Revista Chilena de Historia Natural 86 (2): 181-190, 2013
RESEARCH ARTICLE
Does disturbance determines the prevalence of dwarf mistletoe
(Arceuthobium, Santalales: Viscaceae) in Central Mexico?
Large vegetation disturbance rates have been reported in the “Zoquiapan y
Anexas” Protected Natural Area in Central Mexico. Arceuthobium globosum and A. vaginatum
coexist within this area and have a deleterious impact on Pinus hartwegii. This study seeks to understand
the relationship between this disturbance and the two dwarf mistletoe species prevalent in this zone. Twenty-four plots
measuring 60 × 55 m containing P. hartwegii trees were selected. Within these plots, the physical features of
the land, the density of host and non-host trees, the prevalence of each mistletoe species, and six disturbance indicators
were recorded. We found that A. vaginatum infests up to 47 % of P. hartwegii trees and that its
prevalence is affected positively by the slope, non-host tree density, and the proportion of stump and dead trees, but is
negatively affected by the prevalence of A. globosum, fi re incidence, waste deposit, and the distance to the
nearest disturbance. Arceuthobium globosum infests up to 37 % of the trees and is affected positively by
altitude, the density of non-host trees, waste deposit and the distance to the nearest disturbance, but is negatively affected
by the prevalence of A. vaginatum and the proportion of dead trees. The prevalence of both mistletoe species
within the study area is governed by the physical environment, the anthropogenic disturbance and the negative interaction
between these mistletoe species. Disturbance has an important impact on mistletoe populations, modifying their
prevalence; so it is primordial to understand this relationship in order to propose control methods.
Key words:
disturbance indicators, interactions, logging, parasitic plants, Pinus hartwegii.
