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''Salix caprea'' (goat willow, also known as the pussy willow or great sallow) is a common species of willow native to Europe and western and central Asia.〔Meikle, R. D. (1984). ''Willows and Poplars of Great Britain and Ireland''. BSBI Handbook 4. ISBN 0-901158-07-0.〕 It is a deciduous shrub or small tree, reaching a height of , rarely to 13 m. The leaves are 3–12 cm long and from 2–8 cm wide, broader than most other willows. The flowers are soft silky, and silvery 3-7-cm-long catkins are produced in early spring before the new leaves appear; the male and female catkins are on different plants (dioecious). The male catkins mature yellow at pollen release, the female catkins mature pale green. The fruit is a small capsule 5–10 mm long containing numerous minute seeds embedded in fine, cottony hairs. The seeds are very small (about 0.2 mm) with the fine hairs aiding dispersal; they require bare soil to germinate.〔〔Rushforth, K. (1999). ''Trees of Britain and Europe''. Collins. ISBN 0-00-220013-9.〕 The two varieties are:〔 *''S. c.'' var. ''caprea'' - lowland regions throughout the range, leaves thinly hairy above, densely hairy below, 5–12 cm long, stipules persistent until autumn *''S. c.'' var. ''sphacelata'' (Sm.) Wahlenb. (syn. ''S. caprea'' var. ''coaetanea'' Hartm.; ''S. coaetanea'' (Hartm.) Floderus) - high altitudes in the mountains of central and northern Europe (Alps, Carpathians, Scotland, Scandinavia), leaves densely silky-hairy on both sides, 3–7 cm long, stipules early deciduous The scientific name, and the common name goat willow, probably derive from the first known illustration of the species in Hieronymus Bock's 1546 ''Herbal'', where the plant is shown being browsed by a goat. The species was historically also widely used as a browse for goats, to which Bock's illustration may refer.〔Bean, W. J. (1980). ''Trees and Shrubs Hardy in the British Isles''. ISBN 0-7195-2428-8.〕 ==Ecology== ''S. caprea'' occurs both in wet environments, such as riverbanks and lake shores, and in drier sites, wherever bare soil becomes available due to ground disturbance.〔 Hybrids with several other willow species are common, notably with ''Salix cinerea'' (''S. × reichardtii''), ''Salix aurita'' (''S. × multinervis''), ''Salix viminalis'' (''S. × smithiana''), and ''Salix purpurea'' (''S. × sordida''). Populations of ''S. caprea'' often show hybrid introgression.〔〔 Unlike almost all other willows, pure specimens do not take root readily from cuttings; if a willow resembling the species does root easily, it is probably a hybrid with another species of willow.〔 The leaves are used as a food resource by several species of Lepidoptera, and are also commonly eaten by browsing mammals. Willows are very susceptible to gall inducers, and the midge ''Rhabdophaga rosaria'' forms the camellia gall on ''S. caprea''.〔(Gall Inducers )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Salix caprea」の詳細全文を読む スポンサード リンク
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