Taphrina pruni 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 of the fruit (sloes), producing swollen on one side, otherwise deformed and flattened fruit gall without a stone. The twigs on infected plants may also be deformed with small strap-shaped leaves. "T. pruni" produces a distinctive tongue-like growth, similar to other closely related species such as "Taphrina alni" on Alder ("Alnus glutinosa") and "Taphrina padi" on Bird Cherry "Prunus padus". The growth is the distorted fruit and not a fungus in its entirety. "T. pruni"
Prunus ursina It is usually present in too small a quantity to do any harm but any very bitter seed or fruit should not be eaten. Consumption of small quantities of hydrogen cyanide stimulates respiration and improves digestion. Excessive consumption of the toxin can cause respiratory failure and death. "Prunus ursina" fuits better in full sun but is still successful in partial shade. The tree will form suckers if its shallow roots are damaged. Among the pests that affect the "prunus" genus is honey fungus. the seed requires 2–3 months cold stratification in order to germinate. Prunus ursina Prunus ursina (bear's plum,