A guided migration of beech trees in need of protection from climate change is bearing fruit after thirteen years in France, with saplings now adorning the former First World War battlefield of Verdun.
Some of the beech trees, planted in 2013 after two years in the nursery, are now three meters tall as they emerge from the mist in their reddish-brown autumn colors on what was a shell-ravaged hellscape 100 years ago.
“What is crucial is the survival rate, which we have achieved here to more than 90 percent” – a big improvement on the 80 percent usually considered the mark of a successful plantation, said geneticist Brigitte Musch.
“We shouldn’t get ahead of ourselves, they are only about 10 years old,” she added. A hard frost or overgrowth of clematis is still capable of wiping out the young trees.
Experts from the French Forestry Authority (ONF) regularly check the saplings to ensure they are growing, healthy and able to withstand the local wildlife.
The plot of beech trees of less than one hectare is part of a plan to ‘migrate the genes’ of trees at risk of dying in the south of France, where the climate is becoming increasingly drier and no longer able to support them .
Musch, head of genetic resources at the ONF, recalls how the project grew out of the idea of climate analogs at a 2011 meeting.
Using data and knowledge from UN climate experts on where seeds grow best, this method allows forestry experts to map out which areas will have a hospitable climate for different types of trees in the future.
The map of France for 2050 is alarming for lovers of the majestic beech, which can live for several centuries and spread its shady crowns up to 40 meters high.
Other traditionally widespread trees, such as the oak, are also at risk of disappearing from many French regions as the climate changes.
– Massive bombardment –
In Verdun, the beech trees have passed the first tests of their new home, taking root in calcareous soil that had long ago become hard-packed and filled with metals and toxins due to the intense bombing of the First World War.
“On average, six shells fell here for every square meter. This was right on the front line in 1916. It was so rough that it had to be leveled with excavators so we could get there,” Milene said. Mahut, a local ONF official.
After 1918, the forest was replanted with resinous trees such as pine – partly thanks to seeds sent by Germany as reparations – and later with deciduous trees, especially beech and sessile oak.
Now the new rows of beech trees fleeing the south are arriving faster than the usual speed of tree migration.
The International Union for Conservation of Nature (IUCN) estimates that oaks and beech trees migrate naturally about 100 kilometers (60 miles) in 500 years.
According to the ONF, this is about ten times slower than the rate at which the climate is changing, which underlines the need to give the trees a helping hand.
Musch, who wrote her dissertation on the recolonization of Europe by oak and beech after the last ice age about 10,000 years ago, has immersed herself in her research to mimic the natural process.
The beech fascinates her because of its ability as a species to “grow on wind-battered rocks, bring in biodiversity and even be invasive.”
– ‘Promise of rebirth’ –
The ONF project has been named Giono, after the French author Jean Giono, whose book “L’Homme qui Plantait des Arbres” (“The Man Who Planted Trees”) tells the story of a shepherd who brings a mountain back to life with thousands of new trees.
Giono himself fought in the Battle of Verdun, in which hundreds of thousands of men were killed and wounded on both the French and German sides over the course of ten months.
Oak acorns and beechnuts of notable specimens have been collected since 2011 in the French regions of Provence, Sarthe, Allier and Deux-Sevres.
The Maas region, where Verdun is located, was chosen for the new planting because of the less dry climate and relatively mild winters.
Climate change has also caused some local species such as spruces to suffer, including from attacks by bark beetles.
“There is no one solution to climate change; assisted migration is just one of them,” Musch said.
Mahut, who tends the new beech trees on their small plot, sees the growing trees as “a promise of rebirth” for the badly abused land.
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