A Technical Report from The Bartlett Tree Research Laboratories
Oak leaf blister fungus (Taphrina caerulescens), also known as the Tongue Fungus, affects around 50 different species of oak globally. Within the UK and Ireland the Evergreen oak (Quercus ilex) is especially sensitive. This family of fungi are also responsible leaf blistering, witches broom and leaf curl of several other tree genera. Oak leaf blister fungus arrived in the UK five-eight years ago and is becoming more prevalent and severe on an annual basis.