The commons in the early times of Castile

The frontier between Al-Andalus (the Islamic territory in the Iberian Peninsula) and the Christian kingdoms was by the course of the river Duero in the 10^th century. Accordingto the law of the Siete partidas (codification of law under the late thirteenth century king Alphonse X), all property won from the enemy was at the disposal of the king, who could distribute it at will. As these territories were practically deserted, the Castilian monarchs initially tried to attract settlers to the newly-conquered areas by creating huge municipalities and by offering generous land concessions to their chief military, ecclesiasticsupporters and Military Orders (Mangas Navas, 1982).

In a first stage, the lands conquered from the Moslems by the Castilian-Leonese kingdom were divided into small municipalities and distributed between a large number of settlers. Conversely, the extensive territory further south, between the river Duero and the river Tajo, was largely vacant for a long time, having been depopulated as a result of warfare. From the 12^th century, the Christian kingdoms moved towards the south; the territory was repopulated with a smaller number of settlers, granting the municipalities huge territories (Clemente Ramos, 2000).

The lands that had not been apportioned through royal grants remained as Crown property (crown lands or tierras realengas). These tracts were usually extensive lands of an inferior quality, often uncultivated, because the best lands were normally the first to be disposed of in royal grants. Managed lands tended to follow a ring-shape pattern, with the more intensively cultivated orchards located in the ring close to the settlements, followed by the extensive cereal fields, the grazing pasture lands and, finally, the woodlands.

The new settlers formed towns under royal (realengos) or seigniorial jurisdiction. The colonists used the lands individually as far as possible, but, often, a large land portion remained uncultivated (baldíos), free for a common use. The baldíos were typically woodlands (monte) of a varying density and had a variety of uses: pasture, wood, hunting, acorns and other wild fruits, and even arable agriculture. These landswere of an uneven quality, ranging from marginal areas to fertile soils and remained ownerless merely because of their low local population density or of their physical isolation (Vassberg, 1984).

The legal ownership of the baldíos was problematical from the very beginning since nobody held any legal titles to them. For centuries, they were often claimed by the monarch, by the municipalities and by the nobility. Normally, it was recognized that the baldíos were at the disposal of the monarch, although the use regulation of baldíos was assumed to be a competence of municipalities. For instance, special permission for cultivation had to be obtained from the village government, whilst the residents were allowed the grazing and revenue collection (Argente del Castillo, 1991).

Apart from the lands owned by the Crown and the private properties, there were some community properties owned or used by the Castilian municipalities. These properties fell into two juridical categories: common property, set aside for the free use of the local residents (ussualy defined as comunes or commons, and, at some extend, with baldíos), and propios, i.e. lands or any other kind of property owned by the municipality as a juridical entity, which were treated as private property. The propios were usually rented out by the town council, using the income to pay for public works or local taxes. Common property (comunes or baldíos) was, at least theoretically, for the free use of the residents of the municipality. Nevertheless, land tenure categories in Spain constitute, in fact, a complex pattern: this difficulty in delimiting the significance of each item has led to continuous disputes throughout history. There is no chance of clearing up these concepts: comunes was a confused term that was used indiscriminately along with baldíos. These categories played a significant role in the shaping of rural landscapes in Spain because of the different intensities in resource use.

Dehesas and pasturelands in the Middle Ages

Medieval Castile was the most pastoral society in Western Europe. It has been calculated that, by the fifteenth century, two-thirds of the production land in Castile was devoted to grazing (Payne, 1973). More than two million transhumant sheep and an undetermined number of sedentary livestock grazed across the Iberian Peninsula (García Sanz, 1998). The Mediterranean-type climate, however, caused dramatic limitations for livestock; pastoralists had to constantly move around in order to prevent the exhaustion of their resources. Ecology and culture combined to make migration a compulsory feature of Iberian pastoralism.

