EVALUATING RECORD-WEATHER-INITIATED ROOT EXPOSURE AND EROSION AT A RECREATION SITE, GRASSE RIVER, CANTON, NY

A cut-bank exposure along the Grasse River in Canton, NY, on St. Lawrence University campus, is a favorite warm-weather play spot for students, includes two rope swings and a small beach (0.25ha). Concentrated use has caused sediment erosion and root exposure beneath the trees adjacent to a beach and hillside leading to exacerbated, large-scale sheet erosion. This erosion is intensified by rain, snowmelt and foot traffic, which makes roots more susceptible to temperature fluctuations and, thus, anatomical changes. Using the methods of Gartner (2006) and Corona et al. (2011) we quantified root exposure by growth and/or erosion and estimated erosion rate. Root samples (n=8) were exposed and in contact with the ground, with bark on the uncovered portion. Approximately 2cm-wide root cookies were taken at least 1.0m from the bole of select Eastern white pines (Pinus strobus) using a wire saw. Samples were dried overnight at 55^oC, and then prepared for microscopic analysis by progressive sanding/polishing. Root rings were dot counted for age, and six, representative, terminal earlywood tracheid-width measurements were taken per ring using Leica V3.7 imaging software. When selecting a year of exposure, we used the year of greatest, consistent change between tracheid widths and was corroborated with a transition to narrower ring widths. The mean exposure year for these root samples was 2013. This exposure is almost certainly the result of intense usage by students (and locals) in response to the nearly continuous record high temperatures (+4^oC departure from normal) and record dryness (-4.6cm departure from normal) for the month (15APR-15MAY13) preceding the closing of campus for the academic year. We estimate that over 120m³ (e.g., 12 dump truck loads) of alluvial sands have been lost from the active area since 2013. Despite signage stating, “no access,” as the only beach area on campus, there is little to be done to prevent future losses from this popular play spot. Seemingly, if weather records continue to be surpassed then localized and subtle, weather-related impacts like these will become more common.