The Mortes and Bellefontaine Lakes

Works to build the church started in 1634. The massive appearance of this structure is amplified by the narrowness of its openings. It is covered with a metal shingle on its most-exposed outer walls. The church has been registered on the complementary inventory of Historical Monuments since 2 March 1981.

100 to 200 million years ago, we would have travelled here by boat, on a tropical sea. Then limestone particles and shells slowly started to gather on the waterbed, gradually forming limestone layers. During the Tertiary Period, these layers started to lift, fold and soon gave birth to the Jura Massif, with its relief comprised of folds and plateaux.

Opposite you, the Roche Champion cliff marks the edge of the Risoux massif and separates Switzerland from France. Before the 16th century, neither of these two countries wanted to claim the Jura, which was covered in forest. However, as the area was progressively cleared for agricultural purposes, competition for this land stepped up a notch. The Reform later exacerbated this rivalry, creating a political and religious rift between Switzerland and Protestants on one side and Franche-Comté and Catholics on the other. The Catholic cross that can be seen atop Roche Champion asserts this religious belonging.

At the end of the Quaternary Period, the Jura was covered by a huge glacier. Reindeer and mammoths were abundant. This mass of ice changed the relief and broke and moved rocks. When it melted, the ice left glacier moraines in the watertight rocky holes left behind. At the bottom of the depression, a lake later took shape, fed by the water from the melting glacier, from rainfall and from streams. Before long, the climate started to warm up. Aquatic plants quickly developed and organic matter accumulated. The lake filled and turned into a marsh.

The stream you have crossed comes from the Cives combe. It is joined by another stream from the Risoux slopes (the mountain looming over you). After travelling underground, the stream surfaces near Morez, around ten kilometres from here. From there to here, it passes through the peat bog, with the latter acting like a sponge during rainy weather and when snow starts to melt. By doing so, the peat bog limits flooding, and then gradually returns the water during dry periods. Its last function is to purify the water running through it by acting as a filter.

In 1639, the plague wreaked havoc in the region. In Chapelle-des-Bois, it killed roughly fifteen of the 150 village inhabitants. Fearing that they might catch the illness, survivors did not want to bury the dead in the cemetery. Their decision to bury the plague-ridden corpses in the peat bog is no accident. Considered worthless land, and rarely used for agricultural purposes, the peat bog seemed the ideal place to bury victims of the plague without contaminating the land.

Sedges (or carex) grow and help stabilise the soil. Later, sphagnum peat moss takes over and forms a dense carpet. These are species of moss that grow continuously and that provide an accumulation of organic matter on which sphagnum peat moss is able to grow. The vegetation becomes compact and creates the black and fibrous bogs resembling garden compost. However, this phenomenon is painfully slow and it takes thousands of years for a peat bog to reach a height of just a few metres.

Peat bogs are valuable history books for pollen specialists or palynologists. In fact, pollen is well-preserved in peat bogs, and some pollen found there can even be thousands of years old! From the oldest layers deeper down to the surface area, palynologists are able to retrace the history of plants in the peat bog and its surroundings all the way back to prehistoric times. Which trees used to grow in the forest? Which plants did man grow for food or for clothes? By analysing pollen, we can learn all of these things.

From the top of the rocky bar overlooking the Chapelle-des-Bois valley and its village, your eyes will view a wide landscape, from the combe of Cives to the north, to the two almost twin lakes that are the Lac des Mortes and the Lac de Bellefontaine to the north. The hydraulic regime of both lakes is quite particular: during high waters, the Lac de Bellefontaine’s waters overflow into the Lac des Mortes; however, during low waters, the water in the Lac des Mortes feeds the Lac de Bellefontaine.

The tracing of the borders, following the Paris Treaty of 1815 was symbolised by landmarks linked together with a low dry wall. However, the border has not always been watertight, and it symbolises what has come to be a lifestyle. More than a border, the Franco-Swiss frontier, which runs along the Risoux ridge line, is a place of passage and of exchanges, both lawful and unlawful, over time. 

“Gîts”, steep trails where the wood exploited on the Risoux used to be discarded, also served as a passageway to Switzerland. These Gîts were given a name, and some have an entire history; the Gît de l’Echelle, the Gît d’Entre-Deux-Roches... During the 19th century, smuggling activities enabled some to live entirely off the unlawful trading of consumer goods that could be found at a lesser cost on one side or the other of the border. The Gît de l’Echelle, despite its steepness, served in particular as a passage for resistance fighters and intelligence officers and saved Jewish families during the Second World War thanks to the temerity and bravery of local smugglers, both French and Swiss.