Domestic grazing regimes took on different forms, which co-existed in the same village. The first was sedentary livestock rearing; secondly, transhumance, where the flocks roamed, usually in a bi-annual régime between summer pastures in the north and winter grazing lands in the south. Accordingly, high plateaus and mountain areas were reserve zones where transhumant herds could find forage, water and shelter from the scorching Mediterranean summer. This semi-nomadic system took advantage of the mountain pasturelands, which were at their bestthroughout the summer. Stocks could cross almost the whole of the Iberian Peninsula by means of an elaborate network of trails called vías pecuarias, the cañada being the best known of these pathways. However, most of the flocks remained near the villages, so it was necessary to devise a system to supply them with pasture resources.

Common municipal pastures were part of the solution for the herds, especially for local livestock. Municipalities possessed a complex set of lands that were used for pasture (Vassberg, 1974). The most widespread of them were the ejidos and the dehesas. The ejido (derived from the Latin exitus, meaning exit) was a land area situated just outside the town reserved as pastureland for the local residents. The dehesa (from the Latin defesa, meaning fenced) was land that was fenced, at least theoretically, and usually destined for pasture. Though the term dehesa did not strictly suggest common or private property, it is probably to be originally conceived as a communal system of protection of grazing for residents, particularly for draught livestock, such as oxen. In time, a distinction was made between the dehesas dehesadas, subjected to strictly individual uses, and the dehesas concejiles, in which only certain uses, such as pastures, were privatised, the communal use of certain forestry resources being maintained, such as acorns and water (Clemente Ramos, 2005). One important feature characterizing this first dehesa is that, although a forest tree cover would frequently cover it, this was not an essential trait of its definition.

Much of the Spanish grassland was (and still is) located in woodlands, in montes. Unlike the juridical significance of the words baldíos, comunes, ejidos and dehesas, monte is a forest and geographical concept, which may mean either forest woodland or a mountain. Many of the pasturelands already described —ejidos and dehesas— should have been partly or even wholly in the monte, so there is no means of properly distinguishing one category from another. The montes provided a large number of outlets: not only was there pasture grass growing between the trees, but there was also a valuable pastoral resource in the leaves and small branches of certain trees and shrubs, and the holm oak acorns were a highly prized food, particularly for swine. The practice of ramoneo, whereby herders helped their animals to graze green shrub leaves by cutting down some branches, was widespread in the montes to complement pasture resources.

From June onwards, or even before, the wild pastures became dry and of little value for grazing. In order to complement grazing resources, there was another important pasture source, which was well-suited to the complementary relationship of traditional livestock husbandry and agriculture, the custom of stubble grazing, called, in old Spanish “derrota de mieses”. Derrota meant that when there were no crops growing, the fields, whether in stubble or in fallow, would be treated as common pasture. Accordingly, private rights to a field were limited to the period between planting and harvest. As the prevalent traditional farming system in Spain was not annual cropping, but biennial, triennial or usually longer fallowing rotation period systems, the total grazing-friendly area was relevant in each territory. This system led to the fresh stubble (rastrojos) and fallow (barbechos) of grain fields becoming valuable resources because this pasture contained harvest residues and spontaneous vegetation developed during the fallow period. In short, derrota, baldíos and commons (such as ejidos and dehesas) encouraged almost the entire territory of a village to become a continuous commons open to the local livestock, and even to that of outsiders.

During the Reconquest, the danger of Moslem raids in some areas made livestock a better investment than easily-destroyed crops and vineyards. Hence, ranching expanded a great deal in the new frontier settlements. The creation in 1273 of the powerful Honourable Council of the Mesta, an association of sheep owners is further evidence of the early strength of the livestock industry (Klein, 1920). The wool trade was the major source of wealth for Castile during the medieval period; it also had the advantage of being easily taxable. The advent of merino sheep in the fourteenth century increased high-quality wool production and the Mesta, exporting wool to textile factories in northern Europe, carried on a huge trade. The Mesta flocks could have grazed throughout Castile, only keeping them away from five preserved lands: cropping fields, vineyards, orchards, meadows, ejidos and dehesas boyales. Baldíos were open to the Mesta flocks in accordance with the earlier royal regulations, but as the term was ambiguous, some towns were able to assert their authority over these tracts, defending their use as commons.

