Bur OAK Mossycup Oak
Blue oak Quercus macrocarpa Z
3-8 H 70' W 50'
Habitat. Bur Oak tolerate a wide
range of soils but prefers moist soils. Well-adapted to alkaline soils, poor
drainage, and high clay content, Bur Oak is also very drought-tolerant. Bur
Oak grows best in full sun. Bur Oak will adapt to various soils where other
Oaks sometimes fail but is difficult to transplant from well-drained soil
due to the tap root.
Leaves. Since it is in the
white oak family thebur oak leaves are 6-12"
long, oval, 5 to 7 lobed. The upper surface is lustrous, dark green; lining
silvery pubescent. Deeply lobed in the middle.
Flowers. Flowers in May, staminate in profuse,
clustering slender, hairy catkins 4-6" long with opening leaves.
Fruit. Bur oak fruit ripens autumn of first
year. Acorns are 1/2 to 2 inches long, fuzzy, in deep brown hairy cups,
annually, kernels are white & sweet. Largest of the oak acorns.
Winter Buds. Terminal bud is 1/8th inch long,
reddish brown and oval hairy and blunt.
Bark. The bark is gray-brown, deeply fissured, shaggy; branches
ridged, shedding plates of bark; twigs stout, pubescent, and winged with
Wood. The wood of a bur oak is
brown, closely grained, heavy, hard, tough and durable with conspicuous pith
rays, used as the highest grade of white oak in the lumber trade. Excellent
Pests. Many caterpillars feed on Bur Oak
but only the gypsy moth is a serious pest. Cottony maple scale is
occasionally found on bur oaks These insects overwinter on the branches as
Distribution. They are native
from Nova Scotia to Montana; south to Pennsylvania, Tennessee, and Texas.
Other. Bur Oak also called Mossy Cup Oak has an
average growth rate for an Oak, maturing with a broad round crown, leaves
turning an attractive copper-yellow in fall. Maximum height is 165'. Bur Oaks can be difficult to transplant because
of the deep taproot. The tap root dominates the root system on young trees
growing in well drained soil. If you are planning to buy Bur Oaks for landscape sales
we highly recommend our
root growing bags for easy transplanting as the Bur Oak tap root can not
penetrate the bag..