Citizens map missing and damaged urban trees across hundreds of Spanish municipalities
Volunteers in more than 300 Spanish towns surveyed street tree pits, identifying thousands of empty, dead-tree or poorly sized sites under the “¡Aquí falta un árbol!” campaign.
A nationwide citizen-science initiative called “¡Aquí falta un árbol!” mobilised volunteers from over 300 Spanish municipalities to map the state of street tree pits. Roughly five hundred community organisations, ranging from neighbourhood associations to ecological and senior groups, coordinated participants through local coordinators and WhatsApp groups. Each volunteer walked a three-kilometre route, geolocating pits that were empty, contained dead stumps, or were classified as “asphyxiating” because they restrict root growth.
Using a custom mobile tool, the information was uploaded in real time to create an interactive “Ecomapa” on Ecomapa.org, detailing problem sites by street. Participants reported that the activity revealed a pervasive lack of adequate tree infrastructure, underscoring the need for planting new trees and improving soil conditions to enhance shade, air quality and urban biodiversity. The organizers plan to submit the findings to municipal authorities to guide future greening efforts.
Why it matters
The mapping exposes gaps in urban greenery, informing local actions to mitigate heat and improve residents' health.
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