The Crown was concerned about the necessity of fencing pastures: Alfonso X (1252-1284), at the peak of the Reconquest, allowed the use of three aranzadas of land per pair of oxen (roughly 1.8 ha) from the tierras realengas, as dehesas in each municipality. The population growth, the spread of arable land and local conflicts led to aproliferation of dehesas, which were established by the Crown via local government. This Crown protection was essential for municipalities and private properties, because grazing by transhumance herds was forbidden (Linares Luján et al., 2003). However, the wool trade grew and became of outstanding importance to the royal economy, and the size of herds increased exercising their pressure upon the baldíos and putting a stop to fences.

There were different categories of dehesa. In the Medieval and Modern ages, every Castilian municipality had at least one common dehesa; in that case, those pastures were created for draught oxen, dehesa boyal, a fenced pasture reserved for plough oxen, which were the most frequent draught animals before the sixteenth century. When mules gradually replaced oxen as the most prevalent ploughinganimal, they were allowed to share the use of the dehesa boyal (Vassberg, 1974). The dehesa boyal would usually be located near the village, in a site where there was pasture, shade and water. As a rule, this pastureland was reserved for the exclusive use of local animals; its integrity was frequently under menace, to the extreme that a law was issued in 1438 to prevent illegal livestock being taken into the dehesa boyal. Municipalities could own other dehesas that were not specifically boyales (Salomon, 1964). Some of these were open to all animals without any discrimination, while others were reserved for the exclusive use of certain types of animals (for instance, dehesa yegual o caballar, for mares and their young, and dehesa carnicera, reserved for butchers’ herds in order to provide better, cheaper meat).

In the period between the XV century and the end of the XVI century in the municipalities in western Spain, one could distinguish between an initial circle that included closed spaces and common lands/ejidos, a second sector of cereal crops, vines and collective spaces, and a third one for extensive livestock farming, with dehesas, marginal agricultural spaces and monte. The first circle contained the ejidos (land demarcated for use by communal livestock, intended for self-supply of residents or for use by the village as a whole, except for oxen, which had their own space) and fields for vegetable gardens and vineyards, which took the shape of a multicrop system with dispersed trees that gradually took over the land of the ejidos. The second circle included open fields, cereal croplands and vineyards without trees, together with the common lands: dehesas boyales (for beasts of burden – oxen and asses), dehesa caballar (for military use, found in villas and cities for use by the oligarchy) and different kinds of cotos or dehesas de la carnicería, spaces intended for animals for consumption. Cereals were grown following a rotation system of año y vez (two-yearly) that allowed communal use of stubble and integration of agricultural and livestock farming uses. In the third circle there was a predominance of the livestock farming and forestry uses including other dehesas: delimited private lands mainly used for rent of pastures for large herds of livestock, whether or not in transhumance.

The size, location, and local use of the dehesas differed in terms of their geographical and historical factors. It was probably desirable to have trees in the pastures because they provided protection from sun, wind and rain, and branches could be used as emergency forage during drought periods, but this was not a sine qua non feature of the character of dehesas.

Acorns constituted one of the major benefits of the dehesas, in the frequent cases that contained oak-trees. Acorns were not only used as food for animals, but in famine years they were also consumed by humans as acorn-bread. Not all montes and dehesas had oak trees, certainly, but those that were rich in these trees were prized for their acorns because a flourishing swine livestock could be maintained (Parsons, 1962). City and town councils usually supervised and regulated acorn harvests to guarantee maximum profits.

The dehesa was, therefore, in early times not strictly a pasture land with dispersed oaks. In fact, there was an old Spanish term for this, monte hueco (which could be translated as “hollow forest”), defined as land in which there were sparse oaks and other trees and from which, when looking down through their canopy, one could freely see to some considerable distance below (Grove and Rackham, 2001).

The dehesas during the Spanish Empire

The Spanish forest surface lessened continuously after the Middle Ages (Bauer, 1991). The need for more agricultural land increased deforestation, accelerating the loss of woodland. Deforestation was also carried out for construction, firewood and, notably, for shipbuilding. The woodlands suffered as well during the wars since they could cover up enemy movements. As has been argued, the rise of the Spanish Empire took place against the background of an intensive environmental change (Braudel, 1975; Simmons, 1989).

