the potential of microfossil use in paleodiet and paleoenvironmental analysis in northwestern ontario
abstract
historically wild rice was important economically and spiritually across much of central
and eastern canada, but the antiquity of its use by native communities is unclear. unlike plant
macrofossils, which have traditionally been used to identify this plant in prehistoric contexts,
silicophytoliths preserve well in archaeological sites and in carbonized food residue encrusted on
clay pots. this proxy, therefore, promises to yield considerable new insight into the antiquity
and intensity of wild rice harvesting in this region.
various phytolith types from various grasses, sedges and aquatic plants were examined.
however, the focus was kept on rondel phytoliths, a form only produced in grasses. thirty-eight
grass species were examined, including two species of wild rice (zizania aquatica and zizania
palustris). a minimum of three hundred rondels from each grass species were counted from
various parts of the plant including the inflorescence, the leaf and the stem. based on extensive
morphological comparisons of phytoliths produced by wild rice (zizania spp.), and other native
boreal and prairie grasses and maize (zea mays), several phytolith morphotypes were identified
that are produced only in wild rice (zizania spp.). in general, rondels with four spikes, with one
and three indentations, are characteristic of zizania (spp.). however, differences between the
two wild rice species were not established.
lake sediments from lulu lake in the lake of the woods area where modem wild rice
grows were analysed to determine if the types identified as being diagnostic of wild rice would
be present. as a preliminary analysis, the presence of wild rice (zizania spp.) can be identified
in small quantities in lake sediments. therefore, wild rice (zizania spp.) phytoliths can be a
powerful tool in the identification of the plant in holocene sediments.
potsherds with encrusted carbonized residues from the lake of the woods and
surrounding area were also examined for the presence of diagnostic wild rice (zizania spp.) and
maize (zea mays) phytoliths. these archaeological samples are attributed to the laurel (middle woodland), selkirk (late woodland), blackduck (late woodland), and sandy lake (late
woodland) cultures. based on the use of diagnostic phytolith types for both wild rice (zizania
spp.) and maize (zea mays), the presence ofboth these cultigens was identified in the residues of
all four cultures mentioned above.
this is the first time maize (zea mays) and wild rice (zizania spp.) have been positively
identified in prehistoric carbonized food residues from the boreal forest. based on pottery
types, wild rice (zizania spp.) and maize (zea mays) were consumed as early as the middle
woodland period (laurel phase). based on the samples examined, the evidence of maize (zea
mays) phytoliths in the residue is greater than those of wild rice (zizania spp.). however, this
might reflect sample bias or most likely biases due to processing of the plants before
consumption. therefore, the absence of a wild rice (zizania spp.) phytolith signature might not
represent that the plant was not consumed, rather that the parts of the plant with the diagnostic
phytolith types were removed before consumption.
maize (zea mays) horticulture during the late woodland period in the lake of the
woods and surrounding area does not seem likely because there is no evidence of gardening, or
heavy consumption of this plant. however, the latter might not be necessary for local
horticulture. in contrast, wild rice (zizania spp.) stands are common in the lake of the woods
and surrounding area, and therefore local harvesting of this plant is inferred.
collections
- retrospective theses [1604]