Invasive alien species are widely recognised as significant drivers of global environmental change, with far
reaching ecological and socio-economic impacts. The trend of continuous increases in first records, with
no apparent sign of saturation, is consistent across all taxonomic groups. However, taxonomic biases exist
in the extent to which invasion processes have been studied. Invasive forest pathogens have caused, and
they continue to result in dramatic damage to natural forests and woody ecosystems, yet their impacts
are substantially underrepresented in the invasion science literature. Conversely, most studies of forest
pathogens have been undertaken in the absence of a connection to the frameworks developed and used to
study biological invasions. We believe this is, in part, a consequence of the mechanistic approach of the
discipline of forest pathology; one that has been inherited from the broader discipline of plant pathology.
Rather than investigating the origins of, and the processes driving the arrival of invasive microorganisms, the focus of pathologists is generally to investigate specific interactions between hosts and pathogens, with
an emphasis on controlling the resulting disease problems. In contrast, central to the field of invasion science,
which finds its roots in ecology, is the development and testing of general concepts and frameworks.
The lack of knowledge of microbial biodiversity and ecology, speciation and geographic origin present
challenges in understanding invasive forest pathogens under existing frameworks, and there is a need
to address this shortfall. Advances in molecular technologies such as gene and genome sequencing and
metagenomics studies have increased the “visibility” of microorganisms. We consider whether these technologies
are being adequately applied to address the gaps between forest pathology and invasion science.
We also interrogate the extent to which the two fields stand to gain by becoming more closely linked.
This paper emerged from a workshop on ‘Frameworks used in Invasion Science’ hosted by the DSI-NRF Centre of Excellence for Invasion Biology in Stellenbosch, South Africa, 11–13 November 2019.