The monarchs of Castile increased the Mesta privileges. A 1501 law (Edicto de Posesión) declared that all lands upon which the transhumant flocks had ever grazed were to be reserved in perpetuity for pastures and could never be used for any other purpose. In 1528, a royal regulation stipulated that local governments could not deny their commons to the Mesta flocks unless the Crown had reserved the land (Sánchez Salazar, 1988). Only in the late 15^th century the Crown stopped favouring the organization and start to take into account the increasing anti Mesta movement. Its grazing rights were reduced, as a consequence of a change in Castilian economy.

The Mesta and the local peasants had an antagonistic relationship. Initially, this was not probably a typical arable-pastoral conflict, but a fight for the use of the same pasture resources between transhumant and sedentary livestock. The local municipalities and peasants wanted to defend their pastures for their own use and the protection of the baldíos under the legal concept of dehesa was a reliable method to obtain this. Later, with the expansion of cereals, vineyards and olive crops in the sixteenth century, the farmers put some pressure on traditional pastureland by invading transhumance lands such as baldíos,cañadas or dehesas. Any new cultivation in the baldíos generated legal battles between the Mesta and the farmers, a struggle that was reflected in the fluctuating laws during the sixteenth and seventeenth centuries (Lynch, 1964).

Spains’s population growth resulted in increasing amounts of land being cultivated in the sixteenth century. This increasing demand was accompanied by an expansion of the food supply obtained through agricultural production by enlarging areas under cultivation rather than by raising agricultural productivity through intensive cultivation or through a qualitative transformation of the existing agrarian production forces, so that the agropastoral balance shifted in favour of cultivation. Montes areas underwent increasing damage caused by peasants, stockmen and city dwellers in search of fuel and timber. This tendency —expansion of arable lands to increase production at the expense of the pastoral sector— was the general trend during the next centuries, except in periods of population decline, such as in the sixteenth century.

An important technical innovation led to agrarian expansion: the gradual substitution of oxen for mules as the predominant draught animal. A mule could plough nearly twice as much land as an ox and this animal was more suitable in vineyards and orchards. However, mules usually ploughed shallower furrows and they needed a large amount of grain, which meant that a significant proportion of the land had to be oriented towards mule feed, whereas oxen could sustain themselves exclusively on the dehesas and other common pastures that were readily available. Also, to breed mules it was necessary to reserve pastures for horses, donkeys and mules were unproductive as meat for human consumption. As a consequence, mule husbandry required more monte and pastureland to be broken up to bring it under cultivation. Therefore, the use of mules probably unwittingly helped towards the rise in clearings and the conversion of grasslands and dehesas into arable lands.

In order to understand landscape transformation and land use change during the 16^th and 17^th centuries, it is necessary to emphasize one major economic factor. The royal economy was bankrupt so that the Crown and the municipalities had to devise alternatives to increase their incomes. One of them, with little success, was to sell enclosure privileges by denying access to the lands to any animals except those belonging to private owners. These newly-fenced areas were called a number of different names: cotos redondos, términos redondos, cerramientos, and also dehesa. However, soon after, the fencing system produced a strong resistance, and, in 1566, Philip II promised not to create any more enclosures (Vassberg, 1975).

Additionally, common rights were suffering aggressive attacks from usurpers. Individual landowners —not only nobles, but also peasants and ecclesiastics desirous of establishing full property rights— arrogated to themselves the right to declare their lands as being fenced and not subject to common rights such as the derrota de mieses. The baldíos were also appropriated by land users without any legal grounds for doing so.

Another element involved in the reduction in communal surface was the sale of baldíos. The Crown, from the last decades of the fifteenth century, had exploited this huge heritage. The baldíos had been initially sold, frequently to smallholders, to legalize lands that had been illegally ploughed, but, after a few years, the policymakers of the Royal treasury decided to adopt a more market-oriented attitude in an effort to increase its income (Calvo Poyato, 1990). Municipal lands were also sold by rural townships to buy up their obligations to their lords and to pay the increasing taxes required from the Crown.

