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The aim of the study was to determine whether extracts of tobacco leaves may reduce feeding of the large pine weevils on twigs of pine – Pinus sylvestris. The research was conducted in laboratory conditions. The research proved statistically significant decrease in damage size on the pine twigs as a result of application of each tested extract.
In the years 2005– 2006, in the Karkonoski National Park there were conducted observations on infestation of spruce trees by bark beetles (Col., Curculionidae, Scolytinae). Data on bark beetle species composition and frequency of occurrence of individual species were collected. The data on development phenology of the small spruce bark beetle Ips amitinus in the upper subalpine spruce forest sites (1000– 1250 m a.s.l.) indicated higher frequency of occurrence of this species (26.3%) when compared to the European spruce bark beetle Ips typographus. The study included analyses of population size, density, fecundity and mortality of I. amitinus. The rate of development in I. amitinus in the Karkonosze Mts. is similar to that observed in the Alps. The number of laid eggs observed was low and the reproduction success was very high at minimal mortality. Establishment of feeding galleries and egg laying lasted several weeks and 1/3 of feeding galleries were found in the second series of trap trees.
The aim of the study was to verify whether methanolic extracts prepared from plants of 26 selected species contained substances reducing feeding of Hylobius abietis beetles on shoots of Pinus sylvestris. Experiments were conduced under laboratory conditions. A statistically significant reduction in the size of damage was recorded on pine twigs treated with methanol extracts of leaves of Trifolium repens, Lupinus polyphyllus, Robinia pseudoacacia, Tanacetum vulgare, Nicotiana tabacum, Sambucus nigra, Convallaria majalis and Lycopersicon esculentum. Probably the strongest antifeedants were methanolic extracts of leaves of Lupinus polyphyllus, Robinia pseudoacacia and Convallaria majalis.
The purpose of the research was the comparison of capturing effectiveness of large pine weevils with different types of traps. The research was conducted in the forest of Oborniki forest division (RDLP Poznań). It has been shown that most large pine weevils are captured by the IBL4 type trap. The least effective trap turned out to be the trap log.
The paper presents an evaluation of health condition of selected oak stands in the Włoszakowice Forest Division based on a synthetic tree damage index. Field work was conducted in 2007-2008. In order to perform this task seven experimental sites were established, with 25 trees from Kraft’s age classes I-III evaluated in each. It was found that the overall health condition of most stands deteriorated in 2008 in comparison to 2007.
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