I get many questions about oak and barrels. So I made up some answers:
Are we cutting down all the trees in Europe to make barrels?
Where does all this oak come from?
Who owns all this forest and how is the wood sold?
What are the important species of oak for the cooper?
What is the relationship between air-drying and toasting?
The old adage about "lies, damned lies, and statistics" holds true with
forestry statistics. First, getting statistics is not easy in a
forest. Second, few countries - the usual suspects so to speak -
can afford to inventory forests on a routine basis. For many countries
the statistics must be regarded carefully.
Since 1947 around two million hectares of land have been re-forested.
Unlike other countries, where ancient stands of hemlock, spruce and fir
have been cut down to make toilet paper and diapers, France has done a
good job of managing its forests since World War II. Supplies of French
oak -- barring unusual circumstances such as dramatic climate change--
should remain abundant. France has been managing its forests for
centuries and on the whole a good job has been performed.
Almost a quarter of France, or nearly 14 million ha, is forest,
constituting more than 40 per cent of all forest in the European
Community. About one third of this forest land is oak. There are
2,600,000 ha of Quercus sessiliflora and Quercus robur, the two species
of oak of interest to the cooper, of which at least 2,000,000 hectares
are located in the regions important for barrel staves. It was
estimated in 1986 that there are 430 million cubic meters of these two
species of oak growing in France. Now the figure runs to 570 million
M3! Usually there are 3 cubic meters of growth for every cubic meter
cut down. Some coopers say that the main problem for the coming decades will be getting enough of tight-grained wood. Go to Top
Many people say to me, "I\'ve been to Nevers and I didn\'t see any lumberjacks". Where does this wood come from?? There is no appellation controlé but much confusion of nomenclature in the world of oak. This means not only that winemakers are suspicious about proclaimed wood origins but that people use different definitions for the same name. Some would include wood from the western Loire in the category of \'bois de centre\' while others would exclude anything but Nevers and Allier. Others will classify wood around Nevers with wood from the Yonne and Cote d\' Or as \'Bourgogne\'. I have asked many coopers for their definitions of what is what. Rarely do I get the same answer! Of course, if coopers had to supply topographical maps with each order not much work would ever get done. The following forest regions in Northern France provide oak for wine and brandy barrels. The ONF website has some very good maps.
Limousin
Woods from the following regions in western France are usually called
Limousin: The eastern part of the departments (Napoleon created
departements, which are administrative areas) of Deux-Sevres, Vienne,
Hautes de Vienne,the northern part of the Correze,the Creuze,the
eastern part of the Charente and the southern part of the Indre. This
is an area near the city of Limoges,not that far from Cognac.
These regions tends to produce oak with wide grains because q robur is
dominant here. Soils here tend to clay/limestone or granite. These
woods are more tannic than the tight-grained woods and are most popular
with brandy makers.
Western Loire and Sarthe
Woods from forests in the western Loire, from the departements of
Indre, Cher and Indre-et-Loire, and in the Sarthe near Le Mans, have
tight grains and are highly prized. This area is north of the Limousin
region.
Nievre and Allier
Woods from these two central departements near Sancerre go by many
names. Sometimes this wood is sold under the name of the specific
forest. Troncais, for example, is a government-owned forest north of
Moulins, while Bertranges is a forest near Nevers. This sort of oak may
also be sold under the name of the region, such as Allier and Nevers.
To many French coopers however all of this wood is regarded simply as \'bois de centre\', wood from the centre of France; others would exclude
Nevers from the category of center of France but include forests in the
Western Loire. However these forests are named, the wood is
usually tight-grained and is popular for both brandy and wine. Soil
here tends to silica and clay. As stands are planted with close spacing
the trees are said to grow up, rather than out; hence the tighter
grains.
Vosges
Wood from the Vosges forests west of Alsace became popular with
wine-makers in the early 1980s. This wood is usually tight-grained and
resembles the oak from Nievre and Allier. Oak experts say they can
identify this wood by its \'clear\' or \'white\' colour. However, the
character of Vosges woods varies according the altitude of the
stand. Compared to wood from Nevers and Allier, Vosges tends to be
wider-grained.
Jura and Bourgogne
Just to the east of Burgundy are forests which traditionally supplied Burgundy with oak. These forests are still important.
Argonne/Ardennes
Located near Champagne, this forest provides a small amount of oak for
the cooperage business, principally for those few champagne producers
who still ferment in barrel. It is rumored that sometimes this wood is
sold as Vosges or Bois de Centre. There are over 340,000 hectares of
oak forest here, which provided 330,000 M3 of oak in 1987. Because of
military action in this region during the two World Wars, oftentimes
this wood cannot be safely sawn, as the shrapnel ruins the saw.
The following chart is lifted from an article by Mr. J-P Lacroix of
the
ONF in Dijon. Although
it\'s
a little out of date it gives an idea of
where the trees have been harvested and probably not much has changed
since then.
Region:
1987 Oak harvest Hectares of
oak
Bourgogne/Burgundy 407,000
M3 624,000
Departements of Nievre,
Cote d\'Or, Yonne, Saone et Loire
For those of you who have failed
to memorize the departements
of France, let me say that this
region would stretch from Chablis
south to Beaujolais and includes
that area around Nevers.
Lorraine
398,000
m3 265,000
Departements of Meurthe et Moselle,
Meuse, Moselle, Vosges.
This would include what we usually
group together as Vosges.
Center
393,000
m3 517,000
Eure-et-Loire, Loiret,
Loire-et-Cher, Indre,
Cher,Indre-et-Loire. If you
have visited the Chateaux
of the Loire, you have been
in one of these departements.
