Phytolith Analysis of Samples from Voyageurs National Park, Minnesota

Seventy-six plant samples and forty sediment samples from voyageurs National Park were analyzed for phytoliths. Leaf, stem, root, inflorescence, and where possible, seed phytoliths were extracted from each plant sample as a key against which sediment phytoliths could be compared.

All phytoliths were examined by light microscopy using a research petrographic microscope equipped with a Nomarski Differential Interference Contrast (DIC) system. Some phytoliths were also studied using a Scanning Electron Microscope (SEM). As can be seen from Figures 1-8 the SEM is far superior as an analytical and identification tool.

A computer program was used to assign sediment phytolith assemblages to the plant(s) most likely to have been the source of these biosilicates. Hierchloe odorata (sweet grass) leaf appears to be an important component of every sediment phytolith assemblage. Zizania aquatica (wild rice) constituted a significant part of two sediment samples.

Although many aspects of this study were of a preliminary nature, there is every indication that systematic phytolith work on relevant plant species will be of value to archaeological reconstructions.