The ecological base and predictability of natural seedling establishment

The more seed trees, the more seedlings

The aim of the project was to study the succes of natural regeneration and manual seeding in upland forests and drained peatland forests, with 25-100 trees per hectare. The seed crop was improved as a function of the number of seed trees retained per hectare. If the aim is to achieve fast regeneration, in less than five years, lots of seed trees should be retained (100-150 trees/ha). The seed crop increases again during the fourth growing season after the stand has been reduced to seed-tree density. Regeneration cutting and site preparation should be timed to take place in the autumn preceding a good seed crop. Another approach is to conduct the regeneration cutting in the winter and site preparation by the following May. Epidemics of shoot disease, poor seed crops after cutting, fast spreading of cottongrass and fast-drying peatmoss (Sphagnum spp) seem to be the major reasons for the poor regeneration results in old drainage areas. In poor seed years manual seeding helped to secure the result of natural regeneration.

Additional information on the project: www.metla.fi/hanke/3233/index-en.htm