Species list


Castanea sativa

Sweet chestnut

Sweet chestnut (Eng), castaño (Spa), castanyer (Cat), gaztainondoa (Baq), castiñeiro (Glg), castanheiro (Por).


DID YOU KNOW...? The scent of the male sweet chestnut flowers is very similar to that of human semen.


The sweet chestnut tree is a rapidly growing tree that can be up to 30 m tall, may develop an impressively thick trunk and live a very long time (some specimens are a thousand years old). Its trunk is thick, solid and sometimes hollow in older specimens. The bark is brown, dark and fissures longitudinally with age, acquiring an obliquely grooved characteristic, as if the trunk were twisted. The leaves are simple, deciduous, alternate, oblong-lanceolate, 10-25 cm long, 5-8 cm wide and serrated along the margin. The flowers appear in summer. The male blooms are grouped into long, narrow, yellow strands (catkins). The female flowers are arranged at the base of these and, after fertilisation, contain the seeds (chestnuts) in a spiny cover known as a burr.


This species prefers cool places, deep soils in mountainous areas with some moisture throughout year, and non-extreme climates, i.e., it suffers in Mediterranean summer droughts and intense winter frosts. It can grow on acidic or leached, lime-free substrates, from sea level up to 1800 m. It may form extensive low-montane stands thanks to its ability to resprout from stumps, even in specimens cut off at ground level.


It was thought that the chestnut was native to the areas of the Caucasus, Balkans and Asia Minor. On the Iberian Peninsula, it is most abundant in the north and northwest, but there are excellent stands in the south. The pollen fossil record indicates the existence of the sweet chestnut in this area prior to the last glacial period. However, nowadays it is naturalised in some provinces and present throughout almost all the peninsula thanks to it being extensively cultivated by the Romans. There is still controversy over whether this species was already naturally occurring in some isolated valleys in the north of the peninsula. The anthropologist Juan Luis Arsuaga, in The Neanderthal's necklace: in search of the first thinkers, writes: “...some of these trees, specifically the chestnut, cherry, walnut and stone pine, may not be native to the peninsula. They were introduced within historical memory, from the time of Romans onward, for the economic value of their fruit. Although it had been thought that prehistoric man of the Iberian Peninsula had never come across these plants, there is a fossil record predating the last glacial maximum of chestnut, walnut and stone pine. It is possible that they became extinct with the arrival of the most intense cold and were then reintroduced, but it is equally possible that they survived in certain refuges and subsequently recolonised the peninsula, although they were indeed given a helping hand by man”.