Maple Reproduction and Sap Flow at Harvard Forest since 2011

Seed production assures the persistence of tree populations and forest cover over the long-term, and so has long interested plant demographers and foresters. Many forest tree species produce seeds synchronously and at irregular intervals across large areas, a phenomenon known as masting. Initiated in spring 2011, this study addresses the mechanisms of mast seeding in sugar maple (Acer saccharum), and its impact on pollinators, seed consumers, and forest carbon dynamics at the Harvard Forest. We monitor seed production (via counts of seeds on trees), flower production, and resource status (via sap collection) on 20 trees. Pollination dynamics and seed predation (by weevils) were also monitored from 2012-2017. From 2015-2018, we monitored sap and seeds of red maple (Acer rubrum) trees to explore the hypothesis that this non-masting species would have muted dynamics compared to its masting congener.