Resolving intractable soil constraints in urban forestry through research–practice synergy

In compact urban areas, grey infrastructure tends to prevail over green infrastructure. The tight urban fabric challenges tree growth and restricts development of greener and healthier cities. The admirable forest-city goal demands innovative methods and solutions tailor-made to tackle inherent constraints. Research findings could be more proactively transformed and transferred into practices. The aerial tree growth space, relatively less difficult to ameliorate, attracts more attention. The more intractable subterranean constraints of confined soil volume acutely restrict root growth, root spread and tree health and contribute extensively to premature decline and tree hazard. Soil surface sealing by impermeable paving is associated with compaction, organic matter deficit, low nutrient and water holding capacity and meagre nutrient stock. Scanty application of research findings has kept practice quality at a low level, rendering the persistent soil problems in the bane of urban forestry. A systematic survey of state of play provides hints on novel solutions derived from existing knowledge and proposes new research practice. A package of measures with generic connotations has been distilled from the survey of chronic, critical yet widely neglected urban soil management issues. Urban forest managers and researchers can jointly adopt out-of-the-box thinking and generate actionable translational research. Policy makers and practitioners can more promptly be informed by new harvests of research–practice synergy. Intimate and reciprocal interactions between science and practice can be proactively nurtured to raise the quality of urban landscape. Copyright © 2019 Springer Nature Singapore Pte Ltd.