P. cinnamomi was recovered by lupine baiting from soil particles carried on boots, tires, vehicles and feral pig hoofs. It existed in soil as chlamydospores and unknown propagules in organic matter. Zoospores of P. cinnamomi that were released when soil was submerged in water were dispersed by rain splash or runoff water. The fungus was trapped by lupine [Lupinus angustifolius] from streams and recovered from dead ohia [Metrosideros collina spp. polymorpha] leaves on the forest floor. It was isolated from the roots of 20 endemic, 2 indigenous and 5 introduced plant species in 22 plant families. All isolates tested were of the A2 mating type.