Black oak (Quercus velutina)
Height 35' to 75' with a diameter of 9" to 30"; clear trunk for 20' or more on large trees; crown wide and irregularly shaped.
On young trees, smooth and dark brown; thick and black on older trees with deep furrowed and rough broken ridges; inner bark bright yellow and bitter because of tannic acid.
Simple, alternate on stem, length 5" to 10"; lobed halfway to midrib with seven to nine triangular, bristle-pointed lobes; crimson in spring, silvery when half grown, brown in autumn; when mature, thick dark green and shiny on upper surface and pale on lower surface; covered more or less with down; conspicuous rusty brown hairs in forks of veins.
Light brown nut (acorn) matures in the second season; length 1/2" to 1"; shape somewhat round; one-half to three-fourths of nut is enclosed in thin, dark brown, scaly cup; kernel is yellow and extremely bitter.
Found in southeastern Minnesota on dry ridges; moderately shade intolerant, moderately fast growing.