Both the sale of baldíos and the enclosure movement (either by usurpation or authorized by municipalities and the Crown) reflected the expansion of individual ownership at the expense of the commons. These processes of selling the common heritage also led to an increase in the number and surface of large estates. Many dehesas had to be especially affected by this cultivation wave.

At that time, the dehesa still conserved its characteristic of being, in an ecological sense, exclusively pasture land, independently of its vegetation, which would be tree forested —in a more or less sparse fashion—, but also a shrubby or a completely afforested field.

Enlightenment and alienation

In Spain, the sixteenth century was characterized by a decline in population due to the joint action of disease epidemics, war consequences and socio-economic factors (Domínguez Ortiz, 1963). Agriculture decreased steadily, not only affected by the population crisis, but also because of the enormous impact of taxation on peasant agriculture, and the inflation rates. The result was a dramatic rural depopulation in large areas. A spontaneous recovery of forests occurred; it lasted until a demographic rise took place in the late seventeenth century, accompanied by a renewed clearing and cultivation of abandoned lands. From then on, the population steadily rose.

In the eighteenth century, agricultural production was stimulated by population growth, regulation changes and the rise in food prices, encouraging the growing of mainly grain crops, but also vineyards (Domínguez Ortiz, 1976; Herr, 1989). Sedentary livestock husbandry became comparatively more important than migrants; by the second half of the seventeenth century, the sedentary flocks numbered some nineteen million heads, whilst transhumance herds reached their peak, some three and a half million (Anes, 1994), despite the decline of the Mesta, which was finally abolished in 1836. At the same time, other regulations encouraged peasants to bring land under cultivation; as a consequence, many dehesas were more used as purely agricultural lands (Linares Luján and Zapata Blanco, 2003).

The mid-eighteenth-century Catastro of Ensenada, which was the first comprehensive statistical survey of the nation’s resources, drawn up between 1750 and 1760, showed that towns and cities possessed some dehesa boyal or dehesa del común (common dehesa), but also a number of private dehesas or montes adehesados. The rights affecting these private dehesas used to be complex because the ownership of the land and of the trees was very often different. For instance, in the city of Baza, in south-eastern Spain (not in the currently defined ecological dehesa area, but in a more semiarid location), there were three dehesas: the first was a privately-owned dehesa de pasto (a grazing deforested one); the other two were dehesas de monte (meaning afforested), with the acorns belonging to two separate owners and the pasture was common property of the local community (Cano García, 1990). Another example is the case of Hinojosa del Duque, a town situated precisely in the present dehesa area in Sierra Morena (south-western Spain). The survey records a large number of dehesas: the town possesses as propios one dehesa boyal, two dehesas with grass and acorns and another with grass, acorn and arable land; there was also one baldío covered by pasture, shrub land, oak woodland and arable land with the grass being the common property of the local inhabitants. The Duque of Béjar, a private landowner, had three dehesas with grass and acorn, and, finally, there were a number of quintos adehesados, a portion of land with a scattered layer of oaks (Torres Márquez, 1994); in short, a complex panorama that prevents us from coming to any sound conclusions.

According to the Dictionary of Authors of 1726, Diccionario de autoridades, at that time a dehesa was still a non-arable land oriented towards grazing. Although at this time a campaign against the commons had started, the enlightened reformists recognized the importance of reserved grazing areas. One of the most relevant politicians, Pablo de Olavide, although complaining in his official reports in 1768 of the large amount of vacant land in Spain due to extensive grazing, when promoting new settlements in deserted areas of Sierra Morena, in the south, established the reservation of a piece of land as a dehesa boyal for the common grazing of local draught animals (Perdices Blas, 1993).

