noun. The bark of various trees used as a source of tannin.

noun. Shredded bark from which the tannin has been extracted, used to cover circus arenas, racetracks, and other surfaces.

noun. The bark of the oak (or other trees) used as a source of tannin

noun. The spent bark used as a ground covering

noun. bark rich in tannin; bruised and cut in pieces to use for tanning; spent tanbark used as a ground covering

"The armory was only 200 feet by 100 feet with a concrete floor, covered in dirt and tanbark for the occasion."

bark  

age-blackened  age-darkened  black-barked  black-stained  broadspreading