
| − | ''[[Salix lucida]]'' - [[shining willow]]<br/>
| |
| − | ''[[Salix magnifica]]''<br/>
| |
| − | ''[[Salix matsudana]]'' - [[Chinese willow]]<br/>
| |
| − | ''[[Salix miyabeana]]''<br/>
| |
| − | ''[[Salix mucronata]]''<br/>
| |
| − | ''[[Salix myrtilloides]]'' - [[swamp sillow]]<br/>
| |
| − | ''[[Salix myrsinifolia]]'' - [[dark-leaved willow]]<br/>
| |
| − | ''[[Salix myrsinites]]'' - [[whortle-leaved willow]]<br/>
| |
| − | ''[[Salix nakamurana]]''<br/>
| |
| − | ''[[Salix nigra]]'' - [[black willow]]<br/>
| |
| − | ''[[Salix pedicellaris]]'' - [[bog willow]]<br/>
| |
| − | ''[[Salix pentandra]]'' - [[bay willow]]<br/>
| |
| − | ''[[Salix petiolaris]]'' - [[slender willow]]<br/>
| |
| − | ''[[Salix phylicifolia]]'' - [[tea-leaved willow]]<br/>
| |
| − | ''[[Salix planifolia]]''- [[planeleaf willow]]<br/>
| |
| − | ''[[Salix polaris]]'' - [[polar willow]]<br/>
| |
| − | ''[[Salix pseudo-argentea]]''<br/>
| |
| − | ''[[Salix purpurea]]'' - [[purple willow]]<br/>
| |
| − | ''[[Salix pyrifolia]]'' - [[balsam willow]]<br/>
| |
| − | ''[[Salix reinii]]''<br/>
| |
| − | ''[[Salix repens]]'' - [[creeping willow]]<br/>
| |
| − | ''[[Salix reticulata]]'' - [[net-leaved willow]]<br/>
| |
| − | ''[[Salix retusa]]''<br/>
| |
| − | ''[[Salix rorida]]''<br/>
| |
| − | ''[[Salix rosmarinifolia]]'' - [[rosemary-leaved willow]]<br/>
| |
| − | ''[[Salix rupifraga]]''<br/>
| |
| − | ''[[Salix salicicola]]''<br/>
| |
| − | ''[[Salix schwerinii]]''<br/>
| |
| − | ''[[Salix scouleriana]]'' - [[Scouler's willow]]<br/>
| |
| − | ''[[Salix sericea]]'' - [[silky willow]]<br/>
| |
| − | ''[[Salix serissaefolia]]''<br/>
| |
| − | ''[[Salix serissima]]'' - [[autumn willow]]<br/>
| |
| − | ''[[Salix shiraii]]''<br/>
| |
| − | ''[[Salix sieboldiana]]''<br/>
| |
| − | ''[[Salix sitchensis]]'' - [[Sitka willow]]<br/>
| |
| − | ''[[Salix subfragilis]]''<br/>
| |
| − | ''[[Salix subopposita]]''<br/>
| |
| − | ''[[Salix taraikensis]]''<br/>
| |
| − | ''[[Salix tetrasperma]]''<br/>
| |
| − | ''[[Salix thorelii]]''<br/>
| |
| − | ''[[Salix triandra]]'' - [[almond willow]]<br/>
| |
| − | ''[[Salix udensis]]''<br/>
| |
| − | ''[[Salix viminalis]]'' - [[common osier]]<br/>
| |
| − | ''[[Salix vulpina]]''<br/>
| |
| − | ''[[Salix waldsteiniana]]''<br/>
| |
| − | ''[[Salix wallichiana]]''<br/>
| |
| − | ''[[Salix wilmsii]]''<br/>
| |
| − | ''[[Salix woodii]]''<br/>
| |
| − | ''[[Salix yezoalpina]]''<br/>
| |
| − | ''[[Salix yoshinoi]]''<br/>
| |
| − | {{col-end}}
| |
| − |
| |
| − | ==Importance==
| |
| − | ===Ecological===
| |
| − | Willows are valuable for erosion control along watercourses. A number of willow species were widely planted in Australia for this purpose. They are now regarded as an invasive [[weed]] and many [[Catchment Management Authority|catchment management authorities]] are removing them to be replaced with native trees (Cremer 2003; AWWMWG 1998).
| |
| − |
| |
| − | Willows are used as food plants by the [[larva]]e of some [[Lepidoptera]] species, and the seeds are consumed by birds. Willow trees produce a modest amount of [[nectar]] that bees can make honey from, and are especially valued as a source of [[pollen]] for [[bee]]s.
| |
| − |
| |
| − | ===Medicinal===
| |
| − | The leaves and bark of the willow tree have been mentioned in ancient medicinal texts from [[Assyria]], [[Sumer]], and [[Ancient Egypt|Egypt]] as a remedy for aches and [[fever]] (Breasted 2007; Nobel 2008) and the [[Ancient Greece|Ancient Greek]] physician [[Hippocrates]] wrote about its medicinal properties in the [[5th century B.C.E.]]. [[Indigenous peoples of the Americas|Native Americans]] across the American continent relied on it as a staple of their medical treatments. This is because they contain [[salicylic acid]], the precursor to [[aspirin]].
| |
| − |
| |
| − | In 1763, the medicinal properties of willow were observed by the [[Reverend Edward Stone]] in England. He notified the [[Royal Society]] who published his findings. The active extract of the bark, called [[salicin]], was isolated to its crystalline form in 1828 by [[Henri Leroux]], a French pharmacist, and [[Raffaele Piria]], an Italian chemist, who then succeeded in separating out the acid in its pure state. Salicin is acidic when in a [[saturation (chemistry)|saturated solution]] in water (''p''H = 2.4), and is called [[salicylic acid]] for that reason.
