Betula nigra Betula nigra Betula nigra, the black birch, river birch or water birch, is a species of birch native to the Eastern United States from New Hampshire west to southern Minnesota, and south to northern Florida and west to Texas. It is one of the few heat-tolerant birches in a family of mostly cold-weather trees which do not thrive in USDA Zone 6 and up. "B. nigra" commonly occurs in floodplains and swamps. "Betula nigra" is a deciduous tree growing to with a trunk in diameter. The base of the tree is often divided into multiple slender trunks. Bark Bark characteristics
Cyclocarya female catkins 25–30 cm long at maturity, bearing several small winged nuts with a circular wing 2.5–6 cm diameter right round the nut (instead of two wings at the sides as in "Pterocarya"). Cyclocarya Cyclocarya is a genus of flowering plants in the family Juglandaceae, comprising a single species Cyclocarya paliurus (qing qian liu or wheel wingnut), formerly treated in the genus "Pterocarya" as "Pterocarya paliurus". It is native to eastern and central China. It is a deciduous tree growing to 30 m tall. The foliage is similar to "Pterocarya", with pinnate leaves 20–25 cm long with five to eleven