Click on the images help you identify a bur oak.
Form
Under favorable conditions, bur oaks can reach 80 feet or higher, with a trunk diameter of 36 to 48 inches or more. Under unfavorable conditions, they are shorter, with gnarled branches covered in corky tissue. In dense forests, the trunk is straight with short branches. In open conditions, bur oaks have broad tops of heavy, spreading branches and a relatively short trunk.
Bark
Thick and deeply furrowed, with irregular, plate-like broken scales often slightly tinged with red. Outer bark may slough off in areas affected by harmless fungi.
Leaf
Leaves are simple, alternate on the stem, and 6 to 12 inches long. Several leaves grow from the ends of twigs. Leaves have a pair of deep indentations near the base and wavy notches on the broad middle and upper portions. Summer color is shiny dark green, turning yellow, brown, and rusty red in autumn.
Fruit (seed)
Acorns are set deeply or almost enclosed in a fringed cup, with diameters of 1 inch or more. Size varies widely. Seeds are bitter.
Range
One of the most common trees in Minnesota, bur oaks extend into the western prairies. They usually grow singly in open stands and fields. Extremely drought-tolerant, they favor moist, well-drained soil. Adapted to periodic fires, especially in savanna areas. Easily propagated but slow-growing. Moderately shade-tolerant.
Wood uses
Wood is heavy, hard, strong, tough, durable, and rich brown. It is used for furniture, interior finish, flooring, structural material, and railroad ties.