Current polypore

The current polypore, known scientifically as Phellinus ribis, is a wood-decaying fungus that acts as a serious pathogen for various berry-producing shrubs. It is a perennial fungus that primarily attacks the base and stems of the host plants, causing a slow but lethal structural deterioration of the woody tissues.

The primary hosts for Phellinus ribis are species within the Ribes genus, most notably currants (black, red, and white) and gooseberries. While it is rarely found on other woody plants, its presence in a garden setting is highly specific to these berry shrubs, especially in older or neglected plantations where canopy cover is too dense.

Symptoms of the infection typically manifest as hard, shelf-like fruiting bodies appearing near the base of the plant or on the lower stems. These structures are leathery to woody in texture and range in color from brown to dark rust. As the fungus consumes the lignin and cellulose, the infected stems lose their vigor, leaves may wilt or yellow prematurely, and the wood becomes brittle, eventually leading to the death of the entire branch.

Development and spread of the disease are heavily influenced by environmental factors such as high humidity and the presence of wounds on the bark. The fungus enters the plant through cracks, insect damage, or improperly made pruning cuts. Once established, it grows internally, making it difficult to eradicate with external chemical treatments alone.

Management of the current polypore requires a combination of strict sanitation and cultural practices. It is crucial to identify and prune away any infected stems, ensuring all diseased material is burned to prevent further spore distribution. Proper spacing and airflow are essential to keep the lower stems dry, thus discouraging the germination of fungal spores. In cases of severe infestation, removing the entire plant is the most effective way to protect the rest of the garden.