New Hampshire designated white birch (Betula papyrifera) as the official state tree in 1947. White birch is also known as canoe birch or paper birch (native Americans used white birch bark to make canoes and it was also used for writing paper).

Native to New Hampshire, white birch trees are found on the wooded slopes bordering lakes and streams in the state. White birch is a dramatic part of New Hampshire scenery - the birch's white trunk is a beautiful contrast against the green / brown / grays of other trees.

Sturdy and graceful, the white birch tree can reach a height of 80 feet. The bark is chalky to creamy white, with a yellow tinge, and peels in thin film-like layers. White birch leaves are broad and oval in shape on short, sturdy leaf stalks.

Source:

State Tree: New Hampshire Almanac

Links:

State Trees - 50 States List