ASSESSMENT OF A Pinus greggii Engelm. PLANTATION WITH TWO DIFFERENT SPACINGS

Abstract

Forest plantations established in the Sierra Purhépecha, Michoacan, currently increase slowly in height and diameter, as well as in survival rates, because they were established without a specific objective, with an inappropriate choice of species, incorrect densities in relation to the productive capacity of lands and lack of follow-up. The limited information on growth and development of plantations with exotic species motivated the present study, aimed to assess the development in diameter, height and survival of a Pinus greggii, set at two different spacings, of 2.0 x 4.0 m and of 2.50 x 4.0 m. The plantation was established on lands that belong to the Indigenous Community of Cheranastico, Paracho municipality, Michoacan State, in July 1999, in Andosol soil, with a slightly undulating topography, a slope of 5% and an altitude of 2,293 m. The plant was grown in containers with a capacity of 160 cells. For the preparation of the land, fallow was conducted at 30 cm depth. Experimental design was a randomized block with two treatments and six replications; the experimental unit consisted of 60 trees. Results at six years showed significant differences among treatments for the height and diameter variables, but not in survival. The densities tested to assess the variation in growth and behavior of P. greggii for agroforestry plantations, and based on the productive capacity of the soil, must use the spacing of 2.0 x 4.0 m, which achieved better growth in height and diameter.