Champagne
331,000
m3 342,000
Ardennes, Aube, Marne,
Haute-Marne
Franche-Comte
226,000
m3 253,000
Doubs, Jura, Haute-Saone
Territoire de Belfort
M. Lacroix considers Allier as its own region and notes that it is
relatively small, compared to the Nievre. Via the good services
of Mme. Noelle Francois, of Francois Freres, I have recently obtained
the following statistics relating to the production of stavewood in
1991 from Mr. Lacroix.
Merrain:
Bourgogne/Burgundy:
4,888 m3
Center (Blois, Fontainebleau): 5,303 m3
Poitou, Charente:
5,175
m3
Limousin:
2,833 m3
Aquitaine:
4,237 m3
This region includes the greater Bordeaux region, including the Gers. Traditionally wood here is used for Armagnac barrels, but it is said that some coopers in the Bordeaux area use it for making wine barrels.
Allier:
1,966 m3
Vosges:
6,596 m3
A total of 30,000 M3 of stavewood (\'merrain\') was produced in 1991 from
150,000 m3 of logs. This represents a potential of 300,000 barrels. In
1992, following serious frost in France, production of stavewood was
down 20% Go to the Top
A potential buyer bids on the trees in a delineated section, which
should be at least 100 and preferably well over 120 years old before
providing suitable wood for casks. The buyer has the right to go into
the forest, measure the trees, even to bore into them 30 cm to see how
straight the grains are. He must decide how much of each type of wood
there is, how it can be used, and, of course, how much he should bid.
As not every tree in and auction lot can be used for staves, French
cooperages usually work with wood brokers who will have other
customers. The most valuable part of the tree is that which can be used
for paneling, followed by cooperage and furniture. What the coopers and
the paneling people cannot use might end up as railroad ties or
firewood. The furniture and construction industries are also important
customers. Go to the Top
There are hundreds of species of oak, all of which can be broadly
separated into two categories, red and white. The red oaks are porous
and cannot therefore be relied upon for watertight cooperage. For wine
three sorts of white oak are most important, one American and two
European, all of them belonging to the botanical sub-group Euquercus.
About the two European species:
1.Quercus sessiliflora, also known as sessile oak, Quercus rouvre or Quercus petraea.
2. Quercus robur, also called pedunculate or variously English, French and Russian oak.
3. Quercus alba, also known as American white oak. This general
name is also applied to other American oak species, including
Quercus bicolor, swamp white oak; Quercus lyrata, overcup oak; Quercus
durandi, Durand oak; Quercus michauxii,swamp chestnut oak;
and Quercus prinus, chestnut oak. Some of these species can
hybridize with each other.
Oak as a species is rich in tyloses, which are structures that plug the
tubes. This is what makes it particularly good for holding liquids, as
the path of the liquid through the wood is blocked by these tyloses.
American white oaks, such as Quercus alba, are the richest in these
tyloses, which is why the barrel staves can be sawn into shape without
risk of leakage. With European oaks there are fewer tyloses so the wood
is more porous and must be split to follow the tubes and then bent so
that all the tubes are parallel to the stave, thus minimizing leakage.
These European oaks grow throughout Europe, as far east as the Urals,
as far south as Sicily, as far west as Ireland, France, and Portugal,
and as far north as southern Norway.
Quercus sessiliflora can reach a height of 25 m and can live over 300
years. Branches form high up the relatively straight trunk. Wood from
this tree is usually tight-grained. This species grows well in sandy,
silty soil with good drainage, but grows well in a variety of soils. In
Europe it is found thoughout the United Kingdom and from France east to
Poland and the Baltic states and as far south as Italy and Yugoslavia.
Quercus robur, thought of as English or French oak, also grows to over
25 m in height and can live over 300 years. Its branches spread out to
provide more shade than Quercus sessiliflora and it tends to produce
wide-grained wood. It prefers fertile soils where there is plenty of
water. As Quercus robur tolerates a wider range of growing conditions,
it is more widespread in Europe than Quercus sessiliflora. It extends
further north into the Scandinavian countries, further south into
Turkey, Georgia and Portugal, and east as far as the Urals. Wood from
this species tends to have wider grains than Quercus sessiliflora
although the two species can be positively distinguished only by
examination of leaves and acorns. The acorn of Quercus robur is
attached via a long peduncle whereas that of Quercus sessiliflora is
attached directly to the twig. There is so much cross-fertilization
that there are many hybrids of these two species however.
Coopers do not usually distinguish the two species in their workshops.
Like wine-makers they tend to pay more attention to forest location and
grain size than oak species. And, as wine-makers increasingly
understand, details of barrel manufacture can have an even more
significant effect on wine quality than exact forest location. Trees on
the outside of the forest will grow out rather than up while on the
inside of the forest the opposite is true.
Go to the Top
Most people –including veteran winemakers – don’t understand how air-drying of the stave wood impacts the perception of toastiness in wine. Years ago I arranged an experiment at a famous winery, whose name is being withheld in the interest of national security.
We arranged for barrels of three toast levels and three air-drying periods to be made.
When we eventually tasted the wine in these barrels we noted that the longer the wood was dried, the less toasty the wine appeared, regardless of toast level. As a general rule it can be summarized that
--the longer the wood is dried the more subtle the flavor and the more supple the texture will be… hence the saying the more you pay (for the longer drying), the less you get
--very short air drying periods give flavors on the smoked meat side of life with more astringency
This is evidence gathered from an informal experiment. To do an experiment on this subject for a formal study would cost over $100,000.
When winemakers ask us for suggestions as to barrel type we always turn the question around?? How long are you keeping the wine in barrel?? What percentage of new barrels are you using?? A long time in barrel combined with a high percentage of new oak calls for well-seasoned wood.
Go to the Top