Fig. 2
From: Sustainable forest biomass: a review of current residue harvesting guidelines
Number of new or revised forest biomass harvesting guidelines released by year in European and North American jurisdictions and regions (from Additional file 1: Table ST-1 and from the literature). Jurisdictions with revised guidelines include Finland (2006, 2010, 2014, 2016 work guide), Massachusetts (2012, 2013 2nd edition), Michigan (2010, 2012 stand retention at harvesting), Minnesota (2007, 2013), Norway (1998, 2008, 2016 PEFC standard), Sweden (1986, 2001, 2008), the UK (1997, 2009) and Wisconsin (2009, 2014)