Identifying characteristics:
Also named Betula lutea, this birch usually grows to 60 or 75 feet
tall, but may reach 100 feet. It has an irregularly rounded crown and wide-spreading
branches with pendulous tips. Maturity is reached at about 150 years, but
trees can live to 300 years. Leaves
are simple, 3 to 5 inches long, sharply doubly toothed, with rounded
or heart-shaped leaf bases. They are alternately arranged on twigs, but
paired on spur shoots. Leaf surfaces are a dull, dark green above, and pale,
yellow-green below, with hairs in the vein axils. Fall color is bright yellow.
Flowers are produced in separate
catkins on the same tree in spring, before or with the leaves. Male flowers
occur in drooping catkins and female flowers in shorter, erect to nearly
erect catkins. Fruits are tiny,
narrowly-winged nutlets borne on hairy, 3-lobed bracts in broad, erect,
short-stalked, conelike catkins. The catkin axis and scales often persist
on the tree into winter. Ovoid buds are covered with 3 or 4 chestnut-brown,
often hairy scales. Spur shoots have terminal buds. The light-gray or golden
bark is smooth on young trees,
becoming dirty yellow-gold and separating into thin, papery shreds and breaking
into ragged plates as the tree matures.
Similar species:
Ecology:
Distribution: The yellow birch is the provincial tree of Quebec
and occurs in southeastern Canada, the northeastern US, south to the high
peaks of Georgia and Tennessee. It is native to the extreme northeast corner
of Iowa and along the Iowa River in Hardin county.
Habitat: This birch prefers moist, cool soils and cool summers. It grows along lakes, swamps and stream banks in the north and on the sandy, loam soils of upland slopes and ridges in the mountains. Further south it requires cool, north-facing slopes and slopes bordering streams. It is a slow grower and is moderately shade tolerant and susceptible to birch borers when planted outside its native habitat. It is subject to anthracnose disease of the foliage and canker of the twigs and branches.
Uses:
Wood: Although too scarce in Iowa to be of any commercial importance,
it is a valuable hardwood in the northeastern US and southern Canada. The
wood is hard, heavy, strong, shock-resistant, close-grained and takes
a fine polish. It is used for cabinets, furniture, flooring, doors, veneer,
paneling and tool handles. The papery bark burns easily even when wet. The
young twigs and inner bark are a source of wintergreen oil, but the yield
is less than that of the sweet
birch (B. lenta).
Wildlife: This species is of only moderate value to wildlife. Rodents and small birds eat the tiny seeds.
Horticulture: The yellow birch is not used very much in landscaping as the white-barked birches are often deemed more attractive. It is less adaptable than many other birches and is not recommended for use in Iowa with its hot, dry summers.
