Significant improvements to the technique of minicutting Eucalyptus clones have been reported in the literature. However, despite these recent efforts, studies addressing the proper size of minicuttings and the reduction of leaf area have not been well explored. Thus, the present study had the objective of evaluating the effects of the length of the minicuttings and the leaf area reduction on the growth and nutritional condition of Eucalyptus urophylla during propagation. The experiment was conducted for 90 days in the Plantar Reforestation Co. Nursery in the municipality of Curvelo, MG, using a randomized block design with 4 replicates in a factorial arrangement. The effects of 4 lengths of minicuttings (4, 6, 8, and 10？cm), 2 levels of leaf area reductions (0 and 50%), and 2 commercial clones were studied. The length of the minicuttings and the reduction of leaf area did not affect the nutritional status of the leaves, nor did the length affect the quality of the plants at the age of 90 days. The results indicate that it is unnecessary to reduce the leaf area for Eucalyptus propagation. 1. Introduction The propagation of plants by minicuttings is a widely used technique employed for the production of Eucalyptus seedlings and has been published in various media. The scientific literature has shown that much of the success of this technique depends on the selection of the appropriate propagules and proper silvicultural practices, which aim to ensure efficiency in the production of high-quality seedlings [1]. In the production process, nurseries customarily produce clonal Eucalyptus plants with minicuttings ranging in size from 4 to 10 cm, with at least two pairs of leaves of reduced leaf area [2, 3]. The basic procedure for the reduction of leaf area on minicuttings used in most nurseries today is virtually the same as was used in plant propagation by cuttings (macrocuttings) in the 1980s and 1990s, although the vegetative propagules of minicuttings are smaller and more juvenile compared with macrocuttings. In addition, irrigation systems in nurseries have evolved significantly in recent years [4]. The retention of leaves or parts of leaves on the stem is necessary for the production of auxins and rooting cofactors that are translocated to the cutting base and promote rooting [5, 6]. Lima et al. [7] evaluated the effect of a reduction in leaf cuttings of Mikania spp. (Guaco) and found that an increase in leaf area positively influenced the percentage of rooting and the survival of the plants. Reuveni and Raviv [8] observed a higher percentage of rooting
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