See:
Peach (Prunus persica) - Leaf Curl
Cause Taphrina darkeri, a fungus that may be locally epidemic, has been reported from Oregon on vine maple and Idaho on Rocky Mt. maple.
Symptoms Dark, irregular blisters appear on the upper surface of infected leaves. Spore production forms a white bloom on the affected tissues.
Control Generally not significant enough a problem to warrant control.
Reference Mix, A.J. 1949. A monograph of the genus Taphrina. University of University of Kansas Science Bulletin 33:3-167.