The Enlightenment age meant, actually, the definitive expansion of cultivated lands. Almost the only way of increasing production was to place under cultivation the under-managed lands, especially pasture and forest land of comunes and propios. Some reforms affecting the distribution of commons and of church lands were formulated during the last decades of the eighteenth century in the context of a turbulent period, marked by European wars and invasion by Napoleonic troops. The impact upon the forest and pasturelands was dramatic: thousands of hectares of montes, baldíos and propios were broken up and brought into cultivation.

Although the sale of church lands had begun at the end of the seventeenth century, the definitive attack against the communitarian use of land and the conservation of baldíos anduncultivated land took place in the following century in the alienation period, based on the sale of public and church properties. The properties of the aristocracy were not affected, although the abolition of old rules such as seigniorial jurisdictionand the mayorazgo (whereby the properties could not be divided up) led to a great deal of land being placed on the market. Subsequently, as from the early years of the century, the municipal properties (propios) and other commons were forced to be distributed and sold. The purchasers were mainly middle class and wealthy landowners; in order to clear the forests for them to be turned into pasture lands, the new land-owners rented small pieces of land to peasants, who cleared the trees with the right to sow cereals during a number of years. This state-directed alienation process (desamortización) dramatically affected the communitarian land use system of many municipalities, involving a drastic rise in pasture and forest reclamation (Costa, 1898) (although to reduce the effects of this regulation on rural economy sparing the dehesas boyales from the sale was attempted).

The conversion of bush and forest ecosystems into cultivated land reached its maximum rate during the second half of the 19^th century. The intervention of the recently created Official Forestry Department played an important role in conserving part of this heritage, although millions of hectares of pasture and woodlands were cleared and turned into arable fields (Bauer, 1991).

Spanish agriculture underwent considerable changes when the common fields were fenced into holdings belonging to private owners, because the land started to be used more intensively (Kondo, 1990). Between 1800 and 1860, the area under cultivation in Spain increased greatly, from 8500000 to 13000000 ha (del Moral, 1979). In spite of this general review, it is difficult to draw any firm conclusions about the desamortización: in some places the result was an enlargement of the estates owned by the bourgeoisie, whereas in others there was a certain degree of fragmentation and distribution of land.

The lack of improvements in farming techniques prevented any increase in the productivity of grain per hectare. After some decades of expansion, in 1860 a period of crisis began which particularly affected wheat production. The marginal lands pressed into tillage during the earlier part of the century were relatively unproductive, and their yield could not compete with cheap foreign imports after 1882, so that these marginal lands were to be abandoned. Conversely, there was a great expansion of vineyards and olive groves during the second half of the nineteenth century because of a rise in exports (Zambrana, 1987; Guzmán Álvarez, 2004). From 1880 onwards, the vines suffered from phylloxera, with thousands of hectares all over Spain being abandoned. Some of these changes meant an intensification of land use and, therefore, many dehesas vanished, pushed out by the cultivated crops. But a great deal of these cultivated lands (it was previously either pasture land or woodland) was turned into monte a few decades later, when the crops and vines were in crisis; subsenquently, landowners, using labour, pruned and formed oak seedlings into a sparse framework of promising trees. Consequently, many of the present day dehesas (characterized by an even-aged tree layer) come from the period from 1870-1920, in that renewal and creation phase of new dehesas (we should point that the first certain use of the modern term dehesa for a savannah-like landscape was coined at this time, by the French writer De Lawrence in 1889 in Extremadura, Grove and Rackham, 2001).

To sum up, there was not a single result of the desamortización process in the nowdays defined as dehesa area, because, depending on the practices of the new owners, the dehesas were intensified and even replaced by arable lands, or could have been conserved through fencing and the prohibition of common use (Hernández, 1995). One important factor determined the future of most of these territories: the soil fertility was insufficient for maintaining a cereal or olive yield for very long, so that clearing a whole field of trees was not considered to be a good alternative.[2]

The park-like dehesa

As we have argued, the dehesa as a concept has changed throughout history. From its early times, dehesa meant a reserved land pasture often oriented towards local livestock grazing. Afterwards, as the importance of common rights declined and private ownership expanded,the significance of the term dehesa broadened and came to mean “a fenced land pasture”. This was still linked to the idea of reserved land not for free use; the difference was that private landholders took advantage of official sales and usurpations to configure their own dehesas by clearing the forests to convert them into grazing land.

