The grain of the wood depends on the density of the forest

The grain is the name given to the width of the growth rings. One ring equals one year of growth; counting them gives the age of the tree.

The width of annual growth depends mostly on the density of the trees. The closer they grow, the more they have to compete for light and water, so the less they grow in a year. There are various methods of silviculture.

Timber forest: High density, fine grain

Timber forests (e.g. the Tronçais forest in Allier) are composed of trees of the same age; density is high and the grain (ring width) is tight.

Logs are long, without knots. These oaks are known to have particularly soft tannins.

In the past, the goal of this style of silviculture was to produce timber for building warships. The Tronçais forest in the Allier département was planted by Colbert for the construction of Louis XIV’s royal fleet.

Natural forest: Low density, wide grain

Natural forest (e.g., the Limousin forest): trees are of different ages and density is lower. This dynamic cultivation method produces greater volumes of wood.

Logs can be cut younger (at 120 years old, as opposed to over 200 in a timber forest).

The grain is wider and the logs are shorter. An eau-de-vie resting in casks made from this kind of oak can extract more tannin.