The Forestry Commission has published a very useful summary of the spread of P. ramorum into larch trees and the measures that are being taken to control this spread. It appears that the disease is targeting rhododendron and larch trees at present and that the report of its spread into sitka spruce has so far proved to be inconclusive.
The spread of the disease into heathland species has so far been restricted to a small area of blaeberry. Heather has been shown to be at risk in laboratory tests, but so far the disease has not been seen on heather in the wild. This remains the nightmare option.