Phytoliths and taphonomy
the Contribution of Experimentation
to the Quantification of Phytoliths in Wood Ashes
Ashes, the mineral residues of wood combustion, contain siliceous particles that can be preserved for long periods in archaeological sediments. Phytoliths can thus be useful indicators of combustion activities whose biodegradable or soluble remains have disappeared.
In this paper, an experimental evaluation of the potential of phytoliths for the quantitative and qualitative analysis of carbonized ligneous biomasses is presented. The results show: 1) that only a very small portion of ash is capable of resisting dissolution phenomena, 2) that phytoliths originating from ligneous tissues are only slightly characteristic from a taxonomic perspective, and 3) that it is not possible through a routine microscopic analysis to differentiate phytoliths derived from combustion and phytoliths liberated following a slow decomposition of organic material. It thus appears that strong concentrations of “wood” phytoliths can be an indicator of combustion, but that phytolithic analysis does not allow taxonomic identification of the ligneous combustible or evaluation of the quantity of biomass burned.