European Silver Fir Abies Alba Research Articles

Does fine scale spatiotemporal variation in seed rain translate into plant population structure?

In mast‐seeding species, strong annual variation in seed production is assumed to drive seed fate and ultimately plant recruitment. However, the effects of temporal variation in seed crops on spatial patterns of seed rain and recruitment are poorly understood, in part because of limited data on fine‐scale spatial variation of seed deposition. To investigate how mast‐seeding affects spatial variation in seed rain, we analysed a 15‐year data set on seed rain and population dynamics in a montane old‐growth forest (2 plots with 81 seed traps per ha), dominated by European beech Fagus sylvatica and, to a lesser degree, Norway spruce Picea abies and European silver fir Abies alba. Using geostatistical methods and point process modelling, we modeled 1) the relationship between annual seed crop and spatial heterogeneity of seed rain, 2) the temporal stability of seed rain hotspots and 3) the spatial relation of seed rain and recruitment into the population. The results illustrate the interaction between temporal and spatial variation in seed production and its consequences for population dynamics of mast‐seeding trees. The signature of annual variation in seed rain fades with seedling mortality over time in all three focal species. For beech, the cumulative probability of seed arrival over the whole study period drives spatial seedling and sapling dispersion patterns – mediated by light competition with older trees; seedling density was most strongly reduced by sapling density, while saplings were most frequently found in areas of low adult density. Such decoupling of spatial processes across life history stages, combined with spatial heterogeneity may play a larger role in driving stand‐level spatial dynamics than previously assumed.

Keystone role of Eurasian beaver Castor fiber in creating the suitable habitat over the core breeding range for forest specialist species the three-toed woodpecker Picoides tridactylus

The European breeding range of the three-toed woodpecker Picoides tridactylus overlaps with the distribution range of coniferous and mixed forests with domination of Norway spruce Picea abies or European silver fir Abies alba. The paper describes a new breeding site of the three-toed woodpecker in the Sobibór Forest, eastern Poland outside the distribution range of these two tree species and its relationship with Eurasian beaver Castor fiber. The birds occurred in dead alder forests and were recorded 3–4 years after forest started to decline due to the high level of surface waters associated with the keystone role of the beaver. The decaying cycle of trees was possible because the area settled by woodpeckers was protected as a nature reserve.

A battle of values: a case study of a blacklisted heritage tree represented by European silver fir Abies alba Mill. in a protected landscape in Norway

Old trees in protected landscapes may be historically important, but in some cases problematic if naturalising. In this study, we investigated how a blacklisted heritage tree is valued in a protected landscape, focusing on its cultural history, invasiveness and general management of the area. We used one European silver fir Abies alba Mill. planted in the 1890s as a case-study plant. A historical literary approach included the landscape history, cultural values and introduction history of A. alba. We accessed management information from management plans, botanical reports and the supervisory manager. The present spreading of A. alba was recorded with GPS along transects. In an area constituting approximately 13,600 m2, vegetation clearing and grazing have contributed to limit the invasion of A. alba. Most offspring (88%) were less than 15 cm tall and found within 30 m of the parent in half-shade positions. A. alba belongs to the area’s cultural historical identity, but has attracted more attention as a threat for plant species richness and habitats. Cultural and historical values are generally less prioritised in the management, which is, at present, mainly the responsibility of ecological conservationists. We therefore see a need for interdisciplinary collaboration to equally consider cultural and historical values.

Charakterystyka lasu grądowego z jodłą w rezerwacie „Jamno”

The “Jamno” nature reserve was established to protect the forest community with European silver fir Abies alba Mill. on the northern border of natural occurrence of this tree species in Poland. The results of current phytosociological studies (done in 2011) show that the oak-hornbeam forest – “Tilio-Carpinetum calamagrostietosum” association with “Abies alba”, exist within reserve. The present structure and species composition of studied community is determined by spontaneous changes of tree stand. The different proportion of silver fir in shrub and tree stand layers indicate the dynamic changes within this species population.

