1 soft light-colored nondurable wood of the poplar
2 any of numerous trees of north temperate regions having light soft wood and flowers borne in catkins [syn: poplar tree]
any of various deciduous trees of the genus Populus
- Albanian: plep
- Bosnian: topola
- Bulgarian: топола
- Catalan: pollancre
- Croatian: topola
- Czech: topol
- Dutch: populier
- Esperanto: poplo
- Estonian: pappel
- French: peuplier
- German: Pappel
- Hungarian: nyár
- Italian: pioppo
- Latin: populus
- Polish: topola
- Romanian: plop
- Russian: тополь (tópol')
- Spanish: álamo
Populus is a genus of between 25–35 species of flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar, aspen, and cottonwood.
They are medium-sized to large or very large deciduous trees growing to 15–50 m tall, with trunks up to 2.5 m diameter. The bark on young trees is smooth, white to greenish or dark grey, often with conspicuous lenticels; on old trees it remains smooth in some species, but becomes rough and deeply fissured in others. The shoots are stout, with (unlike in the related willows) the terminal bud present. The leaves are spirally arranged, and vary in shape from triangular to circular or (rarely) lobed, and with a long petiole; in species in the sections Populus and Aegiros, the petioles are laterally flattened, so that breezes easily cause the leaves to wobble back and forth, giving the whole tree a "twinkling" appearance in a breeze. Leaf size is very variable even on a single tree, typically with small leaves on side shoots, and very large leaves on strong-growing lead shoots. The leaves often turn bright gold to yellow before they fall during autumn.
The flowers are mostly dioecious (rarely monoecious) and appear in early spring before the leaves. They are borne in long, drooping, sessile or pedunculate catkins produced from buds formed in the axils of the leaves of the previous year. The flowers are each seated in a cup-shaped disk which is borne on the base of a scale which is itself attached to the rachis of the catkin. The scales are obovate, lobed and fringed, membranous, hairy or smooth, usually caducous. The male flowers are without calyx or corolla, and comprise a group of 4–60 stamens inserted on a disk; filaments short, pale yellow; anthers oblong, purple or red, introrse, two-celled; cells opening longitudinally. The female flower also has no calyx or corolla, and comprises a single-celled ovary seated in a cup-shaped disk. The style is short, with 2–4 stigmas, variously lobed, and numerous ovules. Pollination is by wind, with the female catkins lengthening considerably between pollination and maturity. The fruit is a two to four-valved capsule, green to reddish-brown, mature in mid summer, containing numerous minute light brown seeds surrounded by tufts of long, soft, white hairs which aid wind dispersal.
Poplars of the cottonwood section are often wetlands or riparian trees. The aspens are among the most important boreal broadleaf trees. this classification is followed below. Recent genetic studies have largely supported this, though showing that the relationships are somewhat more complex, with some reticulate evolution due to past hybridisation and introgression events between the groups; some species (noted below) had differing relationships indicated by their nuclear DNA (paternally inherited) and chloroplast DNA sequences (maternally inherited), a clear indication of likely hybrid origin. Hybridisation continues to be common in the genus, with several hybrids between species in different sections known. - black poplars or cottonwoods. North America, Europe, western Asia; temperate
- Populus section Tacamahaca - balsam
poplars. North America, Asia; cool temperate
- Populus angustifolia - Willow-leaved Poplar or Narrowleaf Cottonwood. Central North America.
- Populus balsamifera - Ontario Balsam Poplar. Northern North America.
- Populus laurifolia - Laurel-leaf Poplar. Central Asia.
- Populus maximowiczii - Maximowicz' Poplar. Northeast Asia.
- Populus simonii - Simon's Poplar. Northeast Asia.
- Populus szechuanica Northeast Asia. Placed here by nuclear DNA; cpDNA places in sect. Aegiros.
- Populus trichocarpa - Western Balsam Poplar or Black Cottonwood. Western North America.
- Populus tristis - Northeast Asia. Placed here by nuclear DNA; cpDNA places in sect. Aegiros.
In the September 2006 issue of Science, it was announced that Populus trichocarpa'' was the first tree to have its full DNA code sequenced.
Cultivation and usesMany poplars are grown as ornamental trees, with numerous cultivars selected. They have the advantage of growing very big very fast. Trees with fastigiate (erect, columnar) branching are particularly popular, and very widely grown across Europe and southwest Asia in particular. However, like willows, poplars have very vigorous and invasive root systems stretching up to 40 m from the trees; planting close to houses or ceramic water pipes may result in damaged foundations and cracked walls and pipes due to their search for moisture.
Fast-growing hybrid poplars are grown on plantations in many areas for pulpwood and used for the manufacture of paper. The wood is generally white, often with a slightly yellowish cast. It is also sold as inexpensive hardwood timber, used for pallets and cheap plywood; more specialised uses include matches and the boxes in which camembert cheese is sold. Poplar wood is widely used in the snowboard industry for the snowboard "core", because it has exceptional flexibility.
Poplar was the most common wood used in Italy for panel paintings; the Mona Lisa and indeed most famous early renaissance Italian paintings are on poplar.
Due to its tannic acid content, the bark has been used in Europe for tanning leather.
poplar in Arabic: حور
poplar in Azerbaijani: Qovaq
poplar in Bulgarian: Топола
poplar in Catalan: Pollancre
poplar in Czech: Topol
poplar in Corsican: Piobu (genaru)
poplar in Danish: Poppel
poplar in German: Pappeln
poplar in Spanish: Populus
poplar in Esperanto: Poploj
poplar in Persian: سپیدار
poplar in French: Peuplier
poplar in Korean: 사시나무속
poplar in Italian: Populus
poplar in Hebrew: צפצפה (עץ)
poplar in Georgian: ვერხვი
poplar in Latin: Populus (genus plantarum)
poplar in Latvian: Apses
poplar in Lithuanian: Tuopa
poplar in Hungarian: Nyárfa
poplar in Dutch: Populier
poplar in Japanese: ポプラ
poplar in Norwegian: Popler
poplar in Polish: Topola
poplar in Portuguese: Choupo
poplar in Romanian: Plop (arbore)
poplar in Quechua: Alamu
poplar in Russian: Тополь
poplar in Sicilian: Populus
poplar in Slovenian: Topoli
poplar in Serbian: Топола (дрво)
poplar in Finnish: Populus
poplar in Swedish: Poppelsläktet
poplar in Vietnamese: Dương (thực vật)
poplar in Turkish: Kavak (bitki)
poplar in Ukrainian: Тополя
poplar in Chinese: 杨属