| Zusammenfassung: | Quercus crispipilis (Trel.) is a dominant tree in mature pine-oak forests of the highlands of Chiapas (Mexico) and Guatemala. Seedlings and saplings of oaks and pines are found in early, open, seral communities, but are infrequent under the closed canopy of dense stands. To better define some of the factors affecting the regeneration of Q. crispipilis in fragmented forests, we studied acorn removal by animals, and the survival and growth of trans-planted seedlings (2 months old) and saplings (30 months old) during a 21-month period in five seral stands (Grassland, Shrubland, and Early Successional, Mid-Successional, and Mature Forest). Seed removal was high in all stands during April-July 1988, but it was lower in non-forested sites when acorns were abundant on the ground (October and November). Survival of seedlings was low in forested stands with deep shade, and mortality was frequently associated with damping-off. Leaf number per seedling increased with time in the open sites, and did not significantly change in the more open forest areas. Survival of saplings in the grassy stand was lower than in the other sites, and sheep browsing and trampling were the main causes of their death. The highest survival and number of leaves were recorded for saplings at the shrubby stand. It is concluded that Q. crispipilis is not able to regenerate under deep shade, but requires open patches in which browsing and trampling by ungulates is absent or minimal. Habitat fragmentation caused by traditional land use patterns in the study area does not seem to hinder, and may even facilitate, the natural regeneration of tropical highland pine-oak forests.
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