Research on Silvicultural Techniques of Native Tree Species in Central Area of Yunnan Province

An experiment was conducted with different site preparation measures,different fertilizer types and varied fertilization dosages applied to 12 native tree species in the central area of Yunnan Province,and the growth status of the experimented trees was measured and analyzed 5 years later after the afforestation.The results showed that the trench building was the best site preparation type,whereas the pit preparation was the most economic and applicable method.Nitrogen and potassium fertilizers could significantly promote the growth rate of the tested tree species,but the application of phosphorous fertilizer did not show obvious effect on growth promotion.The appropriate application dosage of ammonium nitrate was 50 ～ 100 g per plant,that of potassium sulfate was 30 g per plant,and 100 g of potassium sulfate per plant applied would restrain the growth of both basal diameter and crown diameter of the majority of tested tree species;central area of Yunnan Province.