Weather Tidbits: Mast Years For Oak Trees

We’ll be discussing mast years for oak trees in this edition of Weather Tidbits. If you have an oak tree in your yard, you may have noticed that some years the tree will drop more acorns during the fall season than others years. There is a folklore that the overproduction and high drop of acorns means that a harsher and snowier winter is coming. That is false! The oak tree is simply just in its mast year. Mast is basically the fruit of a plant. In this case, acorns from oak trees. A mast year is when a plant produces more fruit than usual. For oak trees, usually every 2 to 5 years. The exact cause is not known, but weather in the spring and summer can have contributing factors. For example, a late spring frost may limit acorn production. Acorn production can be so high during a mast year that squirrels and other wildlife cannot keep up. So, mast years help balance out wildlife consumption of acorns and offspring reproduction of other oak trees, which is necessary in the woods to keep the oak tree species going.