Treena Burgess

A successful citizen science project requires three primary components. First, a compelling research topic focused on an issue comprehensible by the broader community; second, an engagement strategy that communicates the issues and creates partnerships with scientists and the community; and third, efficient, flexible technology to implement the program. Information is a key output of a successful citizen science project. Not only must the data be of high quality when captured but they must be easily accessible subsequently to both contributors and scientists. For community members this completes a feedback loop, allowing them to see the results of their efforts in a broader context. For scientists, the data must be available in a form fit for further analysis. In this article we present the Marri Canker Project as a case study that: • Addresses a specific environmental issue of interest to both researchers and the broader community. • Engages with passionate community members who advise, learn and contribute data from the field. • Utilises a smartphone app to aid identification and facilitate data capture in the field, improving both the quantity and quality of data being contributed to the project.

A severe canker disease has been contributing to decline in marri (Corymbia calophylla) for some years now. Cankers are a symptom caused by the death of areas of bark and the cortex tissue below that, and are caused by the plant pathogen Quambalaria coyrecup. The canker is present on trunks, branches and twigs of trees of all ages. Canker disease occurs on marri across the natural range of this tree in south west WA. It also affects amenity-planted red flowering gum (C. ficifolia). Once canker symptoms are evident, trees do not appear to be able to recover, and given the large number of infected trees, the future health of marri in south west WA is of serious concern.