Mast is a collective term for seeds and fruit produced by trees and shrubs, and the amount that is produced varies from year to year. Each year can be quite different based on the availability of nutrients, the weather, predators, and more. A mast year is one in which there are mass amounts of mast. We still don’t know why plants have these banner years. Studies have shown that stressors like a spring frost, or a summer drought, can cause mast seedings. This leads to a common theory that these plants are overproducing seeds when they are stressed, in a last ditch effort to make sure they get as many copies of themselves out there as possible. This year is not a mast year, at least not for our oaks, so there are not many acorns on the ground. ~ Maine Audubon Staff Naturalist Doug Hitchcox