Another issue with oaks, worth mentioning. There are two major oak "groups" in the U.S.; the red oak group and the white oak group. They are actually pretty easy to tell apart. Red oak group has leaves with pointy ends, white oak group has leaves with rounded ends. The acorns from the white oak group are sweeter and better for eating than are those from the red oak group, which are very bitter.

Squirrels don't care, but native peoples who have used acorns for food for centuries knew this.