What the Montado is

The Montado is an agrosilvopastoral system explored at several levels – trees, bushes and herbs – according to the potential of each region.

The Montado is an agrosilvopastoral system explored at several levels – trees, bushes and herbs – according to the potential of each region.

On the tree level it can be made up of oaks like cork oak (Quercus suber), holm oak (Q. rotundifolia) and less frequently pyrene oak  (Q. pyrenaica) and portuguese oak (Q. faginea), in pure or mixed populations with variable densities. The ground cover is occupied by pastures used by cattle or is used for dry land crops on a rotation system. The natural pastures can be occupied by shrubs, in variable proportions.

Humans are an integral and fundamental part of this ecosystem. It was through our clearing action that the montados were created, ever since we started intervening on our natural surroundings. Human management is necessary, in a more or less intensive way, in order to maintain the montado. Without this intervention, the system evolves, naturally to form a dense forest, where people have more difficulty obtaining resources.

The way this process of transformation of the Mediterranean forest developed influenced the structure of the system as it presents today. Some older practices still persist, now without context, making more difficult the adaptation of the system to the new ways of agrarian production. Other ways emerged, some well adapted to the system, other causing more or less serious disturbances.

The montado is a system for using the soil developed on a physical background that involves climate, pedological and geomorphological factors with specific characteristics. It is why this ecosystem is restricted to such a limited area, when compared to other ecosystems in our planet.

The physical background represents the potential resources available to be transformed by the biological components of the system. First vegetation, then herbivores, then carnivores and finally humans, who take advantage of all of them and try to maximize the resources, in a sustainable way. When it comes to climate, the montado is embedded in the Mediterranean region that offers these particular conditions: hot dry summers that last at least three months, and winters that are, on the other hand, moist and tempered or cold. Rainfall presents a wide range withing the same year, and over the years, varying between 300 and 800 mm annually and more focused in some seasons than other (especially winter and spring). The values for rainfall and the timing of its occurrence influence, in a very significant way, the composition and quantity of the pastures and the availability of food for cattle.

At Mediterranean latitudes, (30º-40º) the effect of the moist winds coming from the west (the sea), during the winter, soothing the continental cold, alternates with the dry and hot winds of summer, associated with subtropical high pressures. During winter, the Mediterranean basin is also subject to winds coming from the North Atlantic. These cold and moist masses of air warm up when in contact with the Mediterranean Sea, forming low pressures. These, then, result in short periods of intense rainfall, causing easy erosion of the soil. During summer the Azores High moves north, while hot and dry winds move up from the Sahara seaside (Sirocco wind).

As for the geomorphological aspects, the montados occupy preferably flat lands or softly rolling hills. They can occupy more steep areas, but in that situation the risk of erosion of the soil is high, being recommended it stays covered with bushes, in a more natural structure.

Several abiotic factors act differently to create a large diversity of variants in the system. The inclines and running of nutrients to lower areas, the various levels of sun exposure, the various types and depths of soils, as well as the various densities of arboreal cover, combine with different interventions of humans over time, level of pressure of grazing, cycles of rupture and pressure of usage, to create an extreme diversity in the patterns of the montado. From this diversity results a mosaic of structurally and ecologically interdependent systems.

The biotic components of the montado are its vegetation, structured on three levels: pastures, shrubs and trees; the soil, the animal and the human components. The animal species that generally take advantage of the resources of the montado are sheep, goats, cows, pigs and a series of wild species, many of them with hunting value.

The plant cover in the Mediterranean region is dominated by evergreen trees and bushes. These are adapted to minimize water losses during the dry hot summer – with small and hard leaves, that offer a small surface to volume ratio. As for the herbs, their strategy is to lay dormant during the dry season, normally in the form of seed, and adopt various forms of underground nutrient reserves – bulbs and underground stalks.

Vegetation is a major component of the montado system. We split it into three layers, according to height from the soil, playing distinct ecological roles. The arboreal layer is made up of species like cork oak (Quercus suber), holm oak (Q. rotundifolia) and less frequently pyrene oak  (Q. pyrenaica) and portuguese oak (Q. faginea), in pure or mixed populations, with variable densities and heights above 2 meters. The arboreal layer has on average a rate of soil occupation around 60 tress per hectare, with a cover of 20 to 40%, but these values can vary from less dense montados to those that show a rate of cover of 100%.

