| Ulmus davidiana var. japonica 'Jacan' | |
|---|---|
 'Jacan', Sir Harold Hillier Gardens, UK | |
| Variety | Ulmus davidiana var. japonica |
| Cultivar | 'Jacan' |
| Origin | Canada |
The Japanese Elm cultivar Ulmus davidianavar.japonica 'Jacan' is a cold-resistant selection from Canada. The tree was raised by the Morden Research Station, Morden, Manitoba in the 1980s.
'Jacan' develops a rounded crown form typical of the species; the foliage turns a deep red in autumn. [1] The species does not sucker from roots. [2]
The tree is moderately resistant to Dutch elm disease, and elm leaf beetle Xanthogaleruca luteola . [3] The tree's foliage was adjudged "resistant" to Black Spot by the Plant Diagnostic Clinic of the University of Missouri .
'Jacan' has not been widely planted in Canada owing to restrictions imposed by the Canadian government on the movement of elms across the country, which severely limited its potential market. The tree was introduced to the UK (see Accessions) and Italy from Canada in the early 1980s, but was never in commerce in either country and thus remains very rare; it is not known to have been introduced to Australasia.
'Jacan' was crossed with 'Sapporo Autumn Gold' by the Istituto per la Protezione delle Piante, Florence; the selection identified as 'FL441'. Although it performed well in trials, being noted for its abundant foliage, 'FL441' was never patented or released to commerce. [4]
None known.
None known.
Ulmus davidiana var. japonica, the Japanese elm, is one of the larger and more graceful Asiatic elms, endemic to much of continental northeast Asia and Japan, where it grows in swamp forest on young alluvial soils, although much of this habitat has now been lost to intensive rice cultivation.
Ulmus laciniata(Trautv.) Mayr, known variously as the Manchurian, cut-leaf, or lobed elm, is a deciduous tree native to the humid ravine forests of Japan, Korea, northern China, eastern Siberia and Sakhalin, growing alongside Cerciphyllum japonicum, Aesculus turbinata, and Pterocarya rhoifolia, at elevations of 700–2200 m, though sometimes lower in more northern latitudes, notably in Hokkaido.
Ulmus chenmouiW. C. Cheng, commonly known as the Chenmou, or Langya Mountain elm, is a small deciduous tree from the more temperate provinces of Anhui and Jiangsu in eastern China, where it is found at elevations below 200 m on the Langya Shan and Baohua Shan mountains. The tree was unknown in the West until 1979, when seeds were sent from Beijing to the De Dorschkamp research institute at Wageningen in the Netherlands.
Ulmus 'Homestead' is an American hybrid elm cultivar raised by Alden Townsend of the United States National Arboretum at the Nursery Crops Laboratory in Delaware, Ohio. The cultivar arose from a 1970 crossing of the Siberian Elm Ulmus pumila with the hybrid N 215, the latter grown from seed sent in 1960 to the University of Wisconsin-Madison elm breeding team by Hans Heybroek of the De Dorschkamp Research Institute in the Netherlands. Tested in the US National Elm Trial coordinated by Colorado State University, 'Homestead' averaged a survival rate of 85% after 10 years. 'Homestead' was released to commerce without patent restrictions in 1984.
The hybrid elm cultivar Ulmus × hollandica 'Pioneer' is an American clone arising from the crossing of two European species, Wych Elm U. glabra and Field Elm U. minor. Raised by the USDA station at Delaware, Ohio, in 1971, 'Pioneer' was released to commerce in 1983.
Ulmus 'Sapporo Autumn Gold' is one of the most commercially successful hybrid elm cultivars ever marketed, widely planted across North America and western Europe, although it has now been largely supplanted by more recent introductions. Arising from a chance crossing of the Japanese elm and Siberian elm, seed was sent in 1958 by Prof. Nobuku Takahashi and his colleagues at the Sapporo Botanical Garden of Hokkaido University, Sapporo, to Eugene Smalley at the University of Wisconsin–Madison. The patent issued in 1975 has expired, and there are now no propagation restrictions.
Ulmus 'Morton' is an elm cultivar cloned from a putative intraspecific hybrid planted at the Morton Arboretum in 1924, which itself originated as seed collected from a tree at the Arnold Arboretum in Massachusetts. Although this tree was originally identified as Ulmus crassifolia, it is now believed to have been a hybrid of the Japanese elm and Wilson's elm. Accolade has proven to be the most successful cultivar tested in the US National Elm Trial, averaging a survival rate of 92.5% overall.
