Lily Lake

Vegetation History

During the period between 1200-690 cal. yr BP at Lily Lake, red pine (Pinus resinosa), jack pine (Pinus banksiana), and oak (Quercus spp.) were the dominant species. Oak continued to rise in abundance until 840 cal. yr BP, when red and jack pine became the dominant species. Around 700 cal. yr BP, white pine (Pinus strobus) pollen increased while red and jack pine decreased. Between 690-80 cal. yr BP white pine increased to approximately 30% and remained relatively constant until post-settlement. Jack and red pine, as well as ironwood (Ostrya spp.), percentages decreased after settlement. White pine sharply decreased and ragweed (Ambrosia spp.) pollen sharply increased post settlement. Oak increased dramatically in surface samples.

Fire History

Total charcoal was higher at Lily Lake than other sites in the sand plains region, with an average fire return interval of approximately 72 - 88 years. Before 575 cal. yr BP, charcoal influx rates were relatively high and high peaks of charcoal occurred one to two times per century. After 575 cal. yr BP, both charcoal totals and frequency of peaks decreased. At the 700 cal. yr BP mark there is a large charcoal peak that coincides with jack-red pollen decrease and white pine pollen increase. Incidence of grass charcoal was high throughout the core. At Lily Lake, charcoal signatures changed at approximately 1000 cal. yr BP, where there was a decrease in magnitude and frequency of charcoal peaks.