Urban trees are a cornerstone of 21st-century cities, serving as the most immediate source of nature in our highly urbanised world. Their benefits are extensive; they improve public health, offer calming green spaces, and contribute to the socio-cultural fabric of city life. Ecologically, urban forests are vital in the fight against climate change, mitigating the urban heat island effect, reducing air pollution, and acting as powerful carbon sinks that can harbour more carbon per hectare than some tropical forests. These green assets also host diverse wildlife and provide essential recreational spaces for citizens. However, traditional tree mapping efforts are often costly, labour-intensive, and slow. Furthermore, manual surveys typically only capture trees in accessible areas like parks and roadsides, leading to a significant underestimation of the total urban canopy.

In this short demonstration, we showcase a reproducible framework to move from disparate geospatial datasets to a cohesive, building-level description of green infrastructure at a national scale. Our approach leverages several state-of-the-art tools to overcome the limitations of traditional methods. We aimed to quantify the 3-30-300 rule for urban greening—a “rule of thumb” policy stating that every citizen should see 3 trees from their home, live in a neighbourhood with 30% canopy cover, and be within 300 metres of a public park.