Red band needle blight of conifers in Britain

Red band needle blight is an economically important disease affecting a number of coniferous trees, in particular pines. The disease has a world-wide distribution but until recently it was mainly of concern in the southern hemisphere. In much of the world, including Britain, it is caused by the fungus Dothistroma septosporum. Red band needle blight causes premature needle defoliation which results in the loss of timber yield and, in severe cases, tree mortality. Since the late 1990s the incidence of the disease has increased dramatically in Britain, particularly on Corsican pine (Pinus nigra ssp. laricio), and due to the extent and severity of the disease on this species, there is now a five-year planting moratorium of it on the Forestry Commission estate. More recently there have been reports of the disease causing damage to lodgepole pine in Scotland and it has also been reported on Scots pine – although it rarely appears to be causing significant damage to this species. Reasons for the increase in disease incidence are unclear but could be due to increased rainfall in spring and summer coupled with a trend towards warmer springs, optimising conditions for spore dispersal and infection. Such conditions may become more prevalent in Britain over the next 20 years if current trends in climate change continue. In Britain disease management is currently focused on silvicultural measures to reduce inoculum loads and the use of alternative, less susceptible species in future rotations.