Cattle, sheep, goats and pigs do not use vegetation in the same way. Differences in dietary selection, grazing height and browsing ability directly influence grassland, scrub, tree regeneration and the wider landscape.
Choosing a livestock species in the dehesa is not simply a production decision. Each animal moves differently, selects different foods and exerts a particular type of pressure on the vegetation.
Cattle generally prefer taller grasses; sheep use shorter swards; goats have a strong ability to select and browse shrubs; and Iberian pigs can use grass, woodland fruit and other seasonal resources.
The LIFE ScrubsNet document “Livestock and scrub management for dehesa regeneration” explains that these differences favour the development of different plant communities and help shape different landscapes. It also notes that behaviour does not depend on species alone: breed, age, experience, nutritional needs and environmental conditions can all modify feeding preferences.
Cattle: generally less selective grazing
Cattle generally have a low capacity for dietary selection and browsing. They tend to use taller, less diverse herbaceous communities and cut vegetation at a greater height than sheep or goats.
This can be useful in areas where grass needs to be grazed without placing excessive pressure on woody vegetation. At low stocking rates, cattle may allow some shrubs and young trees to develop.
Not all breeds behave in the same way, however. The protocol highlights that native breeds such as Berrenda and Pajuna cattle show greater selective and browsing ability and are adapted to using scrub in rocky or mountainous terrain. Marismeña cattle are particularly adapted to saline scrub pastures.
Sheep: short swards and intermediate selectivity
Sheep have an intermediate capacity for selection and browsing. Their grazing behaviour enables them to use medium-height and short herbaceous communities containing a relatively high diversity of species.
Merino sheep have a limited tendency to browse and can encourage the development of short, high-quality herbaceous pasture known as majadales.
Other breeds may behave very differently. Grazalema Merino and Segureña sheep have a greater ability to browse and use shrub vegetation in mountainous areas. Churra Lebrijana sheep are particularly adapted to saline scrub pastures.
It is therefore not always sufficient to refer simply to “sheep”. Breed and previous grazing experience are important when anticipating their effect on the holding.
Goats: browsers by nature
Goats have a high capacity for selection and browsing. They can choose small shoots, leaves and specific parts of herbaceous and woody vegetation and can access rocky or difficult areas that may be less suitable for other livestock.
This makes them a useful tool for using or controlling certain scrub formations. At the same time, they require particularly careful management in areas intended for the regeneration of holm oaks, cork oaks and other woody species.
Goats can reach and consume young shoots, meaning that excessive or continuous pressure may compromise regeneration. The protocol also notes that high-yielding dairy breeds generally have a lower browsing capacity than some native meat breeds.
Pigs: more than acorn consumption
Commercial white pig breeds generally have a limited capacity for grazing. Iberian pigs, by contrast, are particularly well adapted to the resources of the dehesa.
They can consume grass, browse and woodland fruit. During the montanera season, their activity is concentrated mainly on acorns and herbaceous vegetation.
Their ability to use seasonal resources makes Iberian pigs a characteristic part of the system. As with any livestock species, however, their presence should be incorporated into a management calendar adapted to food availability and the sensitivity of each area.
Breed and management also matter
Differences between species provide general guidance, but they cannot predict all livestock behaviour.
Breeds within the same species may have very different browsing abilities. Age, learning, previous experience, herd composition and the availability of alternative foods also play an important role.
An animal accustomed to using scrub may behave differently from one that has never encountered it. Similarly, a shortage of grass can increase the consumption of woody species that would normally receive less attention.
Good management therefore requires observation of both the animals and the vegetation rather than reliance on a general classification alone.
Combining species to make better use of resources
These differences can also be used in a complementary way through mixed or sequential grazing.
For sequential grazing, the protocol suggests that cattle may enter first because they consume taller grass and are generally less selective. Sheep or goats can then follow, using vegetation closer to ground level and selecting small woody shoots.
This combination may improve resource use on large holdings or in paddocks with abundant scrub. Each species uses different areas and selects different foods, contributing to more complete use of the available vegetation.
Combining species does not, however, mean increasing stocking rates without control. Animal numbers, the order of entry, occupation periods and recovery times must all be adjusted carefully.
Choosing livestock according to the objective
No single species is suitable for every area or management objective.
Where the aim is to encourage woody vegetation, livestock species or breeds with limited browsing behaviour may be used at low stocking rates. Where the objective is to make use of a scrub formation, animals with greater selection and browsing abilities may be more appropriate.
Additional precautions will be required in regeneration plots, particularly with animals capable of reaching young shoots. In other areas, the same behaviour can be used to control scrub or diversify livestock diets.
Decisions should reflect the vegetation type, topography, season, forage availability and the productive and environmental objectives established for each paddock.
Understanding how each animal feeds
Livestock are not external to the dehesa. Their behaviour helps determine which plants thrive, which decline and what structure the landscape develops.
The LIFE ScrubsNet message is clear: managing the dehesa means understanding how each species and breed feeds.
Cattle, sheep, goats and pigs can perform complementary functions, but their effect will depend on stocking rates, seasonal timing, rotation and recovery periods. Understanding these differences helps turn grazing into a tool for balancing production, conservation and regeneration.
The LIFE ScrubsNet project is co-funded by the European Union through the LIFE programme, LIFE20 NAT/ES/000978.