165 Silva Gabreta vol. 16 (3) p. 165–186 Vimperk, 2010 The development of tree species composition in the Rachel–Lusen region of the Bavarian Forest National Park Marco Heurich * & Karl Heinz Englmaier Nationalpark Bayerischer Wald, Freyunger Straße 2, D-94481 Grafenau, Germany * marco.heurich@npv-bw.bayern.de Abstract About 4,500 years ago, at a time when the human influence on the landscape was still negligible, the silver fir (Abies alba) spread over the area of the Bohemian Forest mountain range. While the proportion of Euro- pean beech (Fagus sylvatica) remained relatively stable, Norway spruce (Picea abies) was gradually displaced and beech-fir forests became predominant. Other tree species played a much less significant role. Over the centuries, there was a growing human influence on the composition of the forest. By the 16 th cen- tury, glass manufacturing had become an important industry. It required firewood to run the furnaces and potash to reduce the melting point of quartz. Selective cutting was the practised method of forest use. By the end of this period, Norway spruce had become the most common tree species, followed by Euro- pean beech and silver fir. The age of planned forestry began in the first half of the 19 th century when owner- ship of the forests in the National Park area was transferred to the Kingdom of Bavaria. At first, forestry practices were based on shelterwood cutting (until 1880) and later, on the Bavarian “femelschlag” technique (expanding gap management). As a result of these types of forest management, the proportion of spruce in relation to silver fir increased even further, while the European beech component remained constant. This development continued in the 20 th century. The introduction of the principle of land rent theory led to an intensification of forestry practices. As a consequence of World War I and II, the tree harvest reached a peak level. At the time of the establishment of the Bavarian Forest National Park in 1970, the proportion of spruce had increased to 72%, silver fir had decreased to only 3.2%, and European beech was still very stable at about 25%. During the first 20 years after establishment of the Bavarian Forest National Park, the tree composition changed only very little, while the tendency for spruce to increase and silver fir to decrease continued. A break in this longstanding trend did not occur until 1992–2002. Due to a spruce bark beetle infestation, the proportion of spruce decreased, while that of silver fir increased – in absolute numbers as well – for the first time. The proportion of other tree species also increased. In the meantime, mountain ash has become the third common species. Key words: silver fir, European beech, Norway spruce, Moutain ash, forest history, forest ecology, Bavarian Forest National Park, Bohemian Forest INTRODUCTION The main goal of national parks is the protection of natural processes that are not influenced by human activity. This is known as “ecological process management”, and means that eco- logical processes, such as nutrient cycles, disturbance, natural succession, decay, competi- tion, predation, symbiosis, birth, and death are allowed to take place without human inter- vention. The formula “leave nature to itself” was characterised as the goal of environmental protection in national parks. An additional purpose also designated by the IUCN as a prior- ity goal of national parks is the preservation of biodiversity and, consequently, species pro- tection (IUCN 1994).