**4. Conclusions: Vegetation as an Element of Urban Morphology**

In the medieval morphology of Alfama, trees are scarce and appear in sporadic positionings. Most of these trees, individually, constitute landmarks. In some situations, groups of trees form protecting domes constituting semi-enclosed spaces and generally, throughout the homogeneous area, gatherings of vegetation in different types of pots adjoining the public space form part of the collective landscape. In the post-industrial Avenidas designed by Ressano Garcia, tree alignments are the dominant vegetation form, emphasizing the proposed rectilinear tracings. In some situations, the volume resulting from these alignments competes with the height of adjacent buildings. Finally, in the modern Alvalade neighbourhood, vegetation is highly present. It encompasses the combination of vegetation alignments with occasional volumes of dense and irregular vegetation. In some situations, regular tree and shrub alignments serve staging purposes. In other situations, trees and shrubs rather serve as borders that confine and consolidate privileged spaces.

In this study, the main characteristics of the urban structure are revealed, together with the importance of vegetation as an element of urban morphology (Figure 15), which significantly contributes to the understanding and interpretation of the city. If other homogeneous areas were analysed, new urban morphological components would very likely be identified.

**Figure 15.** Systematization of the tree aggregation forms in accordance with the analyzed urban structures.

Most importantly, this initial systematization process serves to improve knowledge on the reading of urban greenery, also offering another set of values for contemporary design processes. Indeed, the use of morphological analysis as an analytical methodology is both an exploratory tool to understand existing urban, architectural and vegetation forms, and a tool for the creation of new forms. In this sense, the urban morphology exercise gains relevance in architectural and landscape architectural education, providing tools to improve the process of creative research and design. Overall, these outputs, methodology and theoretical framework aim to contribute support to a design process that can respond to the challenges of the contemporary city and improve human well-being through the acknowledgement of vegetation as a contributor to the creation of specific, unique and unrepeatable spaces within urban landscapes.

**Author Contributions:** R.J., M.M.S. declare that each have contributed equally to the production of this document. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was supported by Fundação para a Ciência e a Tecnologia through a PhD fellowship in Urbanism (SFRH/BD/116371/2016).

**Acknowledgments:** The authors would like to thank Formaurbis Lab, a research group on urban morphology from the Lisbon School of Architecture—Universidade de Lisbon and especially Sérgio Proença, a team member, for allowing full access to the data of Lisbon: a set of elements used as a basis for the production of the manuscript drawings and some photographs.

**Conflicts of Interest:** The authors declare no conflict of interest.
