Municipal leaders worldwide are showing substantial interest in urban greening. This encompasses incentives, policies, and programs to vegetate urban landscapes, and it often includes urban tree planting initiatives (TPIs). Over the past decade there has been a seven-fold increase in scholarly use of terms denoting TPIs, and roughly two-thirds of associated studies address TPIs in the United States (U.S.). This reflects a bloom of scholarly interest in TPIs. Yet, there has been limited research on contemporary TPIs as historically situated cultural phenomena, and there has to the best of our knowledge been no nationwide survey of TPIs across municipal scales. Addressing these gaps, this article presents findings from a survey of 41 TPIs in the United States. We report on typical traits of U.S. TPIs across six themes: background, dates and goals, public awareness, funding and governance, planting, and stewardship. Respondents identified over 115 traits that distinguish TPIs from typical urban tree planting activity, suggesting that TPIs are a discrete form of urban forestry. Over two-thirds of TPIs are funded separate from traditional urban forestry, and lack of institutionalization raises questions about long-term viability. TPIs mobilize political and financial resources for program launch, tree purchasing, and planting, but there may be a need for greater investment in stewardship activities and the social infrastructure that undergirds green infrastructure. Large shade trees for ecosystem services and native trees are the principal factors informing TPI species lists. Beautification and regulating ecosystem functions are, in turn, the principal potential benefits animating tree planting goals, yet few TPIs have conducted research to assess the fulfillment of associated outcomes. This study provides a foundation for future interdisciplinary scholarship on TPIs across the humanities, natural sciences, and social sciences.

世界各地的市政领导人对城市绿化表现出极大的兴趣。这包括用于植被城市景观的激励措施，政策和计划，并且通常包括城市植树计划（TPI）。在过去的十年中，表示TPI的术语在学术上的使用增加了7倍，大约有三分之二的相关研究都针对美国（TP）。这反映出对TPI的学术兴趣激增。但是，关于当代TPI作为历史悠久的文化现象的研究很少，据我们所知，还没有全国范围内对TPI进行全国范围的调查。针对这些差距，本文介绍了对美国41个TPI的调查结果。我们报告了六个主题下的美国TPI的典型特征：背景，日期和目标，公众意识，资金和治理，种植和管理。受访者确定了超过115个将TPI与典型的城市植树活动区分开的特征，这表明TPI是城市林业的一种离散形式。TPI的三分之二以上是与传统的城市林业分开资助的，缺乏制度化引发了人们对长期生存能力的质疑。TPI调集政治和财政资源用于计划启动，树木购买和种植，但是可能需要在管理活动和支持绿色基础设施的社会基础设施上进行更多的投资。用于生态系统服务的大型遮荫树和本地树是告知TPI物种清单的主要因素。美化和调节生态系统功能反过来是 植树造林的主要潜在效益，但很少有TPI进行过研究来评估相关成果的实现情况。该研究为未来跨人文，自然科学和社会科学的TPI跨学科学术研究提供了基础。