The European beech (Fagus sylvatica), or just beech for short, is an incredibly successful tree species. As the "mother of the forest", it is today the dominant tree species in natural forests in many parts of Central Europe. Prerequisite for its thriving is a mild climate with sufficient rainfall.
The beech creates good soil conditions with its rich fall of leaves and its intense root penetration also of deeper soil layers. It is a true master at the art of living. The beech can prospers on nutrient-poor sand dunes and acid rock just as well as on nutrient-rich soils like loamy ground or limestone soils. Without human interference, beech forests would cover around two thirds of Germany's land area.
The beech is highly competitive: Its canopy grows so dense that only very little light can reach the forest floor, hence no diverse herbal and shrub layer is able to develop. The small quantity of light however is sufficient for beechlings and young plants to grow, enabling the beech to dominate over other tree species that require more light.
How beech forests managed to populate large parts of Europe after the last Ice Age is an ecological process that is unique in the world – and, as far as man allows it – this process is still going on.
A natural beech forest is by no means limited in the number of species living in it. The biodiversity in beech forests is estimated to be around 10,000 species, 6,000 of which are animal species! Many plants, fungi and animals, for example Bechstein's bat and spotted woodpecker, find their habit first and foremost in hollows, cracks and knotholes of the old beeches and in the deadwood of decayed trees.
In spring, the light can still reach the forest floor unhindered and the herbal layer is able to develop. The early bloomers have their blooming period from March to May. Millions of spring snowflakes are growing here, best to be seen along the Naturpfad Thiemsburg and in the Brunstal. Wild garlic is abundant with a blanket coverage of more than 10 km2.
In summer, go for a walk on the Steinbergweg to see the inhabitants of the open landscape at their best. Most orchid species are in flower in the first half of June. Of the currently identified 26 orchid species in the national park, 16 can be found in the forest.
In autumn, deciduous trees lose their leaves. But before they do so, they extract important substances and store them until next spring. Chlorophyll is the first colouring to be extracted, and the leaves turn yellow by carotinoids. Some species synthetisise anthocyans, which causes a red colouration of the leaves.
Winter is a time of rest. Only few plants species in the herbal layer keep their leaves in winter and can do photosynthesis on frost-free days. During longer frost-free periods, you might spot the odd earlywood anemone. Sufficient warmth to revive the herbal layer, however, only comes with the sun in March.
Beeches reveal how vegetation in Europe developed after the last Ice Age, since their reforestation phase is still going on. The growth process of natural forests that are left to their own devices we can also see how their adapt to global climate change.