Uncovering continuous cover forestry
Diving into continous cover forestry: what it stands for and how so
Definitions of Continuous Cover Forestry (CCF) may be different according to different authors and sources. It may also have different definitions across the globe, Europe, and within the Central and Eastern Europe region itself. Many times, legal definitions are also different from scientific ones, which confuses foresters, advisors, scientists and the general public. Our set of articles on the matter has a general target to look at what CCF may or should mean across the region and how to approach it.
Continuous Cover Forestry may mean the continuous and uninterrupted maintenance of the forest. In other words, it can be the use of silvicultural systems whereby the forest canopy is maintained at one or more levels without clearfelling. The main aim is, after all, to maintain woodland climate conditions on-site at all times.
The term ‘low impacts silvicultural systems’ (LISS), which is a bit broader than CCF, may include management practices like small coupes, coppices with or without standards, and minimum intervention. CCF, which at some stage was also called ‘alternatives to clearfell (ATC)’, sits within the LISS group. The difference is that CCF is a bit stricter, and LISS is generally better for light-demanding pioneer tree species. An example: small coupe felling may not be classed as CCF, but it is clearly a LISS technique. The technical distinction is the interruption of tree cover. In the CCF scenario, it is limited to a quarter of a hectare, whereas in LISS, it could be up to two hectares. A quarter of a hectare is defined because that is deemed to be the maximum size where if the canopy is removed completely, the forestry climate is still maintained.
In the clearfell scenario, there are four very clearly defined stages following each other: restocking, tending and thinning, final harvesting, and fallow stage. In CCF, we only have two stages, tending and thinning as the first stage, which is usually rather long, and regeneration and final harvesting as the second stage, and these cannot be clearly separated from each other because they happen simultaneously at any one site. There is no fallow stage at all in CCF.
So in a CCF scenario, the management method looks aligned to that of clearfelling, except for the absence of the last stage, known as fallow, which is followed by restocking. In CCF, this is otherwise replaced by a final harvest and a regeneration stage.
This is really what sets CCF apart from clearfelling, as two management stages are happening at once. Final harvesting is a staggered approach in CCF. At the same time, the next generation of trees is introduced to the site. In a CCF scenario, it is more likely to grow bigger trees because they are usually kept on site a bit longer.
In CCF, the stand must be prepared for the transformation phase, which means that tree stability needs to be adequately developed by opening up the canopy. Usually, in CCF systems at this late stage, the canopy is opened to let light in, to allow natural regeneration, and to help the next successful stand to grow up underneath the canopy of the predecessor stand. That means the canopy needs to be reasonably open, and the trees need to be stable.
The right species composition is also of paramount importance (“the right trees in the right place”). The best trees should be left on site for longer to promote them as sources for the next natural regeneration, for which optimal conditions should be provided. Individual tree selection ensures the survival of the best trees, which will then be the parent generation for the next stand. This is a lengthy selection process that includes respacing and thinning.
It is, of course, always desirable to keep and grow the best trees on site, even in the clearfell scenario, but it is of paramount importance to do so in CCF.