Birch Trees of New Hampshire
Birch is thin-leaved deciduous tree that belongs to the family Betulaceae. It requires well-drained soil, moisture, and direct sunlight for the proper growth. Birch is known as pioneer species because it easily populates habitats destroyed by fire. This plant is mainly cultivated because of its ornamental value and high-quality wood.
New Hampshire has 6 native species of Birch:
- Paper birch or white birch Betula papyrifera – NH’s State Tree
- Yellow birch Betula alleghaniensis
- Sweet birch or black birch Betula lenta
- Heart-leaved paper birch Betula cordifolia
- Gray birch Betula populifolia
- River birch Betula nigra (Rare in NH)
- Birch is a medium-sized tree that can reach 30 to 50 feet in height. Some species may grow to 80 ft.
- Birch have green leaves that are oval or elliptical in shape. Leaf edges are single or double serrated.
- Bark of the birch can be white, grey, yellow, silver or black. Young trees have smooth bark. Deep ridges on bark are characteristic of older plants. Bark of all birch species (except Grey Birch) peels off in long horizontal strips.
- Birch has shallow root system which can damage sidewalks and roads in urban areas.
- Individual flowers are arranged in long clusters known as catkins.
- Birch produces fruit called “samara” which can release 1 million seeds each year.
- Birch wood is highly flammable. It can catch a fire even when it is wet.
- Birch trees can live from 30 to 200 years, depending on the species, quality of the soil, and climate.
Birch Trees of New Hampshire
Short-lived species, named for its thin white bark. Typically reaches 66 feet, grows with a single trunk, but may develop multiple trunks or branches close to the ground. Leaves are dark green & smooth, alternately arranged on the stem, oval to triangular in shape, 2–4 in. long and about 2⁄3 as wide. The leaf is rounded at the base and tapers to an acutely pointed tip.
Reaches 60–80 feet, long-lived, typically 150 years. Some old growth forest specimens may last for 300 years. The bark on mature trees is a shiny yellow-bronze. Leaves alternate on the stem, oval in shape with a pointed tip, & often a slightly heart shaped base. They are 2–5 in. long and typically half as wide, dark green on the upper side, lighter on the bottom.
Sweet Birch or Black Birch
Medium-sized, reaching 50 to 80 feet. The twigs, when scraped, have a strong scent of wintergreen. Leaves are alternate, ovate, 2.0–3.9 in long and 1.6–3.1 in broad, with a finely serrated margin. The oldest known B. lenta has been confirmed to be 368 years old. Sap can be boiled the same as maple sap, but its syrup is stronger (like molasses). It can be used to make birch beer.
Heart-Leaved Paper Birch
Reaches heights of about 80 feet Mature bark is white or bronze-white, peeling in thin layers. Leaves are alternate, ovate, 2.5-5 in. long, and double-toothed. The leaf base is generally cordate (heart-shaped).
Prefers poor, dry upland soils, but is also found in moist mixed woodlands. Living only about 30 years, it is a common pioneer species on abandoned fields & burned areas. Leaves are 2-3in. long by 1.5-2.5 in. wide, alternately arranged, ovate, with elongated tip. They are dark green above & paler below. Bark is chalky to grayish white with black triangular patches where branch meets trunk.
River Birch (uncommon in NH)
Grows to 80–100 ft. The base of the tree is often divided into multiple slender trunks. Leaves are alternate, ovate, 1 1⁄2–3 1⁄4 in long & 1 1⁄4–2 1⁄4 in broad. Upper surface of the leaf is dark green in color, underside is light yellow-green. It’s found along stream-sides & in forested wetlands & floodplains.