Oak tree dropping leaves and acorns


Our twenty year old red oak is dropping small branches of 6-20 leaves all day and hundreds of acorns. Is there a problem I should be dealing with? Thanks


Thank you for contacting the Toronto Master Gardeners.

At this time of year the most likely culprit responsible for what you are observing are squirrels. A squirrel’s main diet consists of nuts, seeds and, of course, acorns. Examine the branches, if the twigs have a slanted cut end or a sheared-looking end, then the squirrels are your culprits. They bite the stems to use the leafy twigs to make their nests called dreys for winter. I have a 38 year old white oak tree and spend an hour everyday sweeping up the branches and fallen acorns that have been left behind by hungry squirrels.

There are  two major groups of oaks, red and white and each have seeds (acorns) that differ in their chemical makeup. Red oak acorns are rich in fats but are laced with tannins, whereas  white oak acorns are less fatty and lower in tannins. As a result , researchers found that in those red oak acorns that were eaten, frequently only the top half the end which contains the tasty fats are eaten, whereas the bitter-tasting tannins found near the end that contains the embryo are frequently left on the ground.

Fear not, the squirrels will not  kill the tree, but they may make it slightly bushier with their “pruning.”