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The primary aim of using treeshelters is offering protection for young trees against browsing and fraying. However treeshelters also significantly modify growth of protected trees. Even though there are many investigations on the behavior of broadleaved tree species in treeshelters, conifer species and particularly Douglas-fir [Pseudotsuga menziesii (MIRB.) FRANCO] have not been subject yet to comprehensive studies with different types of treeshelters. This is even more surprising as largescale damage caused by storms as well as devastations caused by climate change (and subsequent conversion) may most probably lead to further rising use of treeshelters and also more planting activities of Douglas-fir. Additionally silvicultural measures for compensating an expected short-coming of conifer timber from highly productive species on the roundwood marked together with an unbalanced situation of deer stock and natural regeneration may further intensify such trends. Thus, the aim of the study was to analyse growth and mortality of Douglas- fir in three different types of treeshelters including one control without protection considering two site categories of water supply (above-/below average paired sites), additional fencing (yes/no, for trees without treeshelter) and weeding/tending measures conducted every year (yes/no). The experimental design is distributed across 10 locations on public forest estates within southwest Germany/State of Baden-Württemberg. Monitoring took place over three vegetation periods (2012-2014) on three year old plants, planted bare-rooted. Growth of height (H) and stem diameter (at branch collar, WHD), measures of stability (H/WHD-ratio) as well as cumulative mortality have been recorded and compared across types of treeshelters and combined effects of water supply, fencing and mechanical weeding/tending using tests on mean values in mixed models. There were significant effects of the type of treeshelters on growth and mortality along the three years. Starting at the same size seedlings grown in sheltertype Ventex repectively Plantagard-shelter and Plantagard-mesh, when comparing to seedlings grown without protection, had a mean tree height higher by 27.4 cm respectively 18.2 cm and 13.7 cm (sign.), a mean WHD thinner by 1.5 mm, respectively 3.0 mm and 1.2 mm (partly sign.) and a higher mean H/WHD-ratio by 26 respectively 31 and 15 (sign.). The cumulative mortality was lower with a value of 12.7% respectively 15.8% and 18.1% in comparison to trees without protection (28.2%, sign.). Despite of several significant differences in height and diameter growth, measures of stability and mortality when compared to seedlings without protection, differences range still within values of trees grown up without protection as known from literature. Unprotected and planted Douglas-fir trees exhibit height development fast enough to overgrow shelters of a height of 90 cm after 2 years. Mean H/WHD-ratio of Douglas-fir three years after plantation represents sufficient stability, nevertheless it reaches published values from trees under long-term experiments of canopy closure. When analysing effects of treatments jointly with specific combinations of water supply, fencing and mechanical weeding/tending only rarely large differences in growth and mortality were found compared to seedlings grown in different sheltertypes. Additionally, when considering full costs of tree shelters as well as the potential to improve local game management, we do not recommend the use of tree shelters in the case of Douglas-fir. [ABSTRACT FROM AUTHOR]

In Central Europe, ancient woodland sites with a long ecological continuity are regarded as especially valuable habitats and often stand out as biodiversity hotspots. This is particularly true for deciduous forests with overmature oak (Quercus robur, Q. petraea) and beech (Fagus sylvatica) trees, which are frequently parts of protected areas. But even before the term ecological continuity was introduced and the importance of overmature trees for biodiversity was widely recognized, there have been early 19th century approaches to protect veteran trees and deciduous woodland for aesthetical and historical reasons. With regard to forest birds and bats, already around 1800 utilitarian conservation efforts were made to protect species that were known to be natural enemies of arthropod pests. Already in those days forest scientists called for the preservation of old hollow trees for the purpose of protecting insectivorous birds and bats. Such trees became later known as habitat trees. The question arises, whether these early nature conservation ideas have been received or implemented by forest managers at that time. We therefore conducted a systematic review of the 19th century volumes (1825-1900) of the oldest continuously published scientific forestry journal worldwide, the Allgemeine Forstund Jagdzeitung (AFJZ). By evaluating 75 years of journal and forestry history, this study aimed at analyzing and discussing to what extent ideas and measures supporting ecological continuity and nature conservation were implemented in 19th century forest management. By reviewing the 19th century AFJZ volumes, it could be shown that the central topics appreciation and protection of veteran trees, and the protection of habitat trees and birds were regularly discussed. Both the temporal emphasis and the practical implementation of the different topics, however, varied considerably. While contributions dealing with veteran trees and their protection were most notably published between the 1820s and the 1850s, bird protection was a hot topic between the 1850s and the mid-1870s. The concept of habitat trees was occasionally mentioned between 1855 and 1900. Although systematic inventories of veteran trees were compiled in several Germans states and some trees were protected, general legal instructions for veteran tree protection were not enacted in the 19th century. The same is also true for the concept of habitat tree protection, which was known to foresters from journals and books already in the second half of the 19th century. Despite sporadic conservation efforts, rationalized forest management resulted in extensive losses of over-mature trees and, thereby, in a widespread disruption of ecological continuity. In Germany, however, the first systematic conservation network of forest nature reserves and natural monuments was established in Prussia from 1906 onwards. When looking at the perceived history of bird protection, the situation appears to be different. The legal protection of useful birds, which was primarily seen as an economic issue, was heavily lobbied by influential forest scientists. Their political efforts were directed towards both national and international bird protection. After the successful implementation of national legislation on bird protection in the 1880s, interest in the protection of birds faded among forest scientists. New nature conservation ideas, which went beyond utilitarian reasons for protecting birds, were more common among other middle- class intellectuals than among foresters. The loss of bird habitats due to forest management intensification, however, continued during the whole 19th century. [ABSTRACT FROM AUTHOR]