Effect of Fertilization on Growth of Eucalyptus urophylla Plantation

Fertilization has been widely applied to increase and sustain productivity of plantations, especially in poor soils. N, P, K, and compost are usually used for forest plantation in Vietnam. The amount of fertilizer and rates of concerned nutrient are decided basing on species and edaphic condition. In this study, four fertilizer applications were used at planting; 100 g NPK+200 g compost, 150 g NPK+150 g compost, 200 g NPK+100 g compost, and control (no fertilization) for Eucalyptus urophylla plantation grown in North Central and Southern, Vietnam with planting density of 1,330 trees ha-1 (spacing 2.5 × 3 m). Growth data were collected after planting three years. Fertilizer applications had significant effects on diameter at breast height (DBH), crown diameter (Dc), and dry biomass of 3-year-old plantations in both sites. A 3-year-old. E. urophylla plantation had largest DBH (9.7 cm) and dry biomass (67.2 Mg ha-1) in fertilizer application of 200 g NPK+100 g compost in Southern site, and smallest DBH (6.4 cm) and dry biomass (38.2 Mg ha-1) in control also in Southern site. Comparing between two sites at three treatments with fertilizer indicated the significant higher dry biomass in Southern site than that in North Central site. While, it was converted in control, indicating higher dry biomass in North Central site. To grow E. urophylla, 200 g NPK+100 g compost should be applied at planting for Southern site. While, 100 g NPK+200 g compost is encouraged for North Central site.