Volutella necrosis

Volutella necrosis, caused by the fungal pathogen Volutella albidopila, is a common and destructive plant disease that targets the bark and vascular tissues of woody ornamentals. By interfering with the plant's ability to transport nutrients, the fungus causes systemic damage that can lead to rapid branch dieback and even total plant mortality.

This pathogen is particularly problematic for dense-canopy shrubs and hedges, such as boxwood. The fungus behaves as an opportunistic parasite, often infiltrating plants through mechanical damage, winter injury, or insect feeding sites, effectively colonizing the bark tissue and producing its characteristic fruiting bodies on the surface.

Early diagnosis is vital for effective management. Infected plants typically exhibit localized browning or reddish discolouration of the bark, which eventually cracks and scales off. In humid conditions, small white or cream-coloured spore masses appear on the affected areas, and the associated foliage often wilts, turns yellow, and begins to drop prematurely.

The spread of Volutella albidopila is highly dependent on environmental factors, particularly moisture and temperature. Spores are easily disseminated by water splashing, wind, or improper handling of pruning equipment. High humidity and poor air circulation within the shrubbery significantly accelerate the disease's progression during the spring and autumn months.

Management strategies focus on a combination of cultural practices and chemical intervention. It is essential to prune out all dead or infected branches at the first sign of symptoms, ensuring that tools are disinfected between cuts to prevent spreading the spores. Maintaining plant vigor through proper fertilization and providing adequate spacing to improve airflow are key to preventing future outbreaks.