Chestnut

Botanical name Castanea sativa Mill.

Historical and cultural information
On the southern side of the Alps, where chestnut trees have been growing for thousands of years, their wood is used in construction, viticulture and for manufacturing windows and furniture. The staves of chestnut barrels destined to wine ageing contain too much tannic acid, slightly more than oak. For this reason chestnut wood was once used to extract tannin for leather curing. During the traditional process of producing balsamic vinegar, fermentation, which is the middle phase of 5, must take place in chestnut barrels. This gives the vinegar its delicate and penetrating aroma.

General information
Chestnut trees bear fruit only after approximately 20 years. The plant has average dimensions and in close forests, the trunks are long and with rich foliage; isolated plants have a wide crown and short trunks. They can reach an age of various centuries. As an arboreal species of Mediterranean origin, chestnut requires a mild climate, not too dry, sort of “vine-like”, although it can also stand the shade. Chestnut trees grow at a rate double the oak. Chestnuts, rich in starch, used to be the daily bread for many before the potato was imported. The dried fruits were ground into flour and used to bake bread. In some places the poor had permission to plant chestnut trees on public ground for personal use.

Characteristics
Chestnut wood is similar to oak in colour and structure, however it is easily distinguishable because the medullary rays aren’t visible to the naked eye. This timber has typical ring porosity, in which the ring of spring vessels isn’t clearly distinguishable. The brown colouring is more delicate than that of the oak.

Properties
Chestnut wood is of average weight (dry density 530 kg/m3) and Brinell hardness rates at 18 N/mm2. It has low shrinkage levels and good stability. The timber is difficult to dry as it is prone to cellular collapse. It is easy to process, and can be glued with good to satisfactory results; it is also easy to polish. Contact with iron can produce colour alterations. It has very good durability thus rating as second class.

Use
Chestnut wood is used as indoor and outdoor construction timber, for structures in contact with water and boats. It is also used for veneering, panelling and parquet. In some countries it is used to make barrel staves.