While researchers recognize the health and ecological benefits of green infrastructure, at the level of city governance trees are relegated to second class status compared to other infrastructure with which they compete for space in the public right-of-way. The result is an unwelcoming environment for walking, cycling, and socializing, particularly in disadvantaged neighborhoods, at a time when city governments are also pursuing ambitious plans for Complete Streets and green infrastructure to address compound challenges related to health, equity, and the environment. This article contributes a thorough review of municipal street tree spacing guidelines through a comparison of guidelines in eight California and nine large U.S. cities, consideration of their change over time, an in-depth examination of laws applying to tree placement in Los Angeles, and interviews with City of Los Angeles staff. Results demonstrate that guidelines in many of the municipalities studied are more restrictive than legally required, vary greatly between cities even while evidence does not support the efficacy of one approach over another, and have not changed substantially over time to align with shifting priorities. Centralized control of the right-of-way could help align guidelines and practice with municipal goals and facilitate consideration of competing priorities.

中文翻译：

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将行道树提升到基础设施地位：洛杉矶与美国同行城市的行道树间距指南比较


虽然研究人员认识到绿色基础设施对健康和生态的好处，但在城市治理层面，与其他基础设施争夺公共通行权空间相比，树木被降级为二等地位。结果是步行、骑自行车和社交的环境不受欢迎，尤其是在弱势社区，而市政府也在追求雄心勃勃的完整街道和绿色基础设施计划，以应对与健康、公平和环境相关的复杂挑战。本文通过比较 8 个加利福尼亚州和 9 个美国大城市的指导方针，考虑它们随时间的变化，深入审查适用于洛杉矶树木放置的法律，以及对洛杉矶市工作人员的采访，对市政街道树木间距指南进行了全面审查。结果表明，所研究的许多城市的指导方针比法律要求的限制性更强，即使证据不支持一种方法优于另一种方法的有效性，城市之间的指导方针也有很大差异，并且随着时间的推移没有发生重大变化以与不断变化的优先事项保持一致。对通行权的集中控制有助于使指导方针和实践与市政目标保持一致，并促进对相互竞争的优先事项的考虑。