presented on Auciust 10, 2001. Title: Recruitment of Ponderosa Pine Seedlincis

The objective of this project was to investigate the fate of ponderosa pine regeneration from seed to established seedling, and to determine the relative influences of several important stand elements on those fates. The project was carried out in a series of observational and experimental recruitment studies in central Oregon. In an analysis of the temporal and spatial patterns of seedfall during one season, viable seeds accounted for 62-73 percent of all seeds, and seed density averaged more than 1 million per hectare. More than half of all viable seeds fell within the first 30 days. Seedfall occurred more rapidly at the more mesic site. The less mesic site produced more seed, and the denser stand within each site yielded more seed. Seedfall patterns within each stand were not spatially uniform. At the two stands of moderate densities, the relationship of seed density to distance from trees followed a negative binomial distribution. In an observational study of germinant emergence and survival, about 3 percent of viable seed resulted in emergents. A small fraction of germinant