Reconstruction of woodland vegetation and firewood exploitation in Nine Mile Canyon, Utah, based on charcoal and pollen analysis

Anthracological (charcoal) and pollen analysis conducted on samples from multiple sites in Nine Mile Canyon, Utah, western United States of America, were used to reconstruct the woodlands of this region and interpret firewood exploitation during the Formative period (∼ AD 200-1300). The pollen record identifies constituents of the paleoenvironment of this region, reflecting species that grew in the vicinity of the site and in the broader area. Wood charcoal reflects various trees and shrubs that were used as fuel or for construction by the prehistoric occupants settled in Nine Mile Canyon. Pollen results elucidate a portion of the spectrum of wood taxa, which varies in different parts of the canyon, depending on elevation and the canyon's topography. While micro-charcoal analysis has a long and rich tradition in association with pollen analysis, anthracological analysis is different in that it focuses on macroscopic pieces of archaeological charcoal. Here, anthracology, using SEM imagery, helps define local woody taxa by identifying macroscopic pieces of archaeological charcoal. These two analytical tools build a complementary record of local woodland vegetation through aerial pollen transport and fuel wood selection. While the pollen record is affected by aerial transport, the anthracological assemblages, in most cases, reflect species growing in the vicinity of the prehistoric settlements, but can be affected by natural transport within the drainage. Recovery of Douglas-fir (Pseudotsuga menziesii) charcoal from the lower portions of the canyon, containing steep walls and natural conditions not favorable for Douglas-fir growth, indicates presence of drift-wood or debris-flow deposits.