Ulmus 'Columella' is a Dutch elm cultivar raised by the Dorschkamp Research Institute for Forestry & Landscape Planning, Wageningen, from a selfed or openly pollinated seedling of the hybrid clone 'Plantyn' sown in 1967. It was released for sale in 1989 after proving extremely resistant to Dutch elm disease following inoculation with unnaturally high doses of the pathogen, Ophiostoma novo-ulmi. However, propagated by grafting onto Wych Elm rootstocks, graft failure owing to incompatibility has become a common occurrence in the Netherlands.
Ulmus 'Cathedral' is a hybrid cultivar raised at University of Wisconsin–Madison patented in 1994. Arising from a chance crossing of the Japanese elm and Siberian elm, seed was sent in 1958 by Prof. Nobuku Takahashi and his colleagues at the Sapporo Botanical Garden of Hokkaido University, Sapporo, to Eugene Smalley at Wisconsin–Madison; 'Cathedral' is thus a sibling of 'Sapporo Autumn Gold'.
The American Elm cultivar Ulmus americana 'Valley Forge' was raised by the Agricultural Research Service in Maryland. The tree was released to wholesale nurseries without patent restrictions by the U. S. National Arboretum in 1995 after proving to have a high resistance to Dutch elm disease. 'Valley Forge' proved only moderately successful in the US National Elm Trial, averaging a survival rate of 66.7% overall, owing largely to environmental factors rather than susceptibility to disease.
The Japanese Elm cultivar Ulmus davidianavar.japonica 'Discovery' is a cold-resistant selection from Canada, raised along with 'Freedom' in the 1980s by Dr Wilbert Ronald, of Jeffries Nurseries Ltd. and Rick Durrand of Shade Consulting Services, Portage la Prairie, Manitoba.
The American elm cultivar Ulmus americana 'Brandon' was raised by Lacombe Nurseries Lacombe, Alberta, Canada, before 1969; it may be synonymous with another cultivar from the same source known as 'Patmore', selected and raised by R. H. Patmore from a native tree in Brandon, Manitoba.
The Japanese Elm cultivar Ulmus davidianavar.japonica 'Freedom' is another cold-resistant selection from Canada, raised along with 'Discovery' in the 1980s by Dr Wilbert Ronald, of Jeffries Nurseries Ltd., and Rick Durrand of Shade Consulting Services, Portage la Prairie, Manitoba.
Ulmus davidianavar.japonica 'Thomson' is a hardy, cold-resistant cultivar of the Japanese Elm assessed by the Prairie Farm Rehabilitation Administration (PFRA) Nursery at Indian Head, Saskatchewan, in the 1970s as part of its shelterbelt tree research..
The Japanese Elm cultivar Ulmus davidianavar.japonica 'Mitsui Centennial' is a cold-resistant selection raised at the Morden Experimental Station, Manitoba, Canada, in the 1970s.
The American elm cultivar Ulmus americana 'Lewis & Clark' is a development from the North Dakota State University (NDSU) Research Foundation breeding programme, released in 2004 to commemorate the 200th anniversary of the eponymous expedition. The cultivar was cloned from a tree discovered in 1994 along the Wild Rice River south west of Fargo, North Dakota, where all those around it had succumbed to Dutch elm disease; the tree remains in perfect health (2008). Prairie Expedition proved only moderately successful in the US National Elm Trial, averaging a survival rate of 62.6% overall, potentially due to environmental factors rather than susceptibility to Dutch elm disease.
Ulmus davidianavar.japonica 'JFS-Bieberich' is a Japanese Elm cultivar that was raised by the Sunshine Nursery, Oklahoma, from seed collected in China by proprietor Steve Bieberich. Emerald Sunshine proved only moderately successful in the US National Elm Trial, averaging a survival rate of 70% overall.
The Japanese elm cultivar Ulmus davidianavar.japonica 'Prospector' was originally treated as a cultivar of Wilson's elm U. wilsonianaSchneid., a species sunk as Ulmus davidiana var. japonica by Fu. A U.S. National Arboretum introduction, it was selected in 1975 from a batch of 1965 seedlings in Delaware, Ohio, and released without patent restrictions in 1990. 'Prospector' proved moderately successful in the US National Elm Trial, averaging a survival rate of 76% overall.
Ulmus laciniata var. nikkoensisRehder, the Nikko elm, was discovered as a seedling near Lake Chūzenji, near Nikkō, Japan, and obtained by the Arnold Arboretum in 1905. The taxonomy of the tree remains a matter of contention, and has been considered possibly a hybrid of U. laciniata and U. davidiana var. japonica. However, in crossability experiments at the Arnold Arboretum in the 1970s, U. laciniata, a protogynous species, was found to be incompatible with U. davidiana var. japonica, which is protandrous.
Ulmus parvifolia, commonly known as the Chinese elm or lacebark elm, is a species native to eastern Asia, including China, India, Japan, Korea, and Vietnam. It has been described as "one of the most splendid elms, having the poise of a graceful Nothofagus".