Impacts of Different Intermediate Cutting on Crown Structure of Manglietia yuyuanensis in Mixed Stands with Cunninghamia lanceolata Study on the Benefits of Intermediate Cutting of Chinese Fir Agglomerate Afforestation The Natural Thinning and Structural Pattern of the Intermediate Cutting Intensity in the Cunninghamia lanceolata Stand Growth Effect of Intermediate Cuttings Intensity Experiment for Twenty Years in Cunninghamia lanceolata Tentative study on Effects of Intermediate Cutting in Slash Pine Plantation Studies on the Timber Assortment Outturn and Economic Benefit of the Intermediate Cutting Intensity for Cunninghamia lanceolata Stands