Agreement levels of London tree officers towards the benefits and costs of urban forests

Abstract

Public perceptions of urban forests have been widely investigated, but the professional practitioners’ views have received little attention. Surveying the opinions of tree professionals could inform and fine-tune urban forest policies and practices. The opinions of 79 tree officers in London were evaluated. Our questionnaire assessed the levels of agreement with 66 statements stating the benefits and costs associated with urban trees and green space (referred to as urban forests). It allowed quantitative analysis of responses, accompanied by qualitative assessment of written comments. Respondents expressed high agreement with benefits related to environmental quality and human well-being. The regulating benefits were appreciated at a weaker level. The comments indicated keen awareness of underlying factors of benefit delivery, their conditional nature and practical limitations, and sound scientific evidence. Statements concerning costs received more divergent views with lower agreement scores. This result was attributed to the belief that planting design and management could minimise costs. Cluster analysis identified five officer clusters harbouring disparate latent mindsets, which could be subsumed under two aggregate groups based on the agreement ratio between benefits and costs. The mainstream view did not seek a lot more native than non-native trees. Awareness of the practical limitations of native species could have dampened the desire. Working experience and age influenced the agreement levels far more than other socio-demographic factors. The findings implied potential obstacles to urban forest management for regulating benefits due to officers’ preference for other functions and cost reduction.