'New Horizon'

HYBRID CULTIVAR

Ulmus davidiana var. japonica × U. pumila

ORIGIN

Wisconsin Alumni Research Foundation (WARF); released 1995

DESCRIPTION

The tree initially has a compact, pyramidal form, with comparatively dense foliage comprising glabrous, dark-green, elliptical leaves < 12 cm long by 7 cm broad, occasionally without the asymmetric bases typical of the genus. Flowering, and consequent fruiting, is meagre, a trait in-herited from its Japanese elm parent. The tree increases in height only slowly, while its trunk thickens comparatively quickly. A trait inherited from its Siberian Elm parent, the crown of ‘New Horizon’ can occasionally suffer natural twig dieback over winter, disfiguring the tree. Moreover, ‘NH’ is the most sensitive of all the trees on test to ground conditions, but nevertheless has proven able to survive several months’ winter inundation. Available only as standards from Hilliers, with prices starting at £360, it was found colonized by the White-letter Hairstreak in London in 2017.

PERFORMANCE

Stability

Resistance to exposure

Resemblance to native elm

Suitability for street planting

Rate of growth

Tolerance of waterlogging

Tolerance of drought