Forest migration northward. Though "Fagus" and "Picea" populations did not expand directionally, they have grown in the Scandinavian range. The movement of "Picea" species in the past 1000 years has shown a strong connection to climate change through a model comparison. In the more recent past, there has been documentation of elevation shifts in distribution of many core forest tree species of Catalonia. The populations of two tree species (European Beech, "Fagus sylvatica"; and Holm Oak, "Quercus ilex") were evaluated in their dynamics over elevations through time. Generally, Holm Oak reside lower on mountain slopes than does European Beech. In the past
Fagus sylvatica depends on the location: in forest areas, "F. sylvatica" grows to over , with branches being high up on the trunk. In open locations, it will become much shorter (typically ) and more massive. The leaves are alternate, simple, and entire or with a slightly crenate margin, 5–10 cm long and 3–7 cm broad, with 6–7 veins on each side of the leaf (7–10 veins in "Fagus orientalis"). When crenate, there is one point at each vein tip, never any points between the veins. The buds are long and slender, long and thick, but thicker (to ) where the buds