MENSURATION CHARACTERISTICS OF Pinus greggii Engelm. ex Parl. var. greggii FROM NINE PROVENANCES IN GALEANA, NUEVO LEÓN

Abstract

Provenance assays can include a broad interval of the natural distribution of species in order to identify the variation patterns of the best sources of seeds. The objective of this study was to compare the average values of height and diameter in Pinus greggii var. greggii trees of nine natural provenances of northern Mexico, established at Ejido 18 de Marzo, in the municipality of Galeana, Nuevo León. The experimental design consisted of randomized complete blocks to control the environmental component, particularly the conditions of the soil and the slope; the total height and diameter variables were measured at 4.5, 5.0 and 10.9 years after the trees were planted. Variance analyses showed significant statistical differences (P ≤ 0.01) in total height and diameter between the different provenances in all evaluation dates; the tallest specimens in the first evaluation were found in Agua Fría (1.37 m), surpassing those of all other sources in the subsequent evaluations as well, with 2.4 and 6.8, respectively. In contrast, the specimens from Puerto San Juan had the lowest heights: 1.0, 1.8 and 5.8, respectively. The diameters of the trees from La Tapona were somewhat larger than those of the Agua Fría specimens in the last evaluation. Furthermore, it was observed that the trees with the largest diameter came from the sites with the lowest values for altitude, longitude, and latitude.