Nonalluvial Atlantic, sub-Atlantic and nemoral forests dominated by Fraxinus excelsior, particularly characteristic of Britain, of the northwestern Iberian peninsula and of the Baltic moraine hills of Mecklenburg, but distributed also in other parts of central and southeast Europe. Pioneer secondary formations on abandoned cultivated land are included.
Fraxinus excelsior-dominated facies of calciphile oak-ash forests (unit G1.A173), characteristic of the French Paris basin, particularly on chalk deposits; their affinities are with the southeastern British formations of unit G1.A21.