Urban residents and government arborists’ preferences and rationales for tree species in West African cities

Abstract

Urban tree species preferences and selection criteria that influence urban greening strategies vary across socio-ecological contexts. This paper reports on species preferences among urban residents and government arborists in ten west African cities, the reasons behind these preferences, as well as disliked species. Using surveys, we analysed species preferences, motivations for favouring or disliking a particular species, and the degree of alignment between resident preferences and arborist planting decisions. Across the ten cities studied in Benin Republic, Ghana, and Nigeria, residents identified 70 tree species as their favourites, with respondents in each city mentioning between 16 and 28 species. Species diversity was reflected in the Shannon-Wiener index, which ranged from 2.04 to 3.05, indicating substantial biodiversity within urban environments. However, only four species, Mangifera indica L. (mango), Citrus aurantium f. aurantium (sweet orange), Carica papaya L. (papaya), and Elaeis guineensis Jacq. (oil palm), were consistently mentioned in all cities. Residents prioritise species for fruit and shade, while arborists prioritise for carbon sequestration and aesthetics. Despite some overlap in species selection, significant disparities existed between urban dwellers’ preferences and arborists’ decisions, highlighting the need for better co-designing and co-managing approaches that are often overlooked in top-down greening initiatives. Our research suggests that future tree-planting projects in the region should consider incorporating trees that have been highlighted as preferred species by residents to ensure that both ecological and social needs are addressed.