Institution: UVM Maple Extension

According to a recent survey of more than 300 maple producers in the northeast United States, nonconductive wood was hit during tapping on average 4.5% of the time and the responses ranged from 0-41% of the time (UVM Extension 2019 unpublished). Previous research has explored factors that impact the likelihood of tapping into NCW. Significant factors include but are not limited to; dropline length, taphole diameter, tapping intensity (number of taps/tree) and stem growth (van den Berg and Perkins 2014). Other work touched on the relationship between the amount of conductive wood exposed while tapping and yields (Wilmot et al. 2007). But to date, there has been no direct investigation as to the relationship between the percent of NCW is intercepted while tapping and sap yield. The present study sought to understand the relationship between the amount of NCW in a given tap how and the amount of sap collected, as well as understanding if other factors (sap sweetness) might impact total yields between treatments.