Efecto de las podas sobre Arceuthobium spp. en bosques densos y semidensos de Pinus hartwegii (Lindl.)

Abstract

Mistletoes are one of the principal pests in temperate forests of Mexico, and pruning has been implemented as a strategy for their control and to prevent their propagation. The objective was to determine the effect of pruning on population of dwarf mistletoe (Arceuthobium spp.) in semi dense and dense forest in the natural protected area of Nevado de Toluca, Mexico. Twenty six plots were selected in dense and semi dense forests with and without pruning. In each plot, normal diameter (ND) and height (H) of trees were determined, as well as their percentage and degree of infestation, comparing sites with and without pruning during three years of evaluation. Semi dense and dense forests correspond to a secondary and guided succession respectively, with statistical differences (p < 0.05) between size of trees with and without pruning. Percentage of infected trees by dwarf mistletoe did not show significant statistical differences among the three evaluation periods, in dense (4.7%) and semi dense (12.2%) forest. Both types of forest without treatment were significantly different in the percentage of infested trees in the three periods of evaluation, registering the major percentage of infected trees in the degree of infection 1, 2 and 6, the diameter classes ≤ 20 cm being more susceptible to the attack of this pathogen. Pruning reduces the incidence of dwarf mistletoe in semi dense and dense forest, and its effect was permanent during the evaluated period.