Linda Williams, forest health specialist, Woodruff, Linda.Williams@wisconsin.gov, 920-360-0665 

Have you noticed any oaks looking kind of red this spring? Or maybe you’ve noticed that the leaves at the tips of the branches are looking red or maroon? 

From a distance some oaks have a red hue, probably due to a prolonged and cool spring.

Oak trees that are displaying reddish leaves this summer are just responding to weather events from this past spring while they’re also putting on new growth. Generally the reddish coloring of new leaves disappears quickly in the spring as the leaves finish expanding, but this year, perhaps because of some late frost/freezes and the prolonged cool spring weather, the leaves maintained that slight reddish color well into June. Many oaks also sent out a second flush of leaves as growth continued, and those leaves were also a reddish color.

Looking closely at the leaves, you can see that the color is natural and not due to damage from insect or disease.

We saw a similar issue in the spring of 2014. That spring was a long cool wet spring, and oaks in several areas, especially in the north, had reddish leaves through late June. By late July the reddish color had disappeared, and the trees didn’t appear to be adversely affected.