Continuous cover forestry involves the maintenance of a forest canopy at all times, in contrast to the currently predominant clearfelling-based management methods. The new Forest Act of 2014 lifted the restrictions applied to the use of selection and patch harvesting instead of clearfelling.
Forestry without clearfelling
Continuous cover forestry is forest management without clearfelling. A substantial part of the trees is always retained in harvesting. Single-tree selection is the most small-scaled alternative among the harvesting and management regimes. After the felling of individual large trees, the remaining trees acclerate their growth, and new trees grow from the undergrowth reserve and more emerge through natural regeneration. In spruce forests the removal methods used include selection felling and small patch selection felling. There are no established methods for pine stands, but an application of two-storied management with prolonged retention of standards seems most promising. Continuous cover forests are thinned with a heavy hand and grown as relatively sparse stands so that the undergrowth and small trees remain in good condition and the regeneration works.
Small forestry costs – timber production capability smaller than in forest cultivation
The timber production capability reached in continuous cover forestry is not as high as in even-aged forestry. In spite of a smaller yield, continuous cover methods may still be economically viable options. Management costs remain small when hardly any cultivation measures or tending of seedling stands is needed. Furthermore, the revenue from felling is not decades away as it is after clearfelling. However, the primary reason why forest owners may choose continuous cover methods is that they wish to avoid the drastic change clearfelling causes, in spite of the reduced timber production capability.
Felling is done with the common fully mechanized harvesting methods, but it is more difficult and slightly more expensive. In addition, damage to the growing stock cannot be completely avoided. The risks are reduced as loggers gain more experience and the harvesting methods develop further. Annosum root rot, a fungal disease that rots and kills trees, is a big problem in continuous cover forestry. When an infection has infected a forest site, it can only be eradicated by clearfelling and subsequent change of the tree species.
Research based on a unique series of trials
The Natural Resources Institute Finland (Luke) carries out research on continuous cover forestry, beginning with its biological and technical foundations all the way to its economic, social and ecological impacts and operating models. One of its most important areas of research and development is the adaptation of forest management to climate change. The Natural Resources Institute Finland has access to a unique series of trials, where different continuous cover methods have been tested, and the development of trees and forests have been monitored through accurate measuring for several decades.
The research material generated by the Natural Resources Institute Finland is used for purposes ranging from practical operations all the way to the setting of strategic guidelines for forest management and political steering. On the basis of scientific data, the Natural Resources Institute Finland produces solutions and operating models for continuous cover forestry, and provides them to users in the form of recommendations and guidelines for forest management, information applications (such as the Motti software) and training packages. We also apply the same research methods to our international operations in California, Tanzania, Great Britain and the Nordic Countries, for example.
Picture on top of the page: Erkki Oksanen / Luke