Nouvelle-Aquitaine has a million hectares of forest planted to stop the sand
The Landes forest is the largest planted woodland in Western Europe and it was made to fix the sand of a coast that was on the move. It worked everywhere except at the Dune of Pilat, which at 106.60 metres keeps advancing into the pines.
If you cross southwestern France along the Atlantic coast you will spend two or three hours seeing nothing but pines. Straight, identical, in rows, kilometre after kilometre. The natural assumption is that it is a forest.
It is a public work. And it was built against a specific enemy: sand.
01 What was there before: water, sand and stilts
Well into the nineteenth century, most of this strip was flat, waterlogged, sparsely populated ground. The name says it: 'landes' means heath or wasteland, from a Gaulish root for uncultivated land.
The economy was pastoral and hard. Only sheep rearing and the manure they produced made it possible to grow rye, and wet winters forced people to cover the ground with brushwood to preserve it until the next sowing.
And to move over that soft, flooded ground, the shepherds used stilts. It is not a folk curiosity: it was the reasonable way to cross terrain where walking meant sinking. The image disappeared along with the heath and was replaced by another, the resin tapper with his tools.
02 An 1857 law and ten thousand square kilometres of pine
The first plantings were made in the eighteenth century, in the Pays de Buch, within present-day Gironde, with two aims: to halt erosion and to drain the soil. But the transformation at scale came with the law of 19 June 1857.
That law ended traditional pastoralism and set in motion a massive reforestation, conceived at once as land drainage and as economic development. The result is what you see today: some 10,000 square kilometres, nine tenths of it a maritime pine monoculture.
At its centre a patch of natural forest survives, inherited from the post-glacial woodland of this part of France, where pine coexists with oak, alder, birch, willow and holly. It is concentrated along watercourses, where drainage works best.
03 The dune that would not be stopped
The system worked along almost the entire coast. Once the sand is fixed by vegetation, the dune stops moving and the forest consolidates behind it. But there is one stretch where that did not happen, and it is the most famous on the coast.
The Dune of Pilat, at the southern entrance to Arcachon Bay, measured 106.60 metres above sea level in 2018. It is Europe's tallest sand dune. It is some 500 metres wide from east to west, 2.7 kilometres long from north to south and has a volume of the order of 60 million cubic metres.
The name is recent. Until the 1930s the spot was called 'Les Sabloneys', the new sands, and it was a property developer who renamed it, taking the Gascon word 'pilhar', meaning heap.
04 A hundred and six metres moving inland
What makes this dune exceptional is not its height, it is that it moves. The prevailing westerly wind pushes sand up the windward face, carries it to the crest and drops it down the leeward face, which is the one facing the forest.
The result is that the whole thing advances inland and covers whatever it finds: pines, houses and roads. On the eastern face, the sand line cuts the pine wood with no transition, and the trees left at the edge appear buried to half their height.
That the movement is old is confirmed by maps. Those of 1708 and 1786 show places named Pilat located to the south and offshore of where the dune stands today. That is: it is not in the same place it was three centuries ago.
05 A forest that falls all at once
A planted forest, of one age and one species, has a weakness a mixed forest does not: everything responds the same way to the same blow. And the blow came in January 2009.
A major storm damaged some 300,000 hectares of forest in France, and 90 per cent of that area was in the Landes. At the Dune of Pilat a gust of 175 kilometres per hour was recorded on 24 January that year.
The other transformation is slower and less visible. Since the 1970s, parts of the forest have given way to intensive agriculture, mainly cereals. The landscape that looks immutable has been changing use every few decades for two hundred and fifty years.
06 How to look at it
The first practical consequence is that you do not need to find a viewpoint to understand this region: just look at the rows. The pines are aligned because they were planted, and the age of each plot can be read in the thickness of the trunks.
The second is that the Dune of Pilat is worth climbing for the side nobody photographs. The view towards the ocean is the postcard one; the one that explains the place is with your back to the sea, watching the sand move into the pines.
And the third is a correction of vocabulary. This is called a forest and works like a crop field: it is planted, pruned, clear-cut and replanted. Knowing that does not make it less interesting, it makes it legible.
