Pre-commercial thinning creates more growth space for trees

Pre-commercial thinning should be carried out when spruce trees reach a height of 3–4 metres, pine trees a height of 4–7 metres, and silver birch trees a height of 4–5 metres. The stands are usually 10–15 years of age at this point.

In addition to maintaining growth, pre-commercial thinning is needed to safeguard the quality of the growing stock, as it helps create more growth space for better trees. In conifer stands, this means removing broadleaved trees hampering the development of coniferous trees, as well as poor-quality trees, trees growing too fast, and conifers growing too close to each other.

Broadleaved trees, especially silver birches germinated from seed, are left in conifer stands to increase biodiversity and to achieve the desired overall density. Other broadleaved trees that are valuable for biodiversity are also left in suitable places without completely removing any species growing in the stand.

Pre-commercial thinning is carried out in accordance with the Finnish best practices for sustainable forest management. The density of the stands remaining after thinning must not exceed the desired density by more than 20 per cent. If the density of the remaining stands exceeds this upper limit, Metsä Group will carry out the repair work free of charge.

Timely pre-commercial thinning reduces costs

Pre-commercial thinning should be carried out at the right time to avoid an increase in costs due to delayed thinning, as well as reduced forest growth. An even stand where trees have enough space to grow will reach the first thinning phase much sooner than an unthinned stand. After properly performed pre-commercial thinning, the growing stock can develop undisturbed until the first thinning phase.

It is possible to receive kemera subsidies for pre-commercial thinning. Our forest specialists can tell you more about subsidies, and they can also handle the related notifications and applications. We apply for all subsidies directly for the forest owner.