black oak: medium to large deciduous timber tree of the eastern United States and southeastern Canada having dark outer bark and yellow inner bark used for tanning; broad five-lobed leaves are bristle-tipped
tree: a tall perennial woody plant having a main trunk and branches forming a distinct elevated crown; includes both gymnosperms and angiosperms
chalk: a piece of calcite or a similar substance, usually in the shape of a crayon, that is used to write or draw on blackboards or other flat surfaces