IberiaNature A guide to the natural history of Spain
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The holm oak and the dehesa

Holm oak - encina (Sp) alzina (Cat) Quercus Ilex (Lat)

The holm oak is an essential, almost defining, element of the Spanish Mediterranean landscape. It has been said that the tree was until recently as important to the Spanish peasant as the seal was to Eskimos. Hyperbole apart, the encina was certainly a cornerstone of traditional culture. Antonio Machado, the 20th-century Spanish poet put the importance of the tree in these terms (my clumsy translation):

"El campo mismo se hizo árbol en tí, parda encina"
"The land (1). became a tree in you, brown oak (2). "

R. Moro in his excellent "Guía de los árboles de España" (1995) proposed the holm oak as the national tree of Spain , in the way that the maple is to Canada . He gives a number of reasons. (I paraphrase)

  1. Spain has exceptional examples of 700 years or more, growing to gigantic sizes well above average.
  2. Because the encina is found in almost every province, and covers 25% of the forested surface area of Spain .
  3. Because it is an excellent producer of wood for charcoal and for parquet. It also bears immense quantities of acorns to feed our flocks and herds of livestock in the autumn, which most years are dry.
  4. Because it is the fundamental element of the dehesa , the rational form of agriculture of Dry Spain, making use of its fruit and its foliage and branches, and also helping to improve the poor soils which are enriched through the dead leaves and detritus of the tree.
  5. Because the encina provides an excellent environ for small and big game.
  6. Because it survives forest fires well, and easily sprout from stumps.
  7. Because the encina adapts to most soils.
  8. Because the tree prefers a dry clime, which is the norm in Spain .

La Encina y La Vaca/ The Holm Oak and the Cow) by Joaquín Mir i Trenxet 1915

The encina is believed to be the climax species of the true Mediterranean forest, which once stretched over great swathes of Spain. This virgin forest has long-since disappeared through grazing, charcoal-burning and felling. A few patches of something approaching this vast primeval forest survive on isolated higher slopes and particularly in the Sierra de Guara on the edge of the Aragonese Pyrenees and in the Sierra Morena in Andalucia. Many of these forests grew on poor and arid soils, and when felled these could not support agriculture for long and were soon abandoned to be taken over by maquis and garrigue, which covers much of Spain and the Mediterranean in general today. However, elsewhere in Spain and parts of the Maghreb , instead being felled, huge forests of holm oak were thinned out, creating the sparse pasture parkland known as dehesa, which together with evergreen cork form a unique man-made, managed and bio-diverse ecosystem. These are grazed on by the classic Iberian pigs and to a lesser extent by cows and sheep. Dehesa often combines holm oak with evergreen cork trees, as the latter bears its acorns in winter, providing a staged supply of animal food. A hybrid between the two trees (known as a mesto ) bears acorns between the two peaks, giving a constant supply. See article on the dehesa

Dehesa landscape with free-range Iberian pigs

Incidently and coincidently, the origin of the name of the town of Alburquerque (of which the USA's Albuquerque is just a varient) comes from Latin Alvus quercus, or white oak - 'encina blanca', which it bears on the town emblem.

Quercus Ilex is considered to be two separate species:
1. western holm oak (ssp. Ballota - yes that's Ballota not Bellota, known in Spanish as encina or carrasca ), the classic sweet-acorn producing oak of the south-western and central dehesas , and also present in Morocco and France ;
2. the holm oak 'proper' (ssp. Ilex ) which is more prevalent in northern Spain from Asturias to Catalonia , and the rest of the Mediterranean .

The term Quercus comes from the Celtic Kaërquez , meaning beautiful. Ilex comes from Latin, and means precisely holm oak.

The biggest and oldest holm oak in Spain

La Terrona

Locals from the village of Zarza de Montánchez in Caceres have always known and loved La Terrona , perhaps the oldest and biggest holm oak in Spain. It took a bolt of lightning to bring it to the attention of the outside world. The lightning split the tree in two and almost killed it. Biologists came to the rescue and discovered that the tree is perhaps the oldest and biggest holm oak in the country: it's 16.5m tall, with a girth of 7.8m and is 800 years old. The village's ex-mayor claims they used to be an even bigger one: La Governadora, but it was burnt after also being hit by lightning 27 years ago. Although the biologists may have saved the venerable old tree from a natural death, its newly-found fame has brought new dangers, as unscrupulous tourists are causing serious damage. The Spanish postal service paid tribute to the Terrona in February 2004.


1 countryside sounds far to tame a thing to describe the landscape Machado was talking about. Countryside translates better as campiña, which is restricted in Spain to small areas like L'Ampordà in northern Catalonia , described by the Catalan poet Josep Plà as a 'middle-class landscape'.
'Country' alone I felt would be ambiguous.
2 maybe brown encina would sound better. 'brown holm oak' sounds too technical, better to say 'brown quercus and totally ruin it.