Basalt rock dust is a residue of basaltic rock mining with potential to be reused as a component of forestry substrates because of its important mineral elements, such as the macronutrients. This study aimed to evaluate the effects of residual basalt dust, mixed in different strengths with vermiculite and organic compound made from peat, in seedlings of Eucalyptus grandis W. Hill ex Maiden, 180 days after sowing. After analysis of the morphological indicators of quality forest seedlings, such as aerial part height (h), stem diameter (d), and aerial part height/stem diameter ratio (h/d), it was possible to conclude that basalt dust, in doses of 10 to 20% added to the substrates with mixtures of vermiculite and peat compost, is a component with favorable potential to the development of aerial part height and stem diameter in Eucalyptus grandis seedlings. It was also possible to observe that both the emergence of the aerial part and the seedling survival reached 100%.
residue; basaltic rock; nutrients