Dendrometric variables and traumatic resin ducts in pine species associated with wood-stripping: a traditional practice in the conifer forests of Central Mexico

Abstract

Background: In La Malinche National Park (LMNP), Pinus species are exploited mainly because they are a non-woody source of products such as ocote (resinous wood chips) and wood.   Questions/Objective: Which Pinus species are subjected to wood-stripping (WS) in the LMNP? What are their dendrometric characteristics? Do WS trees present traumatic resin ducts associated with the ocoteo practice? Does the number of trees subjected to WS increase with altitude? Study site and dates: La Malinche National Park; Tlaxcala, México, 2017-2018. Methods: Random stratified sampling was done in a total of 33 plots in three different altitudes to quantify the number of damaged and undamaged trees and the total height and diameter per tree in each plot. Increment borers were obtained to estimate tree age, samples were taken for taxonomic determination, and tissue samples to evaluate mechanical damage. Results: Pine species subjected to wood-stripping (ocoteo) were P. leiophylla, P. montezumae, P. pseudostrobus, and P. teocote, with P. montezumae being the most affected in high and mid altitudes. WS trees were those with the greatest diameter and with the largest number of traumatic resin ducts. The species having the highest number of traumatic resin ducts was P. teocote. Conclusions: WS intensity in the LMNP is greater in the mid and low altitudes and in trees of greater diameter, height, and age. The species most affected by WS is P. montezumae and all WS individuals have a significantly higher number of traumatic resin ducts.