|A mature tree|
Populus alba, commonly called abele, silver poplar, silverleaf poplar, or white poplar, is a species of poplar, most closely related to the aspens (Populus sect. Populus). It is native from Morocco and the Iberian Peninsula through central Europe (north to Germany and Poland) to central Asia. It grows in moist sites, often by watersides, in regions with hot summers and cold to mild winters.
It is a medium-sized deciduous tree, growing to heights of up to 16–27 metres (52–89 ft) (rarely more), with a trunk up to 2 metres (6.6 ft) in diameter and a broad rounded crown. The bark is smooth and greenish-white to greyish-white with characteristic diamond-shaped dark marks on young trees, becoming blackish and fissured at the base of old trees. The young shoots are covered with whitish-grey down, including the small buds. The leaves are 4–15 cm (1 1⁄2–6 in) long, five-lobed, with a thick covering of white scurfy down on both sides but thicker underneath; this layer wears off the upper side but not the lower, which stays white until autumn leaf fall. Larger, deeply lobed leaves are produced on fast-growing young trees, and smaller, less deeply lobed leaves on older, slow-growing trees. The flowers are catkins up to 8 cm (3 1⁄4 in) long, produced in early spring; they are dioecious, with male and female catkins on separate trees; the male catkins are grey with conspicuous dark red stamens, the female catkins are greyish-green. The female catkins lengthen to 8–10 cm (3 1⁄4–4 in) after pollination, with several green seed capsules, maturing in late spring to early summer. It also propagates by means of root suckers growing from the lateral roots, often as far as 20–30 m (65–100 ft) from the trunk, to form extensive clonal colonies.
White poplar hybridises with the closely related Common Aspen Populus tremula; the resulting hybrid, known as grey poplar (Populus × canescens), is intermediate between its parents, with a thin grey downy coating on the leaves, which are also much less deeply lobed than White Poplar leaves. It is a very vigorous tree with marked hybrid vigour, reaching 40 m (130 ft) tall and a trunk diameter over 1.5 m (4 ft 11 in), much larger than either of its parents. Most Grey Poplars in cultivation are male, but female trees occur naturally and some of these are also propagated.
Cultivation and uses
White poplar requires abundant light and ample moisture, and stands up well to flood water and slightly acidic soils. Its green-and-white leaves makes it an effective ornamental tree but the root suckers may cause problems in some situations. It is very attractive as an open-grown tree in water meadows, and, because of its extensive root system and tolerance of salt, is also planted to strengthen coastal sand dunes.
The majority of White Poplars in cultivation in northern Europe are female trees.
White poplar was first introduced to North America in 1748 and has a long history in cultivation. It is now found in forty-three states throughout the contiguous U.S. It has come to be considered weedy or invasive; it has been banned in Connecticut and is the most common introduced tree species on Cape Breton Island.
The wood is soft but close-grained and easy to carve, shrinking very little during seasoning. It has been used for sculpture from Europe to China and the US. The Penitent Magdalene by Donatello is one 15th-century example.
According to ancient Roman mythology the White Poplar was consecrated to Hercules because he destroyed Cacus in a cavern adjoining the Aventine Hill, which was covered with these trees; and in the moment of his triumph he bound his brows with a branch of White Poplar as a token of his victory. Persons offering sacrifices to Hercules were always crowned with branches of this tree; and all who had gloriously conquered their enemies in battle wore garlands of it, in imitation of Hercules. Homer in the "Iliad" compares the fall of Simoisius when killed by Ajax to that of a poplar.
So falls a poplar that on watery ground
Raised high its head with stately branches crowned.
The white poplar is an invasive species in many parts of Australia. In Western Australia it has formed dense stands in disturbed wetlands from Perth to Albany and it is considered a threat to riparian vegetation in Victoria. It has spread along the Murrumbidgee River and in wet areas in rural parts of the ACT. Despite that, it is still sold in nurseries around Australia. White poplar is also an environmental weed in South Africa.
- Leuce (Leuka), was an Oceanid, and the lover of Hades (Pluto) until her death, after which Hades turned her into the white poplar tree, which became sacred for him from that moment on, and grew in the Elysian Fields. In Ancient Greco-Roman mythology, it is a symbol of a peaceful afterlife and a memory of those we love who have died. In the language of flowers its meaning is "time".
|Wikimedia Commons has media related to Populus alba.|
- Leaf and bark photos
- Tree identification
- Images, diseases, galls and fungi on treetrees.com
- EUFORGEN species page on Populus alba. Information, genetic conservation units and related resources.
- The Plant List: A Working List of All Plant Species, retrieved 11 May 2016
- "Populus alba". Germplasm Resources Information Network (GRIN). Agricultural Research Service (ARS), United States Department of Agriculture (USDA).
- Webb, C. J.; Sykes, W. R.; Garnock-Jones, P. J. 1988: Flora of New Zealand. Vol. IV. Naturalised Pteridophytes, Gymnosperms, Dicotyledons. 4. Christchurch, New Zealand, Botany Division, D.S.I.R.
- Flora Europaea: Populus alba
- Rushforth, K. (1999). Trees of Britain and Europe. Collins ISBN 0-00-220013-9.
- Flora of NW Europe: Populus alba
- Vedel, H., & Lange, J. (1960). Trees and Bushes in Wood and Hedgerow. Metheun & Co. Ltd., London.
- "PCA Alien Plant Working Group – White Poplar (Populus alba)". Nps.gov. 2009-07-07. Retrieved 2011-07-16.
- Keeler, H. L. (1900). Our Native Trees and How to Identify Them pp. 428–432. Charles Scriber's Sons, New York
- "PLANTS Profile for Populus alba (white poplar) | USDA PLANTS". Plants.usda.gov. 1999-10-19. Retrieved 2011-07-16.
- "white poplar, Populus alba (Salicales: Salicaceae)". Invasive.org. 2010-05-04. Retrieved 2011-07-16.
- US invasive state location map
- Ršsch, Petra, Chinese Wood Sculptures of the 11th to 13th centuries: Images of Water-moon Guanyin in Northern Chinese Temples and Western Collections, pp. 179-180, 2007, Columbia University Press, ISBN 3-8382-5662-X, 9783838256627; 
- "White Poplar". Weedy Connection. Retrieved 2015-10-18.
- "Poplar Tree Listing". Small Tree Farm. Retrieved 2015-10-18.