Ulmus microcarpa

Ulmus microcarpa was named and first described by the Chinese botanist L. K. Fu, who discovered the tree in the Chayu broad-leaved forests of south-eastern Xizang at altitudes of around 2800  m during the 1973 Qinghai - Tibet Expedition. Unlike the majority of Tibet, the Chayu region has a subtropical highland climate featuring warm, wet, summers and mild, dry, winters (avg. annual rainfall 807 mm). Known as the Tibetan Elm, Ulmus microcarpa was introduced to the USA in 2006, and the UK in 2013; it remains one of the rarest species in cultivation.
Description
U. microcarpa can reach a height of 30 m in the wild, the trunk < 80  cm d.b.h.. The large oblong to elliptic leaves are 8.5–17 cm long by 5–8 cm broad with 5 mm petioles, likened by Fu to those of U. wallichiana and U. bergmanniana var. lasiophylla, but much smaller on juvenile plants. The leaves are borne on extraordinarily corky branchlets bestowing...