Background:Forests contribute to human wellbeing through the provision of important ecosystem services.Methods:In this study,we investigated how the perceived importance of ecosystem services may impact the overall benefit provided by managed watersheds at the Hubbard Brook Experimental Forest over a 45-year period,using standardized measures of service capacity weighted by service importance weights derived from a survey of beneficiaries.Results:The capacity of watersheds to regulate water flow and quality was high in all watersheds throughout the study period,whereas cultural services such as scenic beauty declined after harvest.Impacts on greenhouse gas regulation depended on the efficiency with which harvested biomass was used.Surveys revealed that stakeholders placed high value on all ecosystem services,with regulating and cultural services seen as more important than provisioning services.When service metrics were weighted by survey responses and aggregated into a single measure,total service provision followed the same overall trend as greenhouse gas regulation.Where biomass use was less efficient in terms of greenhouse gas emissions,harvesting resulted in an overall “ecosystem service debt”;where use was more efficient,this “ecosystem service debt” was reduced.Beneficiaries’ educational backgrounds significantly affected overall assessment of service provision.Beneficiaries with college or university degrees incurred smaller “ecosystem service debts” and were less negatively affected by harvesting overall.Conclusions:This study highlights the importance of including empirical measures of beneficiary preference when attempting to quantify overall provision of ecosystem services to human beneficiaries over time. Background: Forests contribute to human wellbeing through the provision of important ecosystem services. Methods: In this study, we investigate how the perceived importance of ecosystem services may impact the overall benefit provided by managed watersheds at the Hubbard Brook Experimental Forest over a 45-year period, using standardized measures of service capacity weighted by service importance weights derived from a survey of beneficiaries. Results: The capacity of watersheds to regulate water flow and quality was high in all watersheds the the study period, but cultural services such as scenic beauty declined after harvest.Impacts on greenhouse gas regulation depended on the efficiency with which harvested biomass was used. Surveys revealed that stakeholders placed high value on all ecosystem services, with regulating and cultural services seen as more important than provisioning services. survey responses and aggregated into a single measure, total service provision followed the same overall trend as greenhouse gas regulation. Where biomass use was less efficient in terms of greenhouse gas emissions, harvesting resulted in an overall “ecosystem service debt”; where use was more efficient, this “ecosystem service debt ”was reduced.Beneficiaries’ educational blocks significantly affected overall assessment of service provision.Beneficiaries with college or university degrees incurred smaller “ ecosystem service debts ”and were less negatively affected by harvesting overall. Conclusions: This study highlights the importance of including empirical measures of beneficiary preference when attempting to quantify overall provision of ecosystem services to human beneficiaries over time.