Influence of litter on emergence and early growth of Quercus rugosa: a laboratory study

Species-rich old-growth forests dominated by Quercus were extensive in the highlands of Chiapas until a few decades ago. Current land-use is resulting in replacement of Quercus by Pinus spp. in the canopy of the remaining for est fragments, which are less diverse, drier, and more exposed to freezing temperatures. Forest floor and soil are also modified and may limit the reg eneration of many woody species. We studied the influence of litter type (p ine needles vs. oak leaves), litter depth (0, 3, 6 and 14 cm), and litter c over (3 cm vs. 0 cm of loose litter on top of sowed acorns) on the emergenc e and growth of seedlings of Quercus rugosa, a dominant tree in pine-oak fo rests. Seedling emergence and establishment were affected by the interactio n of experimental factors. Uncovered acorns on pine litter were more expose d to desiccation; this effect was more evident with deeper litter. Acorns s owed on oak litter were not affected by levels of litter cover and litter d epth. The results can be of use in defining further field studies, and prac tices of direct seeding for restoration of pine-dominated stands.