Ulmus 'Coolshade'

Ulmus hybrid
'Coolshade', Tenantry Down Road, Brighton. Photo: Ronnie Nijboer, Bonte Hoek kwekerijen
Details
Hybrid parentage	U. rubra × U. pumila
Cultivar	'Coolshade'
Origin	Sarcoxie, Missouri, USA

The American hybrid cultivar Ulmus 'Coolshade' was cloned from a crossing of the Slippery, or Red, Elm Ulmus rubra and the Siberian Elm Ulmus pumila at the Sarcoxie Nurseries, Sarcoxie, Missouri, in 1946.

Description

Described as a being of rapid, stocky growth with a compact crown resistant to breakage under ice and snow, its foliage a very dark green.^[1][2]

Pests and diseases

Reputedly tolerant of Dutch elm disease, 'Coolshade' has not been tested by inoculation to determine the degree of resistance.

Cultivation

'Coolshade' was raised to create a disease-resistant tree that would not suffer the storm damage frequently sustained by the weak-wooded U. pumila. The tree was introduced to the UK in the 1960s (examples in Tenantry Down Road, Brighton).

Cultivars

• 'Improved Coolshade'

Accessions

North America

• Arnold Arboretum. Acc. no. 561-48

Europe

• Brighton & Hove City Council, UK, NCCPG Elm Collection [2] (two examples, at Ryecroft and Tenantry Down Road, Brighton).

References

1. ^ Green, P. S. (1964). Registration of cultivar names in Ulmus. Arnoldia, Vol. 24. Arnold Arboretum, Harvard University. [1]
2. ^ Bean, W. J. (1981). Trees and shrubs hardy in Great Britain, 7th edition. Murray, London.