It is asking members of the public to monitor trees' long-term health by tagging both diseased and healthy individuals with a unique ID number, then submitting images over a period of years.
The project uses an updated version of AshTag, a mobile phone app which which the team launched last year. It has since been downloaded around 12,000 times, with more than 1,000 suspected dieback sightings being reported.
The results are being fed back to researchers including those at the John Innes Centre working on the Nornex project, a network of research groups which aims to provide tools that can help understand and ultimately limit the impact of ash dieback.
UEA programme manager Chris Blincoe said: "We hope that thousands of people, from school groups and nature lovers to dog walkers and farmers will use the app to monitor the health of their local trees and become stewards for the nation’s ash population.
"We can then begin to understand how the disease progresses through trees at different stages of maturity, and importantly investigate why some trees remain uninfected for no clear reason."
Under the new phase, which is funded by the Esmee Fairbairn Foundation, participants are sent AshTag packs include five aluminium tree ID tags.