Background:Thequantitativeimpactofforestmanagementonforests'woodresourcewasevaluatedforPiceaandFagusmixedforests.Theeffectsontheproductivityoftenderingoperations,thinningsandrotationlengthhaveseldombeendirectlyquantifiedonlandscapescale.Methods:Twositesofsimilarfertilitybutsubjecttocontrastedforestmanagementwerestudiedwithdetailedinventories:oneinGermany,theotherinRomania,andcomparedwiththerespectivenationalforestinventories.InRomania,regulationsimposeverylongrotations,lowthinningsandaperiodofno-cutbeforeharvest.Incontrast,tendingandthinningsarefrequentandintenseinGermany.Harvestsstartmuchearlierandmustavoidclearcuttingbutmaintainapermanentforestcoverwithnaturalregeneration.WhileGermanyhasanaverageannualwoodincrementrepresentativeforCentralEurope,RomaniarepresentstheaverageforEasternEurope.Results:ThelackoftendingandthinningintheRomaniansiteresultedintwiceasmanytreesperhectareasintheGermansiteforthesameage.TheproductivityinRomanianproductionforestswas20%lowerthaninGermanydespiteasimilarfertility.Theresultsweresupportedbythedatafromthenationalforestinventoryofeachcountry,whichconfirmedthatthesamedifferentialexistsatcountryscale.Furthermore,providedthedifferenceinrotationlength,twocropsareharvestedinGermanywhenonlyoneisharvestedinRomania.ThelossesofproductionduetoalowerlevelofmanagementinRomaniawhereestimatedtoreach12.8millionm~3·y~(-1)inregularmountainproductionforests,andto15millionm~3·y~(-1)ifmanagedprotectionforestisincluded.Conclusions:TheproductivityofPiceaandFagusmountainforestsinRomaniaisseverelydepressedbythelackoftendingandthinning,byoverlylongrotationsandtheexistenceofa25-yearsno-cutperiodpriortoharvest.TheaveragestandingvolumeinGermanywas50%lowerthaninRomania,butthehigherharvestingrateresultedinmorethandoublingwoodproduct
