Effects of structural retention harvesting on seed production and seed characteristics of old-growth eastern white pine (Pinus strobus L.) stands in northern Ontario

Abstract

Seed production and seed characteristics were examined during a mast seeding year in unmanaged, old-growth eastern white pine (Pinus strobus L.) stands located in northeastern Ontario and compared with those in adjacent stands partially harvested 16 years earlier using a structural retention system. Seed yields from old-growth stands were comparable to those of mature, second growth white pine stands but seed production assessed relative to unit area (# ha-1) and pine basal area (# m-2) was lower in partially harvested stands. In both unmanaged and harvested stands, seed production rate of trees growing in localized areas of lower pine basal area was higher. Seed characteristics and seed viability did not differ between harvest treatments. Although structural retention harvesting reduced seed production, results suggest that supply and viability of seed are unlikely to limit seedling recruitment in managed or protected old-growth white pine forests. Key words: germination, old-growth forest, partial harvest, seed mass, seed production