Usually oak trees leaves are a dog-poo brown. They either stick to the tree until spring when the green leaves appear or they fall on the grown in a hideous ground cover color, although great for hiding the fact you are too lazy to pick up…
anyway, this leaf must have been green & gone into complete shock to be wet & then frozen, thereby turning into a dazzling display of color. I don’t like oak trees. Their leaves look like dog poop.