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The elm cultivar 'Purpurea' K.Koch 〔Koch, K. ''Dendr.'' 2 (1), 416 (1872)〕 is probably synonymous with the tree listed by Henry (1913) as ''Ulmus montana (: glabra)'' var. ''atropurpurea'',〔Elwes, H. J. & Henry, A. (1913). ''The Trees of Great Britain & Ireland''. Vol. VII. pp 1868. Private publication, Edinburgh. ()〕 raised at the Späth nursery in Germany c.1881 but later classed as a cultivar by Boom () in ''Ned. Dendr.'' 1: 157, 1959.〔Green, P. S. (1964). Registration of cultivar names in Ulmus. ''Arnoldia'', Vol. 24. Arnold Arboretum, Harvard University. ()〕 Henry also listed an ''Ulmus campestris (:procera)'' var. ''purpurea'' Petz. & Kirchn.,〔Elwes, H. J. & Henry, A. (1913). ''The Trees of Great Britain & Ireland''. Vol. VII. pp 1905. Private publication, Edinburgh.〕〔Petzold & Kirchner, ''Arb. Musc.'' 558 (1864)〕 with a description matching that of 'Purpurea', and adding that though it was grown at Kew as ''U. montana (:glabra)'' var. ''purpurea'' it was "probably of hybrid origin". The ancestry of the tree remains obscure, but the fact that 'Purpurea' occasionally produces suckers suggests an ''Ulmus minor'' hybrid origin. F. J. Fontaine conjectured ''U. glabra'' × ''U. minor'' 'Stricta',〔Bean, W. J. (1988) ''Trees and shrubs hardy in Great Britain'', 8th edition, Murray, London.〕 placing it in the ''Ulmus × hollandica'' group. Both the leaves and the habit of 'Purpurea' appear to support this conjecture. However, ''U. glabra'' occasionally produces red- or purple-flushed new leaves; an elm in the gardens of the Hedvig Eleonora Church, Östermalm, Stockholm, is listed as ''Ulmus procera'' 'Purpurea', but in form, fruit and foliage it appears to be a wych elm with a purplish tinge to its leaves.〔(www.tradgardsakademin.se )〕 In Europe there is also a putative small-leaved elm ''Ulmus minor'' 'Purpurascens'. In Australia cultivars by the name of ''U. glabra'' 'Purpurea', ''U. procera'' 'Purpurea' and ''U. purpurea'' appear in old nursery catalogues dating from 1886, but these are now believed to be synonymous with the cultivar currently known there as ''U.'' × ''hollandica'' 'Purpurascens', the name given by F. J. Fontaine to 'Purpurea'.〔F. J. Fontaine, ''Dendroflora'' No.5, (1968)〕〔Bean, W. J. (1988) ''Trees and shrubs hardy in Great Britain'', 8th edition, Murray, London, p.640〕 An elm obtained in 1922 from H. Kohankie & Son was listed by the Morton Arboretum, Illinois, as ''Ulmus procera'' 'Purpurea',〔''Ulmus procera'' 'Purpurea': Morton Arboretum Catalogue, Accession no. 593-22〕 but without description. In North America, purple-leaved elms encountered in the fall are likely to be the new hybrid ''Ulmus'' 'Frontier'. ==Description== 'Purpurea' grows to > 25 m in height, and is short-trunked with straggling, irregular, open ascending branches; the bark has a reddish-brown hue. The tree has slightly folded, dark-green leaves (the darkest green of all the elms) which, like the shoots, have a brief dark-purple flush in spring.〔Photograph of newly emerged leaves of 'Purpurea' in Denmark, www.loenbaek.dk ()〕〔Emerging 'Purpurea' leaves photographed against sunlight, www.kuningas.ee ()〕〔(Photograph of 'Purpurea' cuttings, www.kuningas.ee )〕 Prior to flushing, the leaf-buds are long, sharply pointed, and dark purple. The flowers, too, emerge a uniform dark purple. The fruit, tinged purple, is small and intermediate between ''glabra'' and ''minor''. After the spring purple flush, the leaves become olive green then darken in the summer. Their underside remains paler. The leaves' increasing fold as the year progresses gives the foliage a greyish hue later.〔 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「Ulmus 'Purpurea'」の詳細全文を読む スポンサード リンク
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