Ulmus 'Nana'

The elm cultivar Ulmus 'Nana' is a very slow growing shrub that with time forms a small tree. It was believed for many years to be a form of Ulmus glabra and is known widely as the 'Dwarf Wych Elm'. However, the ancestry of 'Nana' has been disputed in more recent years, Melville considering the specimen once grown at Kew to have been a cultivar of Ulmus × hollandica.

Description

The tree rarely exceeds 5 m in height, but is often broader. The dark green leaves are smaller than the type, < 11 cm long by 8 cm broad. Green describes it as a very distinct variety not growing above 60 cm in 10 to 12 years. A specimen at Kew was described by Henry as 'a slow-growing hemispherical bush that has not increased appreciably in size for many years'.

Pests and diseases

The low height of the tree should ensure that it avoids colonisation by Scolytus bark beetles and thus remain free of Dutch elm disease.

Cultivation

The tree is still occasionally found in arboreta and gardens in the UK, and has been introduced to North America and continental Europe; it is not known in Australasia.