Natural Features of Leivonmäki National Park

Light-filled esker forests

Eskers, lakes, mires, forests - all typical features of Central Finland’s nature can be found in Leivonmäki National Park. You can familiarise yourself with all this on nature trails in the park during a single visit. The most rugged forests of the park are located in Syysniemi, at the northern tip of the area. Hietajärvenkangas around Selänpohja and the Joutsniemi area are home to old pine forests. The same chain of eskers continues south of Lake Rutajärvi as Haapasuonharju, which has a length of several kilometres. In the pine forests of Leivonmäki, you may hear the beautiful singing of mistle thrush or see as a black woodpecker is carving a nest hole for itself.

The long and narrow eskers in the area were formed during the last Ice Age as the glacier was melting. The Ice Age ended 10,000 years ago. Eskers make diverse habitats for vegetation. The conditions of the habitats vary according to the direction and steepness of slopes. The esker forests of Leivonmäki mostly consist of open, dry pine forests. Shady "suppa" holes on the slopes of the esker are marks of large blocks of ice, which got buried in the sand during the Ice Age. 

On the northern border of the national park, in the central and eastern parts of Syysniemi, forests are more spruce-dominated and the mires smaller. In this forest-covered area, the nest holes carved by woodpeckers also provide homes for tits and flying squirrels. 

Fruits of the nature at Haapasuo mire

The call of cranes in spring is a sign that snow is already melting in the Haapasuo mire. During the spring, other birds nesting at the mire, such as European Golden Plover (Pluvialis apricaria), Wood Sandpiper (Tringa glareola) and Hen Harrier (Circus cyaneus), also return from their wintering grounds.

In the summer months, the large continuous stretches of Haapasuo in the southern part of the national park is teeming with life. The middle of Haapasuo is characterised by stunted trees and its vegetation is adapted to high and fluctuating water levels. Peat moss (Sphagnum) and Hare’s Tail Cottongrass (Eriophorum vaginatum), which can be easily recognised from its fluffy white seeds in June, are the most typical species growing at the open mire. 

Shrubs such as the Bog Whortleberry (Vaccinium uliginosum), Leatherleaf (Chamaedaphne calyculata) and Dwarf Birch (Betula nana), thrive in the pine-dominated mires at the edges of Haapasuo. 

Cloudberry (Rubus chamaemorus), Cranberry (Vaccinium oxycocos), Bilberry (Vacciunium myrtillus) and bog whortleberry are also common at the mires. 

Conservation has not always been a top priority in Haapasuo. In the 1960s, ditches were built in the mire for forestry purposes. The aim was to drain the mire and to boost the growth of forest species, such as pine. Protecting original nature is the guiding principle in the management of national parks and for this reason, the ditches have been blocked and the mires restored. The changes have been quite rapid: peat moss (Sphagnum) and hare’s tail cotton grass are again growing at Haapasuo and, as in the past, you need rubber boots when walking there. 

Haapasuonharju Ridge, on the western side of Haapasuo Mire, is dominated by rugged dry pine forests, where the good Lingonberry (Vaccinium vitis-idaea) harvest attracts people to pick berries in the autumn. Like in Syysniemi, in the middle of the more than 100-years-old pine forests you can see small esker lakes, and a diverse tree stand grows in depressions and "suppa" holes, which were made by melting ice after the Ice Age. The sandy Vartijamäki road on Haapasuonharju Ridge is a great scenic road through the southern part of the park. The emblem bird of the National Park, the European Nightjar (Caprimulgus europaus) nests in the old sunny pine forests. Haapasuonharju Ridge is the most important territory area for the Nightjar in Central Finland.

The European Nightjar at Leivonmäki

When walking on an esker during the light-filled nights of early summer, you may hear a sound resembling the whirring of a spinning wheel. The almost nonstop sound is the mating call of a nightjar (Caprimulgus europaeus). The bird is only on the move in the night and during daylight hours it rests on a tree branch or on a fallen trunk, relying on its camouflage. In the hours after sunset, nightjars hunt night butterflies and other nocturnal insects.

Nightjar does not build a nest as it lays its eggs on a shallow recess on the ground. The species prefers dry pine forests and pine forests on eskers and in rocky terrain. Nightjars nest on the Haapasuo esker in Leivonmäki every year. 

Nightjar is well-adapted to changes in weather during Finnish summers. As not many insects fly in rainy and cool weather, a lack of food is a real risk, so the nightjar enters torpor where its body temperature may drop to below 10 degrees Celsius. August–September is the time for nightjars to return to the warmth of the south. They return to Leivonmäki from the African savannas in May–June.

Numerous islands and untouched shores

Lake Rutajärvi (surface area 1100 hectares) divides the National Park into two parts. Lake Rutajärvi is a clear lake with very little aquatic vegetation. Water horsetails and reeds can be seen along some parts of the shoreline. The shores are varied: mires, flood marshes, rocky areas and eskers. The beaches are very rocky in some places – especially on the Syysniemi side.

Its water level has been lowered twice in the end of the 1800s, 4 metres altogether. Following the water level drop, many small islands were formed in the lake. They are important for landscape and nature conservation reasons. The rocky old shoreline can be seen, for example, along the trail going to Joutsniemi.

The nesting birds of Lake Rutajärvi include the Black-throated Diver (Gavia arctica), the Whooper Swan (Cygnus cygnus), the Common Sandpiper (Actitis hypoleucos), Great Crested Grebe (Podiceps cristatus) and Red-necked Grebe (Podiceps grisegena). The Goldeneye (Bucephala clangula) nests on small peaceful lakes.

Rutajoki River

Lake Rutajärvi and Lake Päijänne are connected by Rutajoki River with many rapids. Lake Päijänne is 45 metres lower, so at some places the rapids are steep and waterfall-like. The rapids also make the water rich in oxygen, and therefore Rutajoki River is an important breeding area for the Brown Trout (Salmo trutta lacustris), which needs oxygenous water. Rutajoki River has been cleared and a dam built in the upper course. However, the surroundings have stayed almost in their natural state.