White Willow

Revision as of 17:04, 18 August 2010 by Raffi (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)


White Willow foliage; note white undersides of leaves


Plant Characteristics
Habit   tree

Height: 80 ft"ft" can not be assigned to a declared number type with value 80.
Width: 30 ft"ft" can not be assigned to a declared number type with value 30.
Lifespan: perennial
Bloom: early spring, mid spring, late spring
Cultivation
Exposure: sun
Water: wet, moist
Features: flowers
USDA Zones: 2 to 10
Sunset Zones: 1-24, 30-45
Scientific Names

Salicaceae >

Salix >

alba >


Salix alba (White Willow) is a species of willow native to Europe and western and central Asia.[1][2] The name derives from the white tone to the undersides of the leaves.

It is a medium-sized to large deciduous tree growing up to 10–30 m tall, with a trunk up to 1 m diameter and an irregular, often leaning crown. The bark is grey-brown, deeply fissured in older trees. The shoots in the typical species are grey-brown to green-brown. The leaves are paler than most other willows, due to a covering of very fine silky white hairs, particularly on the underside; they are 5–10 cm long and 0.5–1.5 cm wide. The flowers are produced in catkins in early spring, and pollinated by insects. It is dioecious, with male and female catkins on separate trees; the male catkins are 4–5 cm long, the female catkins 3–4 cm long at pollination, lengthening as the fruit matures. When mature in mid summer, the female catkins comprise numerous small (4 mm) capsules each containing numerous minute seeds embedded in white down which aids wind dispersal.[1][2][3]


Read about White Willow in the Standard Cyclopedia of Horticulture 

Salix alba, Linn. White Willow. Large tree, with short and thick trunk, not excurrent in habit: branches yellowish brown: lvs. ashy gray and silky throughout, giving a white appearance to the whole tree, 2-4 in. long, elliptical. —Heretofore associated with the next species, from which it differs in color of twigs and vesture and color of lvs., as also in its general habit. It is only occasionally seen in Amer. Var. splendens, Anderss. (S. alba var. argentea, Wimm. S. regalis, Hort.). Lvs. densely silky on both sides, nearly silvery-white while young. The forms of this species not easily distinguishable from one another, can be readily distinguished from many other species. Var. calva, G. F. W. Mey. (S. alba var. caerulea, Smith). Of pyramidal habit: lvs. larger, at maturity glabrescent, more bluish green above and more glaucous below.


The above text is from the Standard Cyclopedia of Horticulture. It may be out of date, but still contains valuable and interesting information which can be incorporated into the remainder of the article. Click on "Collapse" in the header to hide this text.


Cultivation

Do you have cultivation info on this plant? Edit this section!

Propagation

Do you have propagation info on this plant? Edit this section!

Pests and diseases

White Willows are fast-growing, but relatively short-lived, being susceptible to several diseases, including watermark disease caused by the bacterium Brenneria salicis (named because of the characteristic 'watermark' staining in the wood; syn. Erwinia salicis) and willow anthracnose, caused by the fungus Marssonina salicicola. These diseases can be a serious problem on trees grown for timber or ornament.

Varieties

A number of cultivars and hybrids have been selected for forestry and horticultural use:[1][2]

  • Salix alba 'Caerulea' (Cricket-bat Willow; syn. Salix alba var. caerulea (Sm.) Sm.; Salix caerulea Sm.) is grown as a specialist timber crop in Britain, mainly for the production of cricket bats, and for other uses where a tough, lightweight wood that does not splinter easily, is required. It is distinguished mainly by its growth form, very fast growing with a single straight stem, and also by its slightly larger leaves (10–11 cm long, 1.5–2 cm wide) with a more blue-green colour. Its origin is unknown; it may be a hybrid between White Willow and Crack Willow, but this is not confirmed.[1]
  • Salix alba 'Vitellina' (Golden Willow; syn. Salix alba var. vitellina (L.) Stokes) is a cultivar grown in gardens for its shoots, which are golden yellow for 1–2 years before turning brown. It is particularly decorative in winter; the best effect is achieved by coppicing it every 2–3 years to stimulate the production of longer young shoots with better colour. Other similar cultivars include 'Britzensis', 'Cardinal', and 'Chermesina', selected for even brighter orange-red shoots.
  • Salix alba 'Sericea' (Silver Willow) is a cultivar where the white hairs on the leaves are particularly dense, giving it more strongly silvery-white foliage.
  • Salix alba 'Vitellina-Tristis' (Golden Weeping Willow, synonym 'Tristis') is a weeping cultivar with yellow branches that become reddish-orange in winter. It is now rare in cultivation and has been largely replaced by Salix Sepulcralis Group 'Chrysocoma'. It is however still the best choise in very cold parts of the world like Canada, the Northern U.S.A. and Russia.

It readily forms natural hybrids with Crack Willow Salix fragilis, the hybrid being named Salix × rubens Schrank.[1]

Gallery

References

External links


  1. 1.0 1.1 1.2 1.3 1.4 Meikle, R. D. (1984). Willows and Poplars of Great Britain and Ireland. BSBI Handbook No. 4. ISBN 0-901158-07-0.
  2. 2.0 2.1 2.2 Rushforth, K. (1999). Trees of Britain and Europe. Collins ISBN 0-00-220013-9.
  3. Mitchell, A. F. (1974). A Field Guide to the Trees of Britain and Northern Europe. Collins ISBN 0-00-212035-6