January 9, 2023

Laimi Truus, Raimo Pajula

Preparatory work for the restoration of wet forests has started!

With the LIFE IP ForEst&FarmLand project, we have taken on the task of restoring the water regime of wet forests and improving their natural condition over an area of 3,500 ha.

In the first half of 2022 the University of Tartu forestry workgroup selected the priority areas for restoration, while in the second half of the year, the Tallinn University bog forests workgroup started with preliminary monitoring of the areas.

Two large forests in the Alam-Pedja nature reserve – in the Meleski and Peterna-Laashoone areas (almost 2,500 ha in total) and a smaller one (468 ha) in the Ohepalu nature reserve, the so-called Ohepalu 2, attracted the attention of researchers from Tallinn University.

In 2022 the first automatic water level gauges were installed, allowing water levels to be monitored both day and night and throughout the year.

On the basis of a map-based pre-selection the Meleski restoration area was prioritised as the most necessary and least problematic, and Peterna-Laashoone as Class B. Both are deciduous forest areas, and since deciduous forests are the most affected by drainage among forests growing on bog and paludified soils, we give priority to these forests as restoration areas. Both areas are in the flood impact areas of the Pedja and Emajõgi rivers, and the forest there contains extensive and abundant timber resources.

The Peterna-Laashoone restoration area is characterised by moderately to severely drained fen woods and swamp woods. On the banks of the Pedja River there are still small, but mighty floodplain forest stands with old alder, aspen and linden trees, and floodplain-swamp woods with tall stumps and lush grass surrounding the old oxbow lakes.

The name Laashoone (laas = glass) means glass factory. Due to the large timber supply, this forest area between the Pedja River and the Emajõgi River was chosen as the location of the Meleski glass factory, the second largest glass factory in Tsarist Russia, towards the end of the 18th century. Making glass requires high temperatures and a lot of energy, which needs a lot of timber. This is why there are no primary forests in the Meleski and Peterna-Laashoone areas, as these areas have been cut many times over the past 300 years. The last major clearings, including wider and deeper ditches, date back to the 1960s and 1970s, and much of the forest qualifies as a full-drained swamp forest.

It will take time for the results of the Meleski and Peterna-Laashoone restoration activities to become visible. The development of more natural forests will take a generation or two, but the rich wildlife of the area and the forests affected by the Pedja and Emajõgi rivers deserve a better status.

In the Ohepalu 2 area a lush, and in some places broad-leaved, forest has developed on the eskers next to the Udriku lakes on the site of former wooded meadows. Between and to the south-west/west of the eskers, on the Kaansoo side, fen woodlands alternating with fen clearings and reforested clear cut areas spread. The vegetation is lush and species-rich, with abundant orchids – the lesser and greater butterfly-orchid, the marsh helleborine and the early marsh-orchid. Drainage impacts are substantial around Kaanijärv Lake and the old drainage ditches, where full-drained swamp forests alternate with fen woodlands impacted by draining. Drainage impacts are more pronounced in the area of the Kaanjärve-Pala stream ditch and Pala road.

Unlike other Ohepalu areas restored by the Estonian Fund for Nature in the course of the LIFE project ‘Conservation and restoration of mire habitats’ (2015–2021), the water regime of Ohepalu 2 was not restored and it is good that the last section of Ohepalu's biodiverse wetland will return to its natural state.

In parallel with the preliminary monitoring, RMK is preparing the terms of reference for restoration projects. Restoration of the first areas will begin in 2024.

Photos: Laimi Truus