The color that oak leaves turn in the fall can vary depending on the species of oak tree. Some oak trees turn a reddish-brown color that is especially rich on young trees, while others turn deep browns or copper colors, and some turn golden brown or yellow. Oak trees tend to have deeper shades of russet, red, and yellow-brown, and they tend to be the last holdouts in the fall, giving you color and interest in the landscape as the season transitions from late autumn to winter.