A cautionary tale about urban trees: could ecoservice monetary estimates become economic sleights of hand?

Estimating the monetary value of ecosystem services bridges biophysical and economic systems, facilitating dialogue and decision-making among diverse stakeholders of nature. However, the more we translate natural phenomena into monetary units to unify diverse perspectives of nature's value, the more we risk losing. The search for a single underlying unit of existence (a monad) is a long-standing philosophical concept (monism) that has aided scientific progress. In the present article, we examine major monads in natural science en route to an exploration of the risks inherent to inadvertently adopting money as a monad (monetarianism). Through a cautionary tale and case study of an urban greenspace, we highlight the hazards of monetary representations of nature and present a new view of the potential for miscalculation. A monetary monism risks obscuring the true worth of biophysical processes behind an economic sleight of hand that could lead to the loss of ecosystem services and their monetary value.