Ulmus 'Nanguen'

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Ulmus hybrid
Lutèce™, aged 8 years, Great Fontley, UK
Lutèce™, aged 8 years, Great Fontley, UK
Hybrid parentage
'Plantyn' × ('Bea Schwarz' × 'Bea Schwarz' selfed)
Cultivar
'Nanguen'

Lutèce™
Origin
Wageningen, The Netherlands

One of the last Dutch hybrid cultivars to be released, 'Nanguen' (Lutèce™) is a complex fourth generation tree with an ancestry comprising four Field Elms U. minor, three Wych Elms U. glabra including the curious Exeter Elm, var. 'Exoniensis', and a frost-resistant selection of the Himalayan Elm U. wallichiana. Originally known simply as clone no. 812, it proved immune to Dutch elm disease when inoculated with unnaturally high doses of the causal fungus Ophiostoma novo-ulmi. Unlike its immediate predecessor, 'Columella', it is rarely monocormic, and develops a more natural, rounded shape similar to the native Field Elm. However, '812' was not commercially promoted by the Dutch owing to (unfounded) fears that it may prove susceptible to Coral Spot fungus Nectria cinnabarina. Instead, '812' was acquired by the French Institut National de la Recherche Agronomique (INRA), which subjected the tree to 20 years of field trials in the Bois de Vincennes, Paris, before releasing it for sale in 2002 as 'Nanguen' (Lutèce™).[1][2]

The cultivar is now being widely planted in cities, notably Paris, and rural areas of France.[3] In trials in southern England, the tree has proven very hardy, tolerant of sea winds, summer droughts, and ground waterlogged during winter. However, some trees proved susceptible to wind-rock where planted on soils saturated and softened by summer rains, necessitating staking for four or five years. Fast growing on moist, well-drained soils, gaining an average of 80 cm per annum, it commences flowering in late March when aged six years. The coarsely-toothed leaves appear relatively late, in early May, and are up to 10 cm long, bright green, with a rough upper surface.[4] Not yet 30 years old, the ultimate size of this cultivar remains unknown but, given its ancestry, should reach at least 30 m in height. The trees planted in the Bois de Vincennes attained an average height of 12.5 m with a trunk diameter of 22 cm at 20 years of age.[5]

Lutèce foliage
Lutèce foliage
Emergent Lutèce flowers
Emergent Lutèce flowers

Over 4000 'Nanguen' Lutèce™ have been planted on the Isle of Wight by the Island 2000 Trust, and in lower concentrations on the mainland, mostly by members of Butterfly Conservation in the hope the tree will host the White-letter Hairstreak butterfly Satyrium w-album, a monophagic species that remains in serious decline as a consequence of Dutch elm disease.[4]

Contents

[edit] Arboreta etc. accessions

[edit] Europe
North America

[edit] Nurseries

Europe

[edit] Etymology

Lutèce is the French derivation of Lutetia, the ancient Roman name for the settlement that later became Paris.

[edit] References

  1. ^ SAPHO. Ulmus LUTECE 'Nanguen', [1], La Menitre, France.
  2. ^ Department of Forest Health, Forest Health in France 2002 [2], Paris, France.
  3. ^ Institut National de la Recherche Agronomique. Lutèce, a resistant variety brings elms back to Paris [3], Paris, France.
  4. ^ a b Brookes, A. H. (2006). An evaluation of disease-resistant hybrid and exotic elms as larval host plants for the White-letter Hairstreak Satyrium w-album, Part 1 [4]. Butterfly Conservation. Lulworth, UK.
  5. ^ Pinon, J. (2007). Les ormes résistants à la graphiose. Forêt-entreprise, No. 175 - Juillet 2007, p 37-41, IDF [5], Paris, France.

[edit] Pictures

Photographs of the Isle of Wight's Island 2000 Trust planting Lutece elms can be seen at the Flickr website here at [11] and [12].