Structural attributes of Pinus montezumae Lamb. in reforestation areas in the state of Puebla

Introduction Reforestation’s efficiency as an strategy in ecological restoration can be effectively evaluated by examining ecosystem structure, species composition, and underlying ecological functions. Objective To determine the horizontal and vertical structure in two areas reforested with Pinus montezumae Lamb. and in a reference forest. Materials and methods The study was conducted in two P. montezumae reforestation sites (five and nine years old) and one reference forest. In circular plots of 400 m2 in each zone, the following tree variables were measured: diameter at breast height (DBH) and tree height. These measurements were used to calculate basal area, volume, and tree density. The importance value index (IVI) was also estimated. Results The reforested areas are in an early stage of development, between shrubland and young forest. The reference forest showed the largest average tree diameter (39.8 cm) and height (18.1 m), indicating a mature forest structure. Basal area, volume, and tree density were significantly different (p ≤ 0.05) among the three sites. In the reference forest, Pinus teocote Schiede ex Schltdl. had the highest IVI (68.47 %), followed by A. jorullensis Kunth. (21 %) and P. montezumae (10.53 %). These results suggest that the reforested areas would ideally have been planted with P. teocote; however, P. montezumae was the species used. Conclusion Tree structure becomes more complex over time; however, in the short term (five and nine years), the reforested areas cannot yet be considered similar to the reference forest.