Abstract

The aim of the study was to evaluate the effect of nitrogen, phosphorus and potassium fertilization on the initial development of Tachigali vulgaris plantations for the production of forest biomass. The experiment was set up in the municipality of Igarapé-açu, Pará, Brazil and evaluated over one year. The planting was carried out with 1728 plants at a spacing of 2 m x 3 m and used a completely randomized design with seven fertilization treatments. Measurements included plant height and diameter, as well as leaf nutrient analysis. The results indicated significant growth responses to N, P and K, particularly in height, with plants that received 44.5 kg.ha-1 of N showing the greatest increase (534 cm). Potassium also significantly influenced growth, with a notable average increase in height of 77 cm compared to plants without fertilization. Leaf nutrient analysis revealed better nutrient assimilation correlated with fertilizer applications. The study concluded that the combined fertilization of 44.5 kg.ha-1 of nitrogen and 50 kg.ha-1 of potassium improves the morphological development of T. vulgaris, representing an effective strategy for optimizing growth and productivity in forest plantations. These results demonstrate the importance of balanced fertilization for sustainable biomass production using the T. vulgaris species.