Recent research has greatly increased our knowledge of early human impacts on the environment. Records of fossil charcoal and chemical elements from a bronze smelting site at Huoshiliang, in the Hexi corridor of northwest China, provide material with which to estimate the extent of smelting activity and its impact on the environment. Analysis of the microstructure of wood fossil charcoal is used to identify the types of charred wood and to reconstruct the local vegetation present during the period of smelting. Four wood types were used as firewood for smelting: Tamarix, Populus, Salix, and Polygonaceae. The assemblages of fossil charcoal showed that Tamarix was the most dominant shrub and was widely used as firewood, as a percentage of charcoal it increased from 89% to 97% over the smelting period.