How is P. ramorum spread?
Researchers are studying how P. ramorum spreads. The pathogen has been isolated from host debris (e.g. firewood and leaves), nursery stock, soil, stream water and rain-splash. Human movement of infested host materials is considered the most likely means of long distance spread. Infested soil and water-splash may contribute to local and/or tree-to-tree spread of the disease. Researchers are also investigating insects and birds as possible vectors for this disease.
