Until recently, the known distribution area of P. lateralis was limited to Washington, Oregon, and California where it mostly occurs.

In 2009, the pathogen was detected in soil of natural forests of C. obtusa in Taiwan, in agreement with a possible Asiatic origin for this species.

[8] Recent outbreaks have been recorded on C. lawsoniana in France,[7] Scotland,[9] Northern Ireland, and the Netherlands.

[10] Since C. lawsoniana and T. brevifolia are both key components of ecosystems on the Pacific Northwest Region of North-America, P. lateralis is threatening the ecological and economical values of forests where the pathogen occurs.

Because of its potential economic impact, this pathogen was added in 2006 to the A1 list of exotic species that the EPPO recommends to regulate as quarantine organisms.