Have you noticed lately that your peach leaves appear curled or puckered? Do leaves appear to be lighter than normal, flushed with red, blistered, distorted, and curled? Chances are your tree has peach leaf curl, a fungal disease caused by Taphrina deformans. Although peach leaf curl is primarily a disease of peach, nectarines are also affected. Peach leaf curl is first noticed in spring when young leaves start to emerge. The entire leaf or a portion of it may appear crinkled and curled with flushes of red or purple . Later on in the season, the fungus begins to produce spores and leaves appear silvery or powdery gray. Infected leaves turn yellow and brown and fall off the tree and are replaced by a new set of foliage. Flowers, young fruits and stems may also be infected. Affected fruits are distorted with wrinkled, discolored areas on the surface. Extensive defoliation may affect fruit yield the following year and may also predispose the tree to winter injury and other diseases.
Plum pocket is a disease in plums caused by Taphrina communis. Leaf symptoms are similar with peach leaf curl and the plums appear to be distorted, wrinkled, and puffy. This disease is not considered a serious problem in most commercially cultivated plum varieties.
Control measures for both diseases can be controlled effectively with a single fungicide application. Apply the fungicide before the buds swell and during the dormant season usually from fall to late winter. If buds have begun to swell or open, it is too late to control the disease. Fungicides registered for control of peach leaf curl and plum pocket include Bordeaux mixture, chlorothalonil (Daconil, Bravo 720), liquid lime-sulfur, ferbam, and other copper-based fungicides.
This article originally appeared in the June 13, 1997 issue, p. 90.