The disease mainly spreads through root-to-root contact or through infested wood debris in soil, though there may be the possibility of spreading of the disease through the dissemination of basidiospores from fruiting bodies. According to literature, mature fruiting bodies of Phellinus noxius seldom form in nature, though their basidiospores may assist in the long range dissemination of the fungus. In Hong Kong, there were observations that fruiting bodies of Phellinus noxius produced massive basidiospores on infected trees. The prevalence of the fruiting bodies in this region remains unknown.