ABSTRACT This work was carried out in a teak plantation in the state of Mato Grosso, Brazil. The objective was to evaluate technical and economic indicators of the cutting and processing of trees with a track harvester. Twenty complete work shifts were evaluated using direct thinning to determine operational cycle times. Other information was also recorded for the calculation of production costs. The second thinning was performed at 12 years, with a volume of 0.1648 m³/tree, and the third thinning at 18 years with 0.3408 m³/tree. The main finding was an increase in productivity and decrease in production costs with rising tree volumes. For each hour of effective work, 53 trees were cut (339 trees/day), and processed into 1,047 logs. The decrease in the cost of cutting and processing trees in proportion to the increase in the average volume of trees to be extracted was confirmed.

RESUMO: A produção de madeira de Tectona grandis (teca) em sistemas integrados com pecuária ou agricultura demonstra alta perspectiva de retorno financeiro. Entretanto, estudos sobre o desenvolvimento da teca ainda são escassos, principalmente na região norte de Mato Grosso. O objetivo do trabalho foi avaliar o crescimento das variáveis dendrométricos de um povoamento clonal de teca, em um sistema silvipastoril (iPF), ao longo de 53 meses, no município de Alta Floresta-MT, Brasil. Para isso, foram amostradas três parcelas, totalizando 360 indivíduos, sendo que em cada indivíduo foi mensurado o diâmetro a 1,3 m do solo e altura total. Em seguida realizou-se o cálculo do volume. Para descrever o crescimento da variável diâmetro, altura total e volume foi realizado o ajuste através de cinco modelos matemáticos que expressam o crescimento ao longo do tempo. Posteriormente, foram calculados o incremento corrente anual (ICA) e incremento médio anual (IMA). O modelo de Hoerl apresentou melhores resultados de R²aj, obteve menores valores para o erro padrão de estimativa (Syx) e para o CV%, com isso, foi selecionado para a elaboração das curvas de crescimento. O povoamento clonal de teca no iPF apresentou incremento em DAP, Altura e volume foram superiores em relação a outros estudos científicos com teca, indicando sua viabilidade em sistemas integrados com pastagens na região.

ABSTRACT: Production of Tectona grandis (teak) in integrated systems with livestock or agriculture demonstrates high potential of financial return. However, studies on the development of teak are still scarce, especially in the northern region state of Mato Grosso. In this study we sought to evaluate dendometric variables of a clonal population of teak in a forest-livestock integration system (LFIS), during a period of 53 months in the city of Alta Floresta, Mato Grosso, Brazil. For this purpose, three installments were samples, a total of 360 individuals, and for each the diameter was measured at 1.3 meters from the base so as to calculate the total volume, the current annual increment (CAI) and mean annual increment (MAI), and five adjusted regression models. The Hoerl model provided the highest adjusted coefficient of determination (R2aj), lowest standard error of estimate (Syx), coefficient of variation (CV %), and from this the growth curves were developed. Clonal stands of teakin the forest-livestock system presented increases in DBH, height and volume were superior in relation to other scientific studies with teak, indicating their viability in integrated systems with pastures in the region.

ABSTRACT The objective was to obtain a statistical model to estimate the operational performance of cutting trees with a chainsaw in the natural tropical forest north of Mato Grosso state. One-hundred-and-fifty-one operational cycles of selective logging for commercial purposes were registered. In each cycle, the effective time for cutting, the diameter of the trees, commercial height, the number of logs per tree, and the distance between trees was determined. A step-by-step regression analysis was performed to obtain the coefficients of the models and statistical parameters. The result of the analysis concluded that the most accurate model to estimate the operational performance is the one that transforms the diameter variable at breast height (DBH) squared and also includes the variables number of logs per tree and distance between logged trees.