The bush layer if formed by wooded species in more or less dense formations, branching from the soil in mainly spherical shapes. The number of species, at this level, increases markedly, but we can name among them the kermes oak (Q. coccifera), Lusitanian oak (Q. lusitanica), mastic (Pistacia lentiscus), myrtle (Myrtus communis), laurustinus (Viburnum timus), strawberry tree (Arbutus unedo), rosemary (Rosmarinus officinalis) , cistas (Cistus sp.) and lavender (Lavandula sp.), thyme (Thymus sp.), heather (Erica sp.), gorse (Genista sp.), broom (Retama sp.).

Finally the herb layer, closer to the soil, hardly grows over 40 centimeters. At this level the number of species grows dramatically, allowing an adaptation of pastures to the varying quantity and periods of rainfall every year. On the Montado, these levels of vegetation are run to obtain an open system that allows to take the most of sun exposure for production of high quality biomass for cattle.

The soils over which the montados are developed are generally poor, from Paleozoic materials (granites, gneiss, shales, quartzites, etc.) or derived from their erosion (sandstones). They are essentially acid and neutral, lacking in nutrients and with little organic matter. This coincidence with the poorest soils does not mean that you can’t develop montado in fertile and nutrient rich soils. However, soils like these were always used for other crops, irrigated or not, of more intensive profile. Without a relevant role in this type of system and even preventing intensive crops in smaller scale properties, trees where cut down, there.

In fact, the montado is a system especially adapted to less fertile soils, because it allows, where other farming was not viable, to obtain resources in a continuous way, sustaining, when well-managed, the fertility level of the soil.

Another notable characteristic of this system is that it is especially suited for a multifunctional or integral exploitation, in a way to better face constant variations in climate conditions, that affect pastures and cattle in a major way.

Taking advantage of the various layers of the landscape includes using the highly nutritious natural pastures, using tree foliage for the same end, and its fruit, that can be more or less nutritious and preferred by the species being herded. Another use of the lower layer is cereal crops, an activity that took on a role of maximum intensity during the wheat campaigns of the 1930’s and 40’s but that, following the times, has been interchangeable with pastoral usage depending on the needs of the montado and the existing social and economic setting.

The use made of the arboreal layer is highly dependent on the existing species, directing the system to subsystems with different profiles of production. The holm oak acorn is the most nutritious fruit, like by animals and even by people, and so its presence the use for animal production. When the cork oak is dominant, the scene changes as it’s the cork production takes the main role, since this product can achieve high market prices due to its unusual characteristics of elasticity, thermal and acoustic properties, and the variety of applications it allows. Animal and agricultural activities become then less important, especially pastures, since the acorn from this tree has a lesser nutritious value, is more bitter and has more irregular production than that of holm oak.

The bush layer is, normally managed by cattle or agricultural machinery, because it prevents cattle from reaching the pastures, reduces farmable areas, makes the access to the tree by men, for pruning or cork extraction, more difficult, worsens the quality of the cork and wood by making harder to develop a straight trunk, and is responsible for a faster spreading of both fire and diseases.

However, the bush layer has an important role reducing the high temperatures felt during summer at ground level, allowing therefore to form the conditions for the germination of the tree fruits, facilitating in this way the regeneration of the system. After the germination, the bushes still protect the young trees from the action of herds. This layer also has other uses, complementary to those in the montado, like beekeeping, production of medicinal herbs, wild fruits and game. So, and in spite of the bush areas being normaly considered as a degradation of the system, they are fundamental for the renewal of the Montado and for a more complete and sustainable use of the land resources.

The montado has also, due to its biological complexity, a high diversity of fauna and flora. It is a region of feeding and rest for many migrating birds and several species of bats. This biologic wealth is an indicator of the good adaptation of the system to the natural environment, and also of its resilience.

Currently, the montado occupies big extensions in Salamanca, Estremadura, High and Low Alentejo, Western Andalucía and, in a spottier form, Castille – La Mancha, Castille – Leon and Madrid. The combined area of these montados occupies between 2 and 2,5 million hectares, from which 75% are in Spanish territory and 25% in Portugal.