Taphrina pruni being larger than the healthy one. As a fungus, cool and wet weather conditions promote the germination of spores, whilst warm and dry weather results in infection rarely taking place. Colonisation can become extensive and eradication very difficult. The disease can to some degree be controlled by carefully removing infected branches, witch's brooms and fruit before the infective air borne spores are produced. Applications of copper-containing fungicides have a degree of control over the fungus. Taphrina pruni Taphrina pruni is a fungal plant pathogen of blackthorn (Prunus spinosa) that causes the Pocket or bladder Plum gall, a chemically induced distortion
Prunus × cistena Prunus × cistena Prunus × cistena, the purple leaf sand cherry or dwarf red-leaf plum, is a hybrid species of prune-cherry, the result of a cross between "Prunus cerasifera" (cherry plum or myrobalan plum) and "Prunus pumila" (sand cherry). A leggy bush or shrubby tree, it typically reaches a height of 1.5–2.5 meters and has a useful life of 10–20 years. The fruit are edible, if strong-tasting. Some people make jams or preserves from them. It is not advisable to eat the pits. Frost-tolerant, purple leaf sand cherries can be grown up to USDA Hardiness Zone 2. Commercial specimens are