The Lautaret Alpine Botanical Garden, a garden and a research centre

Set up in 1899, the Lautaret Alpine Botanical Garden testifies to the one-hundred year history of the University of Grenoble’s passion for alpine flora. The sheer variety in the collections, and the design of the rock gardens set into the landscape, make this altitude garden one of the most beautiful in Europe.

D!CI TV : Jardin alpin du Lautaret from ALTO Dici Radio on Vimeo.

An exceptional natural environment

The natural diversity of species growing in the Lautaret region is due to its extraordinary geographic, geological and climatic configuration. There are over 1,500 species growing in the wild in the three municipal areas of La Grave, Villar d’Arène, and Le Monêtier-Les-Bains.

Geography: a region of major Alpine passes

The Lautaret Alpine Station is located at the very heart of the French Alps right next to Lautaret pass, between the urban centres of Grenoble (90km away) and Briançon (30km away) in the district of Villar d’Arène in the Hautes-Alpes area.

The Lautaret pass is located at 2,058m above sea level and connects the Romanche Valley (a tributary of the River Isere) to the west with the Guisane Valley (a tributary of the River Durance) to the east.

Lautaret Pass (2058m)

The pass has been an important link between the Grenoble and Briançon regions for a very long time. It is vital to the local economy and everything possible is done to keep it open all year round.

The panoramic view that can be enjoyed from the Lautaret pass encompasses:

  • The Ecrins-Pelvoux mountain range with its high peaks (Meije is 3,974m above sea level) and glaciers to the south. This area has been included in the central zone of Ecrins National Park since 1973.
  • To the north, the jagged cliffs of the Grand Galibier mountain range peaking at 3,228m above sea level and breaking off at the Galibier pass, one of the highest and most famous Alpine passes (2,642m above sea level). Located on the border between the Savoie and Dauphiné regions and 7km from Lautaret pass, it offers access to the Maurienne Valley. It is open from early June to late September and is accessed by road from the Lautaret pass.

Geology: a brief overview of the history of the Alps

The Lautaret pass is renowned for its geological panorama where the large Alpine structural units that overlap from east to west with very complex tectonics can be observed.

Climate: a unique location

The Lautaret pass is located close to Briançon, the driest spot in the French Alps, and enjoys an exceptional climate which combines dry summers, lots of sunshine and significant temperature variations.

Distinctive features of the climate:

  • Low rainfall
    Average annual rainfall is roughly 1,300mm at the Lautaret pass, i.e. barely half the amount recorded near Grenoble at the same altitude. Furthermore, the seasonal distribution of rainfall shows a marked trough in the summer.
  • A sun-rich environment
    The area is well protected from westerly winds by the peaks of the outer mountain ranges and from the mists of the Pô plain by the mountains located on the border with Italy.
  • Significant temperature variations
    In summer, temperatures close to 20 -25°C at midday and night-time temperatures of only 2-3°C above zero are not uncommon. The temperature variations are accentuated by the dry air.

Zoning of plant life in the mountains

Anyone who has walked along a mountain path or road will have observed that plant life changes with altitude. This is called the zoning of plant life. The most striking of these changes is undoubtedly the disappearance of forests, which are replaced by meadows, at 2,000 – 2,500m above sea level in the Alps.

Bioclimatic zoning of the French Alps

Biogeographical observations show that major changes in vegetation in the French Alps are structured along three major geographical gradients.

  • The altitudinal gradient determining the zoning of vegetation, moving from the foothill zone to the alpine zone.
  • Latitudinal gradient with the gradual change from the northern to the southern Alps.
  • Transverse gradient with the gradual change from the outer to the inner Alps (the High Romanche, Maurienne, Tarentaise and Durance valleys).

Two climatic parameters have a determining influence on plant growth and development, particularly that of trees: rainfall and temperature (these are called bioclimatic parameters). However, these two parameters vary in a complex fashion along the length of these three geographical gradients.

The fescue hay Meadows

In the non-landscaped areas of the Alpine Garden and the surrounding area of the Lautaret pass, you will observe the hay meadows of Festuca paniculata or ’queyrelle’ which constitute one of the most remarkable groupings in the region. These are known locally as ’queyrellins’.

These subalpine meadows are generally found on gentle, south-facing slopes and at altitudes of below 2,400m (although it can be exceptionally found at 2,500m in protected conditions). It thrives on soft rock (notably flysch) which easily deteriorates and produces deep, relatively fertile, soil at this altitude (the last altitude at which earthworms are found in abundance…).
These meadows have a similar floral composition throughout the southern French Alps

A festival of colour
Festuca paniculata is a perennial tall grass which grows in large dense tufts. The leaves lengthen rapidly at the start of the season. The first leaves start to grow even before the snow has entirely thawed. This usually takes place in the month of May. These first shoots, found growing alongside the crocus flowers, are extremely modest compared to the numerous leaves from the previous year flattened by the snow, which will progressively disappear between May and June.

Vegetation: preserving the region’s exceptional biodiversity

The Lautaret-Galibier region has long been renowned for its exceptional wealth of plant species and populations. Almost 1,500 species (out of the 5,000 recorded species in France) have been recorded here.

Landscapes fashioned by human impacts
The absence of natural forests at the Lautaret pass is linked to the human activities in the area. At some point in the distant past, the areas around the pass were deforested in order to increase the amount of land available for grazing livestock and growing crops. The gentle slopes and the abundant pastures have made this sector a destination of choice for the summer transhumance.

Internships and field courses

Every year the Lautaret Alpine Botanical Garden has a number of openings for interns and students in different fields. These internships and field courses concern students of horticulture and landscaping (horticulture internships), university students (guided visits internships) and university students and researchers (field courses in botany and alpine ecology).