This study analyzes the planting decisions made by urban greenery managers in Warsaw between 2012–2017. The results showed that the species composition of planted trees was suboptimal. The tree species with higher dieback were planted more often than the tree species with relatively lower dieback. Moreover, the conducted econometrical analysis revealed that this important characteristic was not statistically significant for the planting decisions made by the urban greenery managers. A closer look at the functioning of the urban greenery management system in Warsaw revealed that this situation could potentially result from the phenomenon described in the agency theory as a principal-agent problem. Dieback was a feature difficult to include in the decision-making process in Warsaw without conducting nonobligatory and effort-intensive in situ studies. Meanwhile, the contract between the greenery managers (agent) and the city authorities (principal) was not “incentive-compatible”. It favored less effort-intensive decision-making, i.e. making planting decisions by greenery managers based on their intuition and experience, rather than on effort-intensive in situ analyses. The study suggests that the principal-agent problem should be further investigated as a potential barrier to optimal management of urban greenery.

本研究分析了2012-2017年间华沙城市绿化经理做出的种植决策。结果表明，人工林的树种组成次优。具有较高的枯萎率的树种比具有相对较低的枯萎率的树种种植得更多。此外，进行的计量经济学分析表明，这一重要特征对于城市绿化管理者做出的种植决策没有统计学意义。仔细研究华沙的城市绿化管理系统的功能，可以发现这种情况可能是由代理理论中描述为委托代理问题的现象造成的。如果不进行强制性和费力的工作，Dieback是难以包含在华沙决策过程中的功能原位研究。同时，绿化管理者（代理人）和市政府（主要人）之间的合同不是“激励兼容的”。它倾向于减少工作量大的决策，即由绿化经理根据他们的直觉和经验做出种植决策，而不是根据工作量大的原位分析做出种植决策。研究表明，应进一步调查委托代理问题，将其作为城市绿化最佳管理的潜在障碍。