| |
| − |
| |
| − | In 1897, [[Felix Hoffmann]] created a synthetically altered version of salicin (in his case derived from the ''[[Spiraea]]'' plant), which caused less digestive upset than pure salicylic acid. The new drug, formally ''[[Acetylsalicylic acid]]'', was named [[aspirin]] by Hoffmann's employer [[Bayer|Bayer AG]]. This gave rise to the hugely important class of drugs known as [[NSAIDs|non-steroidal anti-inflammatory drugs]] (NSAIDs).
| |
| − |
| |
| − | ===Other uses===
| |
| − | [[Image:Weeping Willow.jpg|thumb|right|240px|Weeping willow ''(Salix × sepulcralis)'' in [[Auckland]], [[New Zealand]]]]
| |
| − | Willows are popular as ornamental trees and for shade. For example, the weeping willows, with their long, drooping branches are popular for such purposes. They may be used as hedges and for windbreaks. The catkins also are popular in arrangements for display.
| |
| − |
| |
| − | The strong, but soft and pliant wood is used for a number of purposes as timber, including making boxes, crates, wicker furniture, [[broom]]s, [[cricket bat]]s (grown from certain strains of [[white willow]]), cradle boards, [[chair]]s and other furniture, [[doll]]s, [[willow flute|flute]]s, [[Pole (object)|pole]]s, [[sweat lodge]]s, [[toy]]s, turnery, tool handles, [[veneer]], [[wand]]s, [[whistle]]s, and boats. The wood also is used for fuel and charcoal. Other wood-derived products include [[paper]], [[rope]], and using the shoots for [[basket weaving]], [[fish]] traps, and wattle [[fence]]s, and willows are used for [[tannin]].
| |
| − |
| |
| − | Willow bark contains [[auxin]]s: plant growth hormones, especially those used for rooting new cuttings. The bark can even be used to make a simple extract that will promote cutting growth.
| |
| − |
| |
| − | [[Image:Li Di, Homeward Oxherds in Wind and Rain.jpg|thumb|right|240px|Willow tree in a painting by Chinese artist Li Di, 12th century, [[Song Dynasty]]]]
| |
| − | The willow is a famous subject in many East Asian nations' cultures, particularly painting (pen and ink) in China and Japan.
| |
| − |
| |
| − | As one of the "[[Four Species]]," the willow is used in a ceremony on the [[Judaism|Jewish]] holiday of [[Sukkot]]. Also the willow is one of the [[nine sacred trees]] mentioned in [[wicca]] and [[witchcraft]], with several magical uses.
| |
| − |
| |
| − | ==Pictures==
| |
| − | <gallery>
| |
| − | Image:Salix herbacea.jpg|Dwarf willow ''(Salix herbacea)'', [[Sweden]]
| |
| − | Image:Willow catkin 2 aka.jpg|Sallow catkin<br />''([[Salix caprea]])''
| |
| − | Image:PussyWillowBoston.jpg|''[[Salix discolor]]'' used in a [[Floristry|decorative arrangement]] outside a [[hotel]] in [[Boston, Massachusetts]].
| |
| − | </gallery>
| |
| − |
| |
| − | == References==
| |
| − | * Albury/Wodonga Willow Management Working Group (AWWMWG). 1998. [http://www.dse.vic.gov.au/dpi/nreninf.nsf/childdocs/-1C62D26CD3AF6FE44A2568B300051289-8E21A59E53B35BEFCA256BC80005C14F-E1EB709D7DCE1BC9CA256F070003E8D8-FAC3FFA202EA6384CA256BCF000AD522?open Willows along watercourses: Managing, removing and replacing]. ''Department of Primary Industries, State Government of Victoria''. Retrieved October 20, 2008.
| |
| − |
| |
| − | * Breasted, J. 2007. [http://www.touregypt.net/edwinsmithsurgical.htm The Edwin Smith Papyrus]. ''Tour Egypt''. Retrieved October 20, 2008.
| |
| − |
| |
| − | * Cremer, K. W. 2003. [http://www.hoadley.net/cremer/willows/docs/WillowInBiodiversity.pdf Introduced willows can become invasive pests in Australia]. ''Biodiversity'' 4(4): 17-24. Retrieved October 20, 2008.
| |
| − |
| |
| − | * Hone, W. 1826. [http://www.uab.edu/english/hone/etexts/edb/day-pages/221-aug09.html August 9. Floral directory. The willow]. ''The Every-Day Book'' (Electronic Edition).
| |
| − |
| |
| − | * Keeler, H. L. 1900. ''Our Native Trees and How to Identify Them''. New York: Charles Scriber's Sons.
| |
| − |
| |
| − | * Mabberley, D. J. 1997. ''The Plant Book''. Cambridge: Cambridge University Press. ISBN 0521414210.
| |
| − |
| |
| − | * Newsholme, C. 2003. ''Willows: The Genus Salix''. Portland, OR: Timber Press. ISBN 0881925659.
| |
| − |
| |
| − | * Nobel Prize. 2008. [http://www.nobelprizes.com/nobel/medicine/aspirin.html An aspirin a day keeps the doctor at bay: The world's first blockbuster drug is a hundred years old this week]. ''Nobelprizes.com''. Retrieved October 20, 2008.
| |
| − |
| |
| − | * Warren-Wren, S. C. 1992. ''The Complete Book of Willows''. South Brunswick, A.S. Barnes. ISBN 049801262X
| |
| − |
| |
| − |
| |
| − | [[Category:Life sciences]]
| |
| − | [[Category:Plants]]
| |
| − |
| |
| − | {{credit|Willow|246583580}}
| |
