The National Forest Inventory, created in 1958, merged in 2012 with the National Geographic Institute to create the National Institut for Geographic and Forestry Information, institution entrusted by Decree No. 2011-1371 of 27 October 2011 to update the permanent inventory of national forest resources provided for in Article L.151-1 of the forest code ( area, volume, organic production, harvesting, operability , phytoecological , etc.). The forest inventory method has evolved. Until 2004, it was made department by department, at intervals of 10 to 15 years. From 2005, a systematic sampling method applied throughout the national territory replaces departmental inventories. The accumulated data of successive annual enables IGN to publish results ever more accurate.
Source : service de la statistique et de la prospective (SSP), ministère chargé de l'agriculture (site : http://agreste.agriculture.gouv.fr)