Search

Inonotus obliquus, a wood-decaying mushroom, has been used as a health-promoting supplement and nutraceutical for centuries. It is a source of bioactive compounds accumulated in both the conks (pseudosclerotia/sclerotia) and the biomass obtained in vitro. This study aimed to qualitatively and quantitatively analyze the bioelements and selected metabolites produced in mycelial cultures obtained from different host species. The mycochemical potential of mycelial cultures isolated from pseudosclerotia grown in Betula pendula, Alnus glutinosa, and Carpinus betulus was compared. Parent cultures were obtained in two types of medium (malt extract agar substrates without and with birch wood). Experimental cultures were developed in 2 L bioreactors for 10 days. The content of bioelements was determined using FAAS and FAES methods. Organic compounds were estimated using the RP–HPLC–DAD method. The cytotoxicity of the extracts was evaluated in human keratinocytes HaCaT, human skin fibroblasts BJ, human liver cancer HepG2, human melanoma A375, and mouse melanoma B16-F10. The extracts showed the presence of bioelements: sodium, potassium, magnesium, calcium, zinc, manganese, iron, and copper; phenolic acids: p-hydroxybenzoic, caffeic, p-coumaric, and protocatechuic; sterols: lanosterol, ergosterol, ergosterol peroxide; triterpene compounds: betulin, betulinic acid, inotodiol; indole compounds: L-tryptophan, tryptamine, 5-methyltryptamine, melatonin. The content of bioactive substances in the biomass was dependent on both the origin of the host species of the fungus isolate and the type of culture medium. Based on the results of this study, mycelial cultures can be proposed as a potential source of bioactive compounds and are promising naturally derived cytotoxic agents.

In 2019–2020 (for 13 months), 21 macrofungi species, both native (14) and inadvertently introduced from warmer regions (7), were found in greenhouses at the Warsaw University Botanic Garden. These included 13 species recorded for the first time in Polish greenhouses. Descriptions and photographs are given for 5 species identified, which are new to Poland (Gymnopus luxurians, Hemimycena ignobilis, Leucoagaricus meleagris, L. rubrotinctus, and Xylaria arbuscula s.l.). The highest variety of species was found in the greenhouses with the collection of tropical and succulents and cacti, with 11 and 8 species, respectively. The number of species ranged from five to four in other greenhouses. The current results increase the number of species reported from greenhouses in Poland to approximately 50. None of the identified species has a negative impact on the growth and health of plants in the greenhouses at the Warsaw University Botanic Garden and at present none of them are indicated as potentially invasive.

Drought in the forest is not only a prolonged state of water shortage, but also an occasion where interactions between plants and fungi are affected. Water efficiency accelerates a range of pathologies in interactions between organisms, influencing the ecosystems and their interacting biological components. This study focuses on the role of mycorrhizal and endophyte fungi in alleviating the effects of soil water shortage, and on the impact of their altered activity during drought on the health of trees. The issues presented here show the fundamental role of the mycorrhizal mycelium and the mechanism of water transport to the plant in the course of other phenomena (withering, pathogenesis, endophytes biology) that occur in trees under influence of drought, with particular attention on managed coniferous stands. Conclusions resulting from published information on this topic emphasize the negative impact of soil moisture deficiency on the ectomycorrhizal fungi functioning and, in contrast, on the promotion of the growth of some endophytes, pathogens and hemi-parasitic mistletoes (Viscum spp.).

The paper presents the history of the protection of trees with special values, the current state of monument trees and the preliminary description of trees meeting the minimal circumference criteria to be regarded as natural monuments in the Kampinos National Park (KNP). The study was conducted in the years 2017–2019. In the KNP, there are 69 living trees with a status of natural monuments. Most of them are oaks – 56 specimens, Scots pine – 6 specimens, small-leaved lime – 5 specimens and European hornbeam and European ash – 1 specimen each. Among all, 27 trees grow individually and the other 42 grow in 7 groups. About 200 trees were recognised as meeting the minimal circumference criteria to be regarded as natural monuments. The thickest size tree in the KNP is the black poplar with a circumference of 805 cm, growing in the enclave of Ruska Kępa, and the thickest monument tree in the KNP area is Dąb Kobędzy (Kobendza Oak) with a circumference of 582 cm. Almost a half of the living monument trees (34 specimens) are situated in Kampinos Forest District. In Kromnów, there are 20, and in Laski Forest District 15 specimens of monument trees are mapped. Living monument trees were found in 15 (out of 17) forest subdistricts. The highest number of monument trees was found in Rózin Forest Subdistrict (16) and in Wilków Forest Subdistrict (10). The lowest number – one specimen per forest subdistrict – was found in six forest subdistricts (Dąbrówka, Grabina, Janówek, Krzywa Góra, Rybitew and Zamczysko). In total, there are around 300 specimens of natural monuments and trees meeting the minimal circumference criteria to be regarded as natural monuments, which means that there is one tree of this category for each 125 ha surface of the KNP.

The experiment conducted in the Kampinos National Park since 2015 was aimed at assessing the sprouting ability of black cherry (Prunus serotina Ehrh.) in response to different measures of mechanical control and mycobiota colonizing the dying trees. Basal cut-stump, cutting at ca. 1 m above the ground and girdling were performed on 4 terms, two plots and applied to 25 trees, 600 trees in total. Sprouts were removed every 8 weeks since the initial treatment for 4 consecutive growing seasons, except winter-treated trees. At the end of the fourth season of control, 515 out of 600 trees were dead (86%): 81% on Lipków and 90% on Sieraków plot. Among 18 experiment variants with sprouts removal, 17 showed more than 80% of dead trees. The lowest, 76% share, concerned summer cut-stump at the base of the tree. For winter measures, the share of dead trees was lower in all cases and ranged from 28% to 64% proving that sprouts removal contributes to the drop of sprouting strength and quicker dying of the trees. Almost 80% of trees showed sporocarps that represented 51 taxa of macrofungi in total, including 6 Ascomycota and 45 Basidiomycota. The group of six most frequently encountered fungi includes: Hyphoderma setigerum, Bjerkandera adusta, Peniophora cinerea, Armillaria ostoyae, Nectria cinnabarina, Stereum hirsutum. Both plots had similar share of black cherry individuals with sporocarps of macrofungi, that is, 81% and 78% for Sieraków and Lipków respectively. The share of colonized trees and the number of reported macrofungal taxa increased significantly compared to the year following the treatment. In addition, the composition of macrofungi changed with the progressing dying of trees. These results broaden the knowledge about macroscopic fungi colonising and living on black cherry within its secondary range of distribution. Moreover, one macrofungus and two microfungi new for KNP are reported.

In many spruce stands, trees are frequently attacked by the pathogen Heterobasidion parviporum, albeit without visible symptoms in the crown. In the present work, the results of the presence of stem rot, assessed by PICUS Sonic Tomography, and the fungal biota on trees and stumps in eight plots in the Puszcza Borecka Forest are described. The plots were located in stands on original forest soil (4) and on post-agricultural soil (4), where around a stump with H. parviporum symptoms (signs of internal rot and basidiocarps), 30 trees were selected and examined for internal rot. Wood samples were collected from two selected trees for fungal molecular analysis. A total of 