Producing biomass energy requires much land, and effects of biomass production on ecosystem services could greatly affect total biomass energy cost. This study estimates switchgrass production cost in western Massachusetts at three levels: private production cost, private cost plus social cost of nitrogen fertilizer externalities, and those costs plus the social opportunity cost of foregone forest ecosystem services. Values for nitrogen externalities and forest ecosystem services estimated with benefit transfer suggest that social cost is much greater than private switchgrass production cost. The benefit-transfer estimates are only first approximations, but conclusions are robust to a large range of values.