Trees in urban environments play a crucial ecological role, helping to mitigate air pollution, reduce urban heat islands, improve stormwater drainage, and provide essential ecosystem services such as biodiversity conservation. Street trees, in particular, form an interconnected network within the urban fabric, offering the potential to link various green spaces across the city. Several cities have implemented dedicated Street Tree Master Plans (STMPs) to manage street trees effectively. A STMP thus serves as both a vital tool for the management and conservation of urban tree heritage and an opportunity to enhance public spaces and the quality of life for citizens. This case study of Rome (Italy) presents a particularly complex challenge, partly due to the city’s rich historical heritage, where street trees contribute to the identity of places and the urban environment in the context of climate change. The tree heritage of Rome requires ongoing maintenance, the improvement of growing conditions, the replacement of hazardous or aging trees along street rows, and the addition of new trees to enhance and diversify the urban tree population. Starting from a new census of street trees and a spatial analysis using GIS methodologies, this study examines the approach taken by Rome’s STMP. It focuses on the different strategies proposed for various types of streets, classified on the specific role that trees play in each context. Specifically, the plan offers a strategic vision for the city’s future, rooted in its urban form and supported by a methodological framework for planning interventions based on the current condition of tree cover. Drawing on insights from the STMP, the findings emphasize that any comprehensive renewal of street trees in large cities with historically significant and aesthetically rich landscapes must be guided by a strategic vision. In the discussion, a comparative analysis was conducted on different STMPs in various cities around the world, and we questioned how significantly historical and spatial considerations, which characterized the formation of Rome’s STMP, should be part of all STMPs.

Street trees play a fundamental role in shaping pedestrian sidewalks, squares, and small rest areas, enriching the public space, together with paving, street furniture, and lighting. However, the project of street tree lines along urban sidewalks remains an underestimated issue in urban design and strategic planning, even if it could be a pivotal opportunity for a widespread redevelopment of living streets and public spaces. The present study focuses on landscape aspects of the ‘street tree project’ intrinsically linked with the identity, perception, and morphological issues of urban spaces, from a strategic vision of the city to the human scale of the urban landscape. In this perspective, we discussed the case of Rome, Italy, where the historical heritage has had an extraordinary value, and where street trees are considered a notable contribution to the landscape identity of the whole city. The administrative council of the Municipality of Rome has initiated a comprehensive census of street trees and is currently developing a Street Tree Masterplan. This plan will serve as a guiding framework, outlining strategies for the conservation of arboreal heritage and the revitalization of the urban tree population along city streets. Based on the empirical evidence stemming from this case study, the discussion highlights the relevance of poorly debated issues, in both the academic and practitioner’s literature, mainly concerning the choice of urban trees’ species. Choosing the ‘right tree species in the right place’ has implications that are not only ecological and environmental, but also perceptive and architectural, being intimately associated with the urban scene and the identity of places.

Climate warming, agricultural intensity, and urban growth are main forces triggering land degradation in advanced economies. Being active over different spatial and temporal scales, they usually reflect—at least indirectly—the impact of additional factors, such as wellbeing, demographic dynamics, and social development, on land quality. Using descriptive statistics and a multiple regression analysis, we analyzed the impact of these three processes comparatively over a decadal scale from 1960 to 2020 at the provincial level (Nuts-3 sensu Eurostat) in Italy. We enriched the investigation with a short-term forecast for 2030, based on four simplified assumptions grounded on a purely deterministic approach. Land degradation was estimated adopting the Environmental Sensitive Area Index (ESAI) measured at the spatio-temporal scale mentioned above. Computing on multiple observations at nearly 300,000 locations all over Italy, provinces were regarded as representative spatial units of the territorial pattern of land degradation. Between 1960 and 1990, the three predictors (climate, agriculture, and urbanization) explained a relatively high proportion of variance, suggesting a modest role for any other (unobserved) factor. All of these factors were found to be highly significant predictors of land degradation intensity across provinces, the most impactful being farming intensity. The highest adjusted-R² coefficient was observed in both 1990 and 2000, and suggests that the three predictors still reflect the most powerful drivers of land degradation in Italy at those times, with a marginal role for additional (unobserved) factors. The impact of farming intensity remained high, with the role of urbanization increasing moderately, and the role of climate aridity declining weakly between 2000 and 2010. In more recent times (2010 and 2020), and in future (2030) scenarios, the adjusted R² diminished moderately, suggesting a non-negligible importance of external (unobserved) factors and the rising role of spatial heterogeneity. The climate factor became progressively insignificant over time, while increasing the role of urbanization systematically. The impact of farming intensity remained high and significant. These results underlie a latent shift in the spatial distribution of the level of land vulnerability in Italy toward a spatially polarized model, influenced primarily by human pressure and socioeconomic drivers and less intensively shaped by biophysical factors. Climate aridity was revealed to be more effective in the explanation of land degradation patterns in the 1960s rather than in recent observation times.

Systematic, spatially explicit tree inventories are increasingly implemented in cities worldwide, as they are crucial for evidence-based green infrastructure planning. Currently, different approaches are adopted, which differ in methodological framework and parameter standardization, limiting comparative assessments and coordinated monitoring. This study presents a replicable protocol for a field-based digital street tree census, applied in a densely built central area and in a low-density suburban area of Rome. Field surveys documented a set of 15 parameters, including species identity, dendrometric and tree pit parameters, acquired using open-source QGIS/QField tools. Subsequent analysis evaluated floristic diversity, population structure, and climate suitability at the neighborhood scale, enabling the identification of context-specific vulnerabilities. The testing of the methodology shown in this work involved 13,017 georeferenced tree pits, pointing out substantial pit restoration needs and insufficient soil conditions in the most densely urbanized area, whereas the suburban area shows optimal conditions with extensive road verge green spaces. Joint interpretation of the considered parameters reveals that high floristic diversity alone does not guarantee climate resilience: high-diversity neighborhoods can exhibit substantial non-climate-resilient species and limited alignment with local species recommendations, demonstrating that comprehensive evaluation of street tree populations requires integrated analysis. The operationalized protocol establishes a replicable, municipally scalable methodological framework, providing policymakers with fine-scale, actionable insights enabling differentiated urban forestry strategies addressing both infrastructure deficits and long-term species climate suitability.