The Morton Arboretum has held a significant Ulmus collection dating almost back to the institution’s founding. Though initially comprised of a diverse assemblage of European cultivars, the collection really expanded in scope during the 1990’s owing to breeding and research efforts. The Morton Arboretum had initiated a selection and breeding program to develop elm cultivars resembling the American Elm (Ulmus americana), but resistant to the devastating Dutch Elm Disease. Species accessioned during this time included rare to cultivation East Asian taxa such as Ulmus castanaeifolia, Ulmus glaucescens var. lasiocarpa, and Ulmus microcarpa. At the culmination of these efforts, the Arboretum released five elm cultivars, most notably Accolade™ elm (Ulmus davidiana var. japonica ‘Morton’). The Morton Arboretum's Ulmus collection was accredited by Plant Collections Network in 2001. Future efforts for development of the Ulmus collection include plant exploration in China for acquisition of additional east Asian taxa, as well as trialing and evaluation of Ulmus cultivars recommended or intended for planting in the Upper Midwest region.