hazelnut leaves are damaged by parasites and rot diseases. pests and hazelnut garden protection concept

abstract affected avellana background chasmothecia cleistothecium close closeup color common corylus damaged detail disease diseased dry erysiphaceae focus fungal fungi garden green growth guttata hazel hazelnut illness infection leaf macro mildew natural nature old organic pathogen pathology pattern phyllactinia phytopathology plant powdery selective spot spring texture tree veining white