Improving the estimation of landscape scale seed dispersal by integrating seedling recruitment

Dispersal and recruitment play a critical role in determining the abundance and the spatial structure of regeneration. In this study, we estimated landscape scale seed dispersal using the inverse modeling method by fitting seedling counts to seed tree location and fertility in the European silver fir Abies alba Miller. Seed trees and seedlings from three age cohorts were counted in 30 plots on Mont Ventoux (southeastern France) at elevations from 995 to 1,605 m, where the following ecological variables were measured: elevation, slope, aspect, light availability, and tree density. We developed and fitted a dispersal model, including a new parameter, recruitment rate, which depended both on the ecological characteristics of the plots and on seed production. Elevation was the factor that affected seedling recruitment the most, with an optimum value at around 1,200 m. Estimated A. alba seed dispersal distances were short (median values for the three cohorts, respectively, 16.4–13.2–19.6 m). We demonstrated that including the ecological characteristics of plots and post-dispersal recruitment processes realistically reduced estimates of seed dispersal distances which are otherwise grossly over-estimated using inverse modeling procedures.

Ungulate browsing on European silver fir Abies alba: the role of occasions, food shortage and diet preferences

European silver fir Abies alba is the most heavily browsed conifer in Central European mountain forests. Attempts to reduce ungulate browsing have often been unsuccessful, controversial or too costly. The aim of the work described here was to improve our understanding of the factors that lead to browsing on silver fir. The silver fir content in the diet of three sympatric ungulate species, chamois Rupicapra rupicapra, red deer Cervus elaphus and roe deer Capreolus capreolus, was determined by microhistological analysis of faeces collected at four sites in the Alps. Further, the supply of silver fir was assessed at the individual tree and patch scale and then extrapolated to site scale. Silver fir consumption was highest in winter, when diet composition varied among sites but not among ungulate species. Towards the summer, site‐differences decreased and differences among ungulate species increased. Red and roe deer reduced consumption of silver fir, whereas chamois kept it constant. The use of silver fir was unrelated to the supply at the various sites, but increased with the proportion of trees growing amidst palatable herbaceous species. At the individual plant scale, ungulates browsed on the saplings with the larger needles. These results indicate that silver fir as food does not rank high among the available plant species, but is eaten opportunistically, especially when it grows close to more preferred food plants. However, when alternative food is scarce, particularly in winter, it may also represent a shortage food supply, and larger quantities are consumed. Yet, the fact that feeding on silver fir is mostly opportunistic may offer forest managers a way to approach the ‘browsing problem’.

Performance of the potentially invasive Siberian moth Dendrolimus superans sibiricus on coniferous species in Europe

Abstract1 The native range of the Siberian moth extends from the Pacific Ocean (Russian Far East, Japan and Northern Korea) across Siberia, Northern China and Mongolia to the Ural Mountains. At the beginning of the 21st Century, this species was documented west of the Ural Mountains in the Republic of Mari El, indicating range extension toward the west.2 The Siberian moth has recently been suggested for regulation as a quarantine pest for European and Mediterranean Plant Protection Organization member countries. However, no specific report on European host plants for this pest has been published so far.3 In the present study, larval host plant choice and performance was tested for the first time on coniferous tree species that are widely distributed and of commercial value in Europe.4 Based on dual‐choice tests on neonates and mortality, developmental duration and relative growth rates of the first‐ to sixth‐instar larvae, we found European larch Larix decidua to be the most suitable host for the moth larvae, whereas European black pine Pinus nigra and Scots pine Pinus sylvestris were the poorest hosts. The remaining conifer species tested, European silver fir Abies alba, Nordmann fir Abies nordmanniana, and Norway spruce Picea abies, were intermediate host plants. Douglas‐fir Pseudotsuga menziesii, originating from North America, was chosen by the larvae to the same extend as European larch, and was also highly suitable for larval development.5 If the moth is introduced to European countries, it will become damaging in stands of European larch and Douglas‐fir, mixed stands of fir and spruce; however, it will be less damaging in forests dominated by two‐needle pines.6 We predict that Dendrolimus superans sibiricus will be able to survive and develop on the main European coniferous tree species, including non‐native coniferous tree species, resulting in severe damage to large areas of forests.