A Promising Fall Beechnut Crop
Beechnuts, high in protein and fat, are the primary fall and winter food for many forest wildlife species including Red, Gray and Flying Squirrels, Eastern Chipmunks, Black Bears, Blue Jays, Tufted Titmice, Wild Turkeys, and Ruffed and Spruce Grouse. The dependence of these animals on this food source makes them vulnerable to the American Beech’s cyclical nut production.
In the Northeast, American Beech (Fagus grandifolia) mast crops (amount of beechnuts produced by beech trees) have a two-year cycle: one year they produce an overabundance of nuts and the following year very few. Among other animals, Black Bears rely on these nuts to sustain themselves over the winter. That a bear’s nutritional health affects its reproductive health was documented in a study in Maine that showed that the mean proportion of female bears producing cubs decreased to 22% when a denning period followed a poor beechnut crop. During denning periods following good beechnut production, 80% of the productively available females produced cubs.
Many American Beech trees in the Northeast suffer from Beech Bark Disease which has seriously compromised their ability to produce nuts. Invasive scale insects (Cryptococcus fagisuga) invade a tree. Through a presently unknown mechanism, excessive feeding by these insects causes two different fungi (Neonectria faginata and Neonectria ditissima) to produce annual cankers on the bark of the tree. This disease decreases nut production, and eventually lesions around the tree girdle it and causes the tree’s death. The diminishing number of healthy beech trees will have a significant effect on consumers of beechnuts as well as a broad array of other organisms.
Naturally Curious is supported by donations. If you choose to contribute, you may go to http://www.naturallycuriouswithmaryholland.wordpress.com and click on the yellow “donate” button.