Vegetation thumb|right|The summer drought is characteristic of the Madrid region's climate. (part of the transnational Ancient and Primeval Beech Forests of the Carpathians and Other Regions of Europe world heritage site) is a relict forest featuring a particular case of microclimate, allowing for Eurosiberian species that do not grow in the region in normal conditions. In the vicinity of the mountain peaks, oromediterranean vegetation such as Agrostis truncatula, ', Festuca indigesta, ', ', Minuartia recurva, Pilosella vahlii, Plantago holosteum and the Thymus praecox is common. Below the summit line, shrubby species such as the Cytisus oromediterraneus and the common juniper as well as the Scots pine take over. There are also masses of black pine and the pyrenean oak situated above the domain of the holm oak. thumb|left|Olive tree orchards in Arganda del Rey Eurosiberian flora is not common in the region, and species such as the moor birch and the silver birch are restricted to very specific humid valley areas with special climate conditions. The climax vegetation in the campiña is the holly oak. Some of the species that take over when the holly oak forest degrades are the "sticky shrub", the Retama sphaerocarpa, the French lavender, the Thymus mastichina and the Thymus zygis.
Vegetation thumb|right|The summer drought is characteristic of the Madrid regio.n's climate. (part of the transnational Ancient and Primeval Beech Forests of the Carpathians and Other Regions of Europe world heritage site) is a relict forest featuring a particular case of microclimate, allowing for Eurosiberian species that do not grow in the region in normal conditions. In the vicinity of the mountain peaks, oromediterranean vegetation such as Agrostis truncatula, ', Festuca indigesta, ', ' Minuartia recurva, Pilosella vahlii, Plantago holosteum and the Thymus praecox is common. Below the summit line, shrubby species such as the Cytisus oromediterraneus and the common juniper as well as the, Scots pine take over. There are also masses of black pine and the pyrenean oak situated above the domain of the holm oak. thumb|left|Olive tree orchards in Arganda del Rey Eurosiberian flora is not common in the region, and species such as the moor birch and the silver birch are restricted to very specific humid valley areas with special climate conditions The climax vegetation in the campiña is the holly oak. Some of the species that take over when the holly oak forest degrades are the "sticky shrub", the Retama sphaerocarpa, the French lavender, the Thymus mastichina and the Thymus zygis.