baumzaehlen - Primeval Forests & Their Trees

©2019copyright christoph hase

Boky National Nature Reserve, Slovakia


The reserve (1.8 km2) lies on a south to southwest facing steep dry slope at 280–590 m elevation 1.


The dominants in the upper canopy are Opens internal link in current windowQuercus petraea (sessile oak) and Opens internal link in current windowQuercus cerris (Turkey oak). Many small tree species grow under them; the most abundant ones include Opens internal link in current windowCarpinus betulus (European hornbeam), Opens internal link in current windowAcer campestre (field maple), Opens internal link in current windowCornus mas (Cornelian cherry) and Crataegus spp. (hawthorns). Forest is low on steep slopes but in the side valleys Quercus spp. become fairly large and less drought-resistant species also occur, e.g. Opens internal link in current windowFagus sylvatica (European beech) and Opens internal link in current windowAcer pseudoplatanus (sycamore maple). The tallest trees are slightly over 30 m. As the reserve is mostly too dry for F. sylvatica, tree species diversity is relatively high in the Central European context; some of the species (like Crataegus spp.) are not easy to tell apart.


This is an important reserve as very little almost untouched dry Quercus forest still remains in Europe. Some parts of the reserve have probably been used for grazing in the past, but for a long period there has been no human influence2. The oldest Quercus spp. are more than 300 years old 2. Annual precipitation is 720 mm and average annual temperature about 7.5°C 1.


A marked hiking trail leads through the reserve. In the valley below the reserve there is a highway which means much noise in the lower reserve.




1       Korpel’, Š. (1995): Die Urwälder der Westkarpaten. Gustav Fischer Verlag.


Quercus cerris (Turkey oak) dominated forest. Also Quercus petraea (sessile oak) with less coarsely furrowed bark and the branch, top left foreground. Acer campestre (field maple) sapling, bottom left.
Quercus cerris (Turkey oak, furrowed bark) - Carpinus betulus (European hornbeam) stand in side valley on almost even terrain. Also one Tilia × europaea (common linden, centre background). The second Q. cerris from the left is 30.4 m tall and has 234 cm girth.
Quercus cerris (Turkey oak, coarsely furrowed bark), Quercus petraea (sessile oak, less coarsely furrowed bark background), Carpinus betulus (European hornbeam, striped smooth bark).
Quercus cerris (Turkey oak) - Quercus petraea (sessile oak) forest on steep slope. Q. cerris with more coarsely furrowed bark.
Low Quercus cerris (Turkey oak) forest on dry steep slope.
Fagus sylvatica (European beech) stand in side valley. Also Tilia cordata (small-leaved linden, left with sprouts) and Quercus petraea (sessile oak, big tree centre background).
Forest in side valley. Acer campestre (field maple, foreground), Quercus cerris (Turkey oak, right), Quercus petraea (sessile oak, centre and behind Q. cerris). The small trees are mostly Carpinus betulus (European hornbeam) and Fagus sylvatica (European beech).
Bark of large Quercus cerris (Turkey oak).
Forest canopy. On the right Quercus cerris (Turkey oak) foliage.
Fraxinus excelsior (European ash, foreground centre to right), Torminalis clusii (syn. Sorbus torminalis, wild service tree, left centre with some yellow leaves), Acer campestre (field maple, behind the Torminalis). Behind them larger Quercus petraea (sessile oak) and Quercus cerris (Turkey oak).
Balancing rock "Čertova skala". Quercus cerris (Turkey oak, right foreground), leaves of Cornus mas (Cornelian cherry, bottom right).
Part of the reserve from below.
Some tree species of the reserve.