Health condition of Norway spruce Picea abies (L.) Karst. stands in the Beskid Mts

The health condition of spruce stands in the Moravian-Silesian Beskids is affected by several predisposition factors, the most important of which is the allochthonous character of spruce grown on improper sites. When exposed to a low supply of nutrients and intensive mechanical damage mainly by game, the trees are susceptible to rot infestations, climatic agents and mechanical destruction by snow, hard rime and wind. At present, air pollution does not show any significant impact on the spruce stands; it rather acts as a less important predisposition factor on mountain peaks. The physiological condition of trees is not impaired to the extent which would facilitate infestation with phytophagous or cambioxylophagous insects

Comparison of the pheromone dispensers ID Ecolure, Pheagr IDU and Duplodor for the double spined bark beetle [Ips duplicatus]

In 2000 and 2008, the effects of Duplodor pheromone lures in two variants (10 of each) with ID Ecolure (Poland) and ID Ecolure with Pheagr IDU (Czech Republic) used against Ips duplicatus were compared. IBL−3 and Theysohn barrier traps were installed in lines. In both cases, the total number of beetles captured during the entire season or beetles of the hibernating and summer generations were always significantly higher when using the ID Ecolure pheromone lure. The first beetles appeared at the end of April and the last ones in September. Flight activity culminated at either the end of April or beginning of May as well as at the end of June in both years, which reflects the two generations of beetles per year

Pheromone trapping of the double-spined bark beetle Ips duplicatus (Coleoptera: Curculionidae, Scolytinae): seasonal variation in abundance

Ips duplicatus adults were sampled with pheromone-baited black window-slot traps (Theysohn) in 70- to 100-yearold Norway spruce (Picea abies) stands between 280 and 650 m a.s.l. in the eastern Czech Republic and southern Poland during 2000– 2010. Sets of 5–12 traps were placed about 20 m from the edge of the infested forest. Each trap was baited with a standard synthetic pheromone lure (ID Ecolure), and was setup 1.5–2.0 m above the ground. The objectives were to determine the relationship between the numbers of adults trapped in the overwintered generation and those in the offspring generation. According to data from 135 traps, the numbers of overwintered beetles captured in spring (April–June) were significantly higher than the numbers captured in summer (July–August), but the numbers of offspring beetles captured in summer were significantly correlated with the numbers overwintered beetles captured in spring. The spring captures can be used to estimate the threat caused by I. duplicatus during the whole vegetation season. The traps installed in summer should be used to determine the peaks in the bark beetle flight activity, thus enabling early identification of trees infested by I. duplicatus, especially inside stands

A bark beetle infestation predictive model based on satellite data in the frame of decision support system TANABBO

The European spruce bark beetle Ips typographus L. causes significant economic losses in managed coniferous forests in Central and Northern Europe. New infestations either occur in previously undisturbed forest stands (i.e., spot initiation) or depend on proximity to previous years’ infestations (i.e., spot spreading). Early identification of newly infested trees over the forested landscape limits the effective control measures. Accurate forecasting of the spread of bark beetle infestation is crucial to plan efficient sanitation felling of infested trees and prevent further propagation of beetle-induced tree mortality. We created a predictive model of subsequent year spot initiation and spot spreading within the TANABBO decision support system. The algorithm combines open-access Landsat-based vegetation change time-series data, a digital terrain model, and forest stand characteristics. We validated predicted susceptibility to bark beetle attack (separately for spot initiation and spot spreading) against beetle infestations in managed forests in the Bohemian Forest in the Czech Republic (Central Europe) in yearly time steps from 2007 to 2010. The predictive models of susceptibility to bark beetle attack had a high degree of reliability (area under the ROC curve - AUC: 0.75-0.82). We conclude that spot initiation and spot spreading prediction modules included within the TANABBO model have the potential to help forest managers to plan sanitation felling in managed forests under pressure of bark beetle outbreak.peerReviewe

Management of semi-natural grasslands benefiting both plant and insect diversity: The importance of heterogeneity and tradition

Biodiversity of semi-natural grasslands depends on the management practices used. However, management systems suitable for one taxon, such as plants, can be detrimental to other taxa, such as insects, and vice versa. This study attempts to support conservation management planning by clarifying the effects of different grassland management practices on species richness and species composition of vascular plants, butterflies, moths, orthopterans and ground beetles, also taking into account the effects of climate and the landscape context. The study was performed in the White Carpathians Protected Landcape Area and UNESCO Biosphere Reserve (Czech Republic), which is famous for its grasslands with the globally highest fine-scale plant species richness. Different management practices (mowing, grazing, abandonment and mixed management; the latter including the previous three) were applied for at least five consecutive years at 34 sites, where plants and different insect groups were subsequently sampled. Effects of management on species richness of different taxonomic groups were assessed using generalised linear models, whereas the effects on species composition were assessed using redundancy analysis. Management influenced plant, butterfly and moth species richness, but the effects of particular management practices on all species and species of regional conservation importance differed between these taxonomic groups. Plant and moth species richness increased with mowing, but moth species richness decreased with grazing. Mixed management favoured plant and butterfly richness. Plant species composition was infuenced by mowing, grazing and mixed management while that of moths by mowing and grazing. Orthopterans and ground beetles did not respond significantly to management. Our results indicate that conservation management should comprise the traditional practices that have historically contributed to the formation of the biological diversity of the semi-natural grasslands in the study area. In particular, grazing may not be optimal for traditional hay-meadows and mowing should be carried out similarly as in pre-intensive farmland, creating spatio-temporal heterogeneity rather than uniformly cutting large grassland areas during a short period. In general, the optimal management should be heterogeneous, applying different practices in a mosaic or at different times during the season