Abstract

ENDARA-AGRAMONT, Angel Rolando et al. Factors associated with the spatial distribution of dwarf mistletoes in two Pinus hartwegii populations in Central México. Rev. Mex. Biodiv. [online]. 2022, vol.93, suppl., e935008.  Epub Dec 09, 2022. ISSN 2007-8706.  https://doi.org/10.22201/ib.20078706e.2022.93.5008.

Dwarf mistletoes (Arceuthobium globosum and A. vaginatum) represent a threat to the Pinus hartwegii forests distributed in the high parts of mountains in Mexico (3,000-4,200 m asl). The objective of the study was to determine the factors associated with the presence and levels of infestation of such mistletoes in 2 mountains of Mexico. Two thousand, two hundred and fifty-four sampling sites were established, 1,622 in the Nevado de Toluca Flora and Fauna Protection Area and 634 in Monte Tláloc, to register the presence and degree of infestation of regeneration and adult individuals (≥ 7.5 cm DN). The data obtained in the sampling sites included geographical location, altitude, slope, slope orientation, the dominance of the herbaceous and shrubby strata, presence of dead or damaged individuals and infestation by bark beetle (Dendroctonus adjunctus). A correlation test was performed to identify the factors related with the presence of mistletoes, in addition to a principal component analysis. This study revealed that dwarf mistletoes infest 37% of the forest area; the presence of bark beetles and the site orientation are the main factors that influence on the infestation of mistletoes in the studied forests.

Keywords : Conifers; Parasites; High mountain pine; Regeneration; Infestation levels.