The natural regeneration of beech stands is influenced by several factors. However, the most important is the canopy, i.e. the mutual contact and interweaving of the crowns of the renewed vegetation and the associated lighting conditions. Equally important are the soil conditions and the amount of dead wood. The optimal conditions for the emergence of a new generation of beeches were investigated by scientists from the Faculty of Forestry and Wood Sciences under the leadership of Ing. Bílek.
The area on which the research took place lies in the Voděradské Bučiny National Nature Reserve. The reserve was established in the 50s of the last century and there are remnants of natural beech stands. European beech (Fagus sylvatica) is the most widespread deciduous tree in the Czech Republic. In the past, however, its representation was up to five times greater. The study itself was performed on two permanent experimental plots of 1 ha, which included other smaller plots representing conditions under a fully involved mother stand. The most important factor by which the areas differed were the size of the clearings, which positively or negatively affected them.
The characteristics of rejuvenation, ground vegetation, dead wood, natural regeneration density in different height classes and the properties of dominant beeches in natural regeneration were related to soil moisture and light conditions. Light is a very important factor for plant growth, so the light characteristics were derived from hemispherical photographs, which are created using a special wide-angle lens called a fisheye, which can display an angle of up to 180 °. Beech is a tree quite tolerant of shade, but the results showed that the greatest coverage and density of seedlings is found in small clearings. On the contrary, the lowest density of seedlings was under the closed vegetation, where the light conditions for the survival and growth of seedlings are insufficient. In larger clearings, the biggest obstacle for the successful restoration was a competition with herbaceous vegetation, especially the wood small reed (Calamagrostis epigejos). At the northern edge of the large clearings was found the highest level of direct sunlight, the lowest soil moisture, and thus worse overall conditions for the growth of beech rejuvenation.
The practical output of the study is a recommendation for forestry practice. During small-scale restoration, it should respect the established laws, i.e. produce relatively small clearings, where optimal lighting conditions and a low level of competition of ground vegetation are guaranteed. Their further expansion during logging should not proceed north.
Ing. Lukáš Bílek, Ph.D. (* 1978)
He studied forestry at the Faculty of Forestry and Wood Sciences, CULS in Prague. He received his doctorate in forestry in 2009 and has been working as a teacher since then.
Prepared by: Michaela Veselá