Secrets of the forest

Today’s politicians, routinely accused of opportunism and a lack of long-term vision, could do worse than to consult the historical example of 17th-century French statesman Jean-Baptiste Colbert.

Colbert was a minister during the reign of Louis XIV, taking on the key roles of Controller General of Finance and Secretary of State for the Navy in the 1660s. His main mission was to bring order and efficiency to a notoriously chaotic and wasteful country – and, in particular, to set the nation’s forests in order.

He began an eight-year survey of the woodland around Tours in 1661, and was horrified by what he found: deforestation, frequent fires, cattle grazing everywhere. ‘France perira faute de bois,’ – ‘France will perish for lack of wood’ – he warned starkly in his 1669 work, Ordonnance des Eaux et Forêts. In an age when naval strength was vital to geopolitical power, France’s chronic timber shortage was a massive weakness.

Colbert’s philosophy of ‘bon usage de la nature’, with its emphasis on sustainable development, was based more on pragmatism than eco-ideology: manage woodland correctly and the result would be tall, narrow-trunked and straight-backed oaks, providing the perfect material for shipbuilding.

Dappled shade: Forests like Loches in France have been nurtured for centuries

But it was no short-term fix: the benefits from the forest planting and management programme that Colbert initiated would only be reaped when the oaks reached maturity, some 200 years later.

Today, in the dappled shade of Loches Forest, south of Tours, Colbert’s blueprint lives on, maintained by the forest guards of France’s l’Office National des Forêts (ONF). But now, some of the main beneficiaries of this painstaking work are not shipbuilders, but cask manufacturers.

Traditionally, casks made from this fine-grained sessile oak (Quercus petraea) are destined for the winemakers of Bordeaux and Burgundy, but whisky makers like Gregg Glass of Whyte & Mackay are now getting in on the act too.

The company’s Jura Seven Wood, launched last year as part of a wholesale revamp of the island single malt, uses casks sourced from six different French forests: Vosges, Jupilles, Les Bertranges, Allier, Tronçais and Limousin.

Each forest lends its own distinctive note to the mix, from the mocha and red fruit of Vosges to the unctuous peach and mango of Les Bertranges and the brooding astringency of Limousin. In flavour terms, these are great building blocks for the blender.

Black death: Lead from bullets fired during the First World War has infected this wood

There’s far more than provenance to the work that Glass has done on oak with cask supplier Demptos – oak sub-species, grain type, toasting regime and so on – but there’ll be time to explore all of that soon enough on Scotchwhisky.com. For now, let’s focus on the trees.

Jura Seven Wood started life with cask trials almost a decade ago, and some of the liquid has been matured for 17 years in total (10 years in ex-Bourbon before an extended ‘finish’ in French oak). But that timescale pales in comparison to the management programme in Loches Forest.

There’s a saying that making a cask takes ‘two centuries, two years and two days’, referring respectively to the typical life of the tree, the seasoning process and the final manufacture of the cask. For great wine you need great grapes; for a top-quality cask, finding the right tree is a must.

In Loches, this is where Fabien Daureu and his fellow gardes forestiers (forest guards) weave their magic, because straight-trunked, 200-year-old oak trees don’t come about by accident.

The keys are slow growth – 2mm a year is ideal – meaning narrow trunks and fine grain; straight trunks and no low branches, which would create knots in the wood.

Rosy future: A genetic anomaly makes this wood more valuable for cask manufacture

So Fabien and his colleagues visit each block every 10 years, deciding what to cut and what to keep. In the first decade, there might be 700,000 or even 1m oaks per hectare; by the time 250 years have passed, that number will have fallen to 50.

It’s a Darwinian process of dominant and submissive trees, where the former rob the latter of light, and fierce competition leaves no space for low-growing branches, forcing trunks to rise ramrod-straight in search of the sun.

There are tricks – beech trees can give shade and stop the summer sun from causing imperfections in the wood – and there are surprises, both good and bad, which only emerge once that two-century process is over and the tree has been felled.

At the Sogibois stave mill near Bordeaux, these secrets are revealed. The bad: split logs riddled with black and rendered useless by lead bullets embedded in the trees during the First World War; and the good: the rosy-hued wood created by the genetically mysterious presence of carotenoids, which break down into norisprenoids and create a prized fruity flavour that commands a higher price in the form of the Essencia casks made by Demptos.

Back in Loches, after 200 years of careful management, the next oaks to be felled stand proudly, well-spaced, in what looks at first like an otherwise deserted part of the forest. But look closer and you’ll see vast numbers of young saplings pushing up from the floor, less than the height of a man, renewing a process that will, given time, create the wine and whisky casks of the mid-23rd century.

And you thought making whisky was a long-term process...