This study aimed to test different doses and sources of fertilizers to verify the growth of seedlings of five native tree species. The species used were the pioneers Guazuma ulmifolia (mutambo) and Croton floribundus (capixingui), the early secondaries Peltophorum dubium (canafístula) and Gallesia integrifolia (pau-d'alho) and the climax Myroxylon peruiferum (cabreúva). The treatments consisted mainly of the use of controlled-release fertilizers (CRF, 19-06-10, N-P2O5-K2O) alone or combined with powder fertilizers (PF, 14-16-18) or with PF and periodic covering fertilization (PCF, 19-06-20) compared with conventional fertilization (base fertilization plus covering fertilization with ammnonium sulfate and potassium chloride) and control (without fertilization). The substrate was composed of 60% earthworm humus + 30% carbonized rice husk and 10% subsoil, by volume. Tubes of 50 cm3 capacity were used as containers. Among the treatments that produced seedlings of good quality at the end of the experiment for each species, the treatments with doses of 3,2 and 4,8 kg of controlled-release fertilizers by m3 of substrate were common to all species, also resulting in appropriate dimensions for field planting at a shorter time than the other treatments.
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