Siberian elm in the Neponset River floodplain. This tree has been introduced from Asia. It is not infrequent at roadsides, waste places, and woodland borders. In floodplains it becomes pyramidal and rather tall (to 25 m); otherwise, can be a shrub or smaller tree (about 10 m). Its mature bark is rough, branches and younger trunks are rather smooth, grayish.