Ulmus pumila aka Siberian Elm

Ulmus pumila, also known as the Siberian elm, Asiatic elm, or dwarf elm, is a deciduous tree that is native to Central Asia, eastern Siberia, the Russian Far East, Mongolia, Tibet, northern China, India (northern Kashmir) and Korea. It is a relatively fast-growing tree that can reach heights of up to 15m, with a d.b.h. of up to 1m. The bark is dark gray and irregularly longitudinally fissured, while the branchlets are yellowish-gray and either glabrous or pubescent. The leaves are elliptic-ovate to elliptic-lanceolate and can measure between 2-8 × 1.2-3.5 cm, with the color changing from dark green to yellow in autumn. In early spring, before the leaves emerge, the perfect, apetalous wind-pollinated flowers bloom for one week in tight fascicles on last year's branchlets. However, flowers emerging in early February are often damaged by frost, leading to this species being dropped from the Dutch elm breeding program. The wind-dispersed samarae are whitish-tan and orbicular to rarely broadly obovate or elliptical, measuring between 1-2 × 1-1.5 cm, and glabrous except for pubescence on the stigmatic surface. The tree is able to self-pollinate successfully and can sucker readily from its roots. While the Siberian elm has been widely cultivated throughout Asia, North America, Argentina, and southern Europe, becoming naturalized in many places, notably across much of the United States, it is relatively rare as a houseplant. When grown indoors, it requires long-lasting, direct light and should be less than 1 foot from a window. It prefers soil that is good at retaining moisture and doesn't typically require added fertilizers if repotted each time it doubles in size. In its native environment, the tree may live to be between 100 and 150 years old, with a giant specimen located in the south Gobi, measuring 5.55 m in girth in 2009 and estimated to exceed 250 years.