It is known in different regions as bur oak, mossy cup oak, overcup oak, scrub oak, and mossy cup white oak. Bur oak is a name suggested by the acorn which has a fringe round the cup like a bur. This is the oak which gave name to James Fenimore Cooper’s book, “Oak Openings” a romance of early days in Michigan. Oak openings were areas where fires had killed the old timber, and a young growth had sprouted from stumps and roots, or had sprung up from seeds buried in the ground beyond the reach of the fire. Some of those tracts were very large, and they were not confined to any one state. They existed in Michigan, Wisconsin, Minnesota, Dakota, and elsewhere. Bur oak, because it is a vigorous species, was able to take possession of such burned areas, to the exclusion of most others. Few American oaks have a wider range. It extends from Nova Scotia to Manitoba, and in the United States is found in most states east of the Rocky Mountains. It extends farther west and northwest than any other commercial oak of the Atlantic states. In a range of so great geographical extent the bur oak finds it necessary to adapt itself to many kinds of land. It prefers low tracts where water is sufficient but not excessive, but it grows well in more elevated situations, provided the soil is fertile. It is not a poor-land tree. In the primeval forests it attained largest size in Indiana and Illinois. The largest trees were from 150 to 170 feet high and four to seven in diameter. Sizes varied from that extreme down to the other extreme near the outskirts of its range where the growth was stunted. Large quantities of very fine logs have been cut from trunks from two to four feet in diameter, and forty to sixty feet to the limbs. The leaves of bur oak are from six to twelve inches long, simple and alternate; the petioles are thick with flattened and enlarged bases; the leaves are wedge-shaped at the base, and have from five to seven long, irregular lobes, the terminal one very large and broad. They are dark green in color, and are smooth and shiny above, silvery white and pubescent below. The edge of the leaf is notched somewhat like chestnut, but the teeth or notches are not so sharp. The twigs are provided with corky wings, or flattened keels of bark, along their sides. Some of the wings are an inch or more wide. They are apt to escape notice when the tree is in leaf, but in the winter the bare twigs look rough and ragged. The weight of bur oak is approximately the same as white oak, and the two woods are much the same in strength and elasticity. The bands of summerwood are broad and dense, and the springwood is filled with large pores. The medullary rays are broad, but not numerous in comparison with white oak. They are sufficiently conspicuous to show well in quarter-sawing.