T1E1 Quercus-Fraxinus-Carpinus betulus forest on eutrophic and mesotrophic soils

Description

Basophilous deciduous species-rich forests in temperate lowlands and midlands whose climate, by any combination of frequent input by rains and modest water loss through scarce direct sunshine, lacks any Mediterranean nuance, enabling the development of deep, humid but aerated, well-developed eutrophic soils.

Protection

In Spain, despite a certain mismatch in its definition, most of these forests have been traditionally considered protected by the EU Habitat Directive through their assimilation to code 9160 ("Sub-Atlantic and medio-European oak or oak-hornbeam forests of the Carpinion betuli"). Variants in steep, rocky and shady slopes (see below) may on their part be taken as protected with priority under 9180* ("Tilio-Acerion forests of slopes, screes and ravines").

Phytosociology i

• Carici pendulae-Fraxinetum excelsioris
• Crataego laevigatae-Quercetum roboris
• Euphorbio hybernae-Fraxinetum excelsioris
• Festuco giganteae-Fraxinetum excelsioris
• Fraxino angustifoliae-Ulmetum glabrae
• Helictotricho cantabrici-Tilietum platyphylli
• Helleboro occidentalis-Tilietum cordatae
• Hyperico androsaemi-Coryletum avellanae
• Hyperico androsaemi-Quercetum roboris
• Hyperico androsaemi-Ulmetum glabrae
• Laserpitio eliasii-Coryletum avellanae
• Luzulo henriquesii-Aceretum pseudoplatani
• Omphalodo nitidae-Coryletum avellanae
• Polysticho setiferi-Fraxinetum excelsioris
• Pulmonario longifoliae-Quercetum pyrenaicae
• Saxifrago hirsutae-Coryletum avellanae
• Smilaco asperae-Coryletum avellanae
• Valeriano pyrenaicae-Fraxinetum excelsioris

Relations with other habitat types

A mostly basophilous, more eutrophic analogue of T1Bx, functioning as the zonal forest in the north of the ecoregion, either below T172 beechwwods (with Quercus robur as the dominant oak in mature stands) or, when in montane areas, replacing them in sunnier slopes, with Quercus peatraea as the dominant oak. In acidic areas it takes the place of, or intermixes with, said T1Bx in colluvia or valley sides, whose soils are deepened and enriched by materials eroded from upper-lying areas. It may even act as a riverine formation, instead of T111 and T121, in modest watercourses with negligible floodplain and almost dry in summer. In the coast, transitions towards T22x are widespread. It is also successionally and spatially very close to S371, with a vast shared floristic background. In narrow valleys and gorges, including steep foothills where coarse colluvia are deposited, lime trees may gain abundance, suggesting the convenience of admitting EUNIS T1F ("Ravine forest"), whose regional representative would be T1F4 ("Pyreneo-Cantabrian mixed Ulmus-Quercus forests"). However, the distinction between blocks T1E and T1F, at least on floristic grounds, is shaky, as shown by the very name (let alone the respective descriptions) of the level V regional EUNIS within T1E1: T1E19 ("Pyreneo-Cantabrian Quercus-Fraxinus forests"). Therefore, at least for the time being and at level IV, all these eutrophic mixed forests of the ecoregion, regardless of their topographic position, are joined together.