In 1900, a dehesa was still described as a “monte de pasto, esté o no esté acotado”(Jordana and Morera, 1900). As we have explained, in Spanish the word monte means both “mountain” and “forest”, so this definition could be translated “as a forested pasture land, either fenced or not”. There is no vegetation in the definition, although in many regions there is an identification between the words ahuecar (to clear a woodland, conserving a dispersed tree layer) and adehesar (to make dehesa).

Nowadays, dehesa stillmeans a pastureland, which is usually fenced, as it appears in the Official Spanish Dictionary (Dictionary of the Royal Spanish Academy of Language, 2014). No trees are involved in this definition: the dehesa is not (yet) a botanical or an ecological concept. For many people living in rural areas, a dehesa is simply a pastureland (or, oftenly, it was a pastureland because it has been modified), and even in many cases a dehesa is just a place name on a map, in a plot which is presently cultivated or urbanised.

The difficulty in defining dehesa lies in the fact that it is a social, cultural and historical category. It’s a multi-meaning word (Lavado Contador et al., 2000) which specific definition depends on the approach being adopted. There are several dehesas: the shepherd’s dehesa and the ecologist’s dehesa, the dehesa of a farmer and the dehesa of a bird-watching tourist. There are forested and deforested ones, although, originally, the majority of dehesas probably had to be forested. Dehesas can contain different species of trees. It’s an agroecosystem, a pastureland, a landscape or a land use model. But for scholars and for administrative purposes, dehesa should be a concrete concept, should it not? The practice of science and the application of laws requires definition; however, working with words has to deal with the fact that vocabulary sometimes has a slippery role to play (Huntsinger et al., 2013).

Assuming that we need some clarity, let us be enlightened by our judges and lawyers, who need really precise concepts about which to argue. In the last decades there have been a number of definitions of dehesa in public regulations, each for a particular purpose. For instance, Law 1/1986 brought in by Extremadura (a region in the southwest of Spain), defines dehesa as a low-input pastureland of over 100 ha. The application of the agri-environmental scheme of the EU policy in Andalusia, in the south of Spain, defined it as an agrosilvopastoral system, usually derived from the clearing of a Mediterranean woodland, with a mainly purpose of stock-raising (Order of 6 April, 1999, Andalusian Regional Ministry of Agriculture).

A sound place to find a practical definition of dehesa may be scientific publications. The ecological concept of dehesa identifies it as an agroforestry system located in the south-western Iberian Peninsula characterised by the presence of a savannah-like open tree layer, mainly dominated by Mediterranean evergreen oaks (holm oak or Quercus ilex and cork oak or Q. suber) and, to a lesser extent, by the deciduous Q. pyrenaica and Q, faginea (Joffre and Rambal, 1993; San Miguel, 1994; Moreno and Pulido, 2009). It is characterised by a semi-arid Mediterranean climate, with annual rainfall ranging between 400 and 700 mm, dry, hot summers and cold, wet winters with a great variability between years. The soil usually consists of a thin, stony layer on top of the deep rock (schist and igneous rocks), which is easily erodible and poor in nutrients.

From this point of view, dehesa is characterised by: a) a particular physiognomy (a savannah-like or open park-like; b) a type of land use based on extensive (and game) livestock production; c) a basically two layered structure —trees and grass—; d) a particular geographical distribution. This dehesa narrowly coincides with the representation of the dehesa for the rural population of southwestern Spain because its pastureland can be described as a savannah-like landscape with an oak tree layer.

The change in its meaning has been favoured by the identification of the dehesa as a potentially well-adapted and economically viable multi-use agro-ecosystem suitable for promoting sustainable development in many farming areas of the Mediterranean basin. Therefore one of its historical meanings has gained a public relevance, mostly in academic and scientific works (Scarascia-Mugnozzaet al., 2000). For urban inhabitants, this dehesa has come to be the dehesa par excellence. Its balanced, park-like physiognomy might have contributed to this, fitting in perfectly with our widest aesthetic tastes. It would seem that an ecosystem in which grass, bush and tree species coexist and contribute to the feeding of livestock (sheep, cattle, pigs, goats and equines) and wildlife (including game species), and to the preservation of the environment in an extensive regime is not merely a sort of ecologist’s paradise but also the image of paradise for a great many humans.

