This paper develops a dynamic, regional analysis of the effects of US and European biofuel mandates on land use, forestry stocks, and carbon emissions. The results suggest that these mandates may cause an additional 23-26 million hectares of forestland losses globally, but additional carbon emissions of 1.2 - 1.6 billion t CO2. The estimates are found to be sensitive to the elasticity parameter on the land supply function in the model, with the higher elasticity estimates associated with larger carbon losses. The regional analysis turns out to be quite important, because some regions end up gaining forestland and increasing carbon stocks. The regional and dynamic effects have been missed by most other noteworthy analyses of the induced land use effects of biofuel policies, potentially leading the authors to overstate the impacts by 3-6 times.