Like other Jura peat bogs, those of the Les Mortes and Bellefontaine lakes are a testament to the glacier that covered the Jura twenty thousand years ago and that left in its wake impervious moraines. These impervious depressions filled with stagnant water and were populated by plants. On the soft soil of the peat bogs grow some plants that are particularly suited to this environment (Cranberry, bog-rosemary, cotton grass, Drosera, etc.).

Comme d’autres tourbières jurassiennes, celles des lacs des Mortes et de Bellefontaine témoignent du glacier qui couvrait le Jura il y a vingt mille ans et qui a laissé des moraines aux fonds imperméables. Ces dépressions imperméables se sont remplies d’eau stagnante, et ont été peuplés de végétaux notamment les sphaignes, sorte de mousse. La masse végétale se tasse et forme la tourbe, noire et fibreuse ressemblant à du terreau de jardin. Ce phénomène est très lent : des milliers d’années sont nécessaires pour atteindre une hauteur de quelques mètres.Sur le sol meuble des tourbières, quelques plantes particulièrement adaptées peuvent croître (Canneberge, Andromède, Linaigrette, Drosera …). Les eaux du lac des Mortes forment un court ruisseau, d’à peine plus d’un kilomètre, et se perdent (ou se meurent) dans une anfractuosité au cœur du hameau des Mortes. Ces eaux ressurgissent quelques kilomètres en aval au lieu-dit « Le Trou Bleu » à Morez. Le belvédère de la Roche Bernard offre un panorama spectaculaire.  Les deux lacs de Bellefontaine et des Mortes reflètent le ciel et viennent trancher nettement sur le fond vert clair des pâturages, sur le roux des tourbières et sur le vert sombre des boisements qui entourent la Combe de Bellefontaine comme une marée déferlant depuis l’horizon. Le contraste, ici, est frappant entre l’aspect sauvage de la forêt et le côté policé des pâturages entourant les quelques fermes et hameaux. La situation du belvédère lui-même, adossé à la sombre forêt du Risoux, et dominant un à pic, accentue la sensation de hauteur, de vertige, on surplombe réellement le paysage.

This small carnivorous plant has hairs covered with a type of glue. When an insect comes into contact with the plant, it finds itself stuck and cannot escape. The leaf trap then slowly closes-in on its prey, and secretes digestive juices that digest the insect. This adaptation allows the plant to acquire supplementary intake in this environment in which roots struggle to find enough food. It is also called common sundew, due to its appearance.

From the blueberry family, it grows in “raised” peat bogs and is slightly acidic. Its berries are not as sweet as blueberries. It is the plant that is host to the moorland clouded yellow, a beautiful yellow butterfly which, when in caterpillar form feeds on the bog bilberry.

The waters of the Les Mortes lake form a short stream barely one kilometre-long before disappearing into (or dying in) a crevice at the heart of the “Les Mortes” hamlet. These waters are drawn just under ten kilometres downstream from the Arce source in Morez and serve to provide part of this High-Jura town’s population with drinkable water.

This house’s roof is pierced through the top by a “Tué”, a wooden pyramid-shaped chimney measuring at its base about 3 metres wide and at its summit around 1 metre wide. The Tué, which is positioned near the centre of the house, is a room caught in a draught, where all of the smoke gathers, and serves as a pantry, ensuring that sliced meat in particular is well preserved. To learn more: The Michaud farm ecomuseum in the Combe des Cives (Chapelle-des-Bois) ecomusee-jura.fr/

You have now exited the wooded meadow and have come across vast stretches of wild land. Wild? Well, not really. If you look closely, Man has left his mark on this landscape. Farms are scattered here and there and tell the story of how the High Doubs was “colonised’. In this area, where winters are long, home-based craftmanship, wood carving or clock-making developed to keep the peasants busy when the cold season forced them to stay inside.  

The vast landscapes you are in are natural prairies, in which biodiversity is particularly abundant and contributes towards the production of PDO (Protected Designation of Origin) cheeses. Farmers in Chapelle-des-Bois and the surroundings are particularly aware of this and ensure that the unicity of these landscapes is preserved by using suitable practices.

In the hamlet of “les Landry”, you will pass in front of a house that tells of some of the architectural history and construction techniques used in the High-Doubs. Years of “playing around” with wood, stone and metal.

Agricultural buildings are scattered throughout this landscape: old farms are found alongside much larger modern agricultural buildings that house Montbeliarde cows. These cows produce the milk that is used to produce local cheeses.