A major key of this agroecosystem lies in its enclosed nutrient cycle. Compared to standardized Mediterranean agriculture, the flows of energy through the dehesa ecosystem are low, since dehesa outlets generally deflect only a minor part of the fluxes of the ecosystem towards themselves, whereas cropping systems change whole parts into crops (Naredo and Campos, 1980). Fertilizer and other energy surpluses are usually quite low. However, it should be realized that outputs are also scant.

The dehesa’s tree layer modifies environmental characteristics the same as in other savannah ecosystems (Scholes and Archer, 1997). The vegetation structure is made up of two main ecological components. The first is located outside the tree canopy and is composed of herbaceous plants; the second is composed of the oak tree and its associated herbaceous stratum. Tree canopy promotes a mosaic-like structure of herbaceous plant assemblages due to the shift in environmental conditions when comparing the situation under the tree and between trees (Puerto and Rico, 1988). Grass and crops take advantage of the shade provided during the hot periods; under the tree cover there is greater moisture and more organic elements in the soil from leaf shedding and animal excretion (Cerdá et al., 1988; Joffre and Rambal, 1993). As a result, there is twice as much potassium, phosphorus, nitrogen and carbon as in soils in the same field not under the trees, so that some ecological attributes like diversity and productivity tend to increase (Marañón, 1986).

The pastures are characterized by their low production. There is a production peak during the autumn and spring, accompanied by a sharp decline in summer and winter; during these periods, livestock has to be maintained with forage. Cereal crops are still produced in dehesas with suitable soil conditions; however, this is not a generalized practise. When grown, the cereals are usually grazed by the stock or harvested for animal feed during the drought period.

Canopy density is maintained at 10-60 trees ha^–1, with the optimum ranging between 50-60 trees ha^–1. Holm oaks (Quercus ilex) have various values as fodder crop, providing acorns and leafly branches, whilst cork oak (Quercus suber) main resource is cork. Mature trees are pruned regularly during the life of the oaks to remove selected branches, broaden their canopy cover and increase acorn production. Other wood products such as timber, charcoal and tannin used to be collected, although, at present, forest pursuits have been almost only reduced to natural cork.

A variety of grazing animals are reared in the dehesas, including sheep, goats, cattle, bulls, pigs and deers. Swine production is of special interest, because a particular breed of semi-feral pigs grazes acorns (Rodríguez-Estévez et al., 2012). Grazing exerts a powerful effect upon the flora and the system’s sustainability depends on carefully controlling it. When overgrazed or subgrazed, an inexorable shift towards inedible plants is likely to happen.

In the park-like dehesas are a number of endangered species such as Spanish lynx (Lynx pardina), black vulture (Aegypius monachus) and Spanish imperial eagle (Aquila adalberti), and several breeds of cattle, sheep, goats and pigs threatened with extinction have been conserved.

It has been pointed out that the dehesa shows a remarkable stability, biodiversity and sustained productivity (Bignal and Mc Cracken, 1996) as a result of its balanced two-tiered vegetation structure, incorporation of animal husbandry and botanically rich mosaic-like herbaceous plant layers. However, it has to be stressed that dehesa only maintains its equilibrium with sound human managing, keeping the woody and bushy vegetation under control, and relegating the shrubs to restricted areas.

In fact, when aplying this modern dehesa concept, centred on an ecological and landscape approach, there is the risk of forgetting that its conservation depends on a particular land use management and that its peculiar physiognomy is due to a specific ecological key factor: its extensive stock-raising use. We should remember that, whatever it is, it is not a natural ecosystem but rather an anthropogenic agro-ecosystem, a cultural man-made landscape (Silva Pérez, 2010). Therefore, the dehesa is in need of human actions in order to guarantee its continuation.