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Management of swamp forests

The management of swamp forest areas should be planned as a whole, and it includes timely forest management and fellings, as well as water protection structures, ditch cleaning and supplementary ditching, fertilization and the construction of possible bank roads. It is recommended to implement it as a joint project with other landowners if the swamp area is divided between several properties.

Ditch cleaning and supplementary ditching refers to the opening of old ditches and the excavation of possible supplementary ditches. Ditch cleaning and supplementary ditching becomes topical when the condition of ditches and the evaporation of stands are no longer sufficient to maintain a sufficient groundwater level at a depth of 30–50 cm during the growing season. Usually, it is 20 to 40 years since the previous ditching. 

If the groundwater level is too high, it slows down the growth of trees, but the water level that is too deep increases the carbon dioxide and water emissions caused by the decomposition of peat. For ditch cleaning and supplementary ditching, it is possible to receive Kemera aid.

The need for ditch cleaning and supplementary ditching in the area can also be reduced by using forest management methods based on continuous cover forestry. In this case, the aim is to keep the groundwater level at a suitable height by utilizing the evaporation of trees. In the cultivation of an even-aged swamp forest, ditches are usually cleaned 1-2 times in the rotation period. 

In order to reduce the nutrient pollution and suspended solids load in water bodies, ditch breaks are made in connection with ditching, and sedimentation basins and overland-flow fields are built. In addition, only ditches necessary for silviculture will be opened. It is not recommended to open the ditches of the most nutrient-poor habitats, because it is not economically sensible to grow forests there.   

Nutrient deficiencies are common in swamp forests. In peatlands, stand growth is limited by the lack of phosphorus, potassium and boron. Nutrient deficiencies are remedied by ash fertilization or fertilization for which it is possible to receive Kemera aid. Fertilization is carried out either by helicopter or as a land-based fertilization. 

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