METHODS FOR MASS PRODUCTION OF IMPROVED STOCKS BY ROOT CUTTINGS OF CHINESE FIR Quantitative Analysis on the Economic Characters of Castanea henryi Nut Leading Shoot Elongation Rhythm and Its Potential Role in Selection of Eucalypt Clones The High Seed Yield Tests in Slash Pine (Pinus elliottii Engel.) Orchard in Changle Forest Farm Genetic Variation and Initial Selection of Clones from Hybrid between Populus deltoides Marsh.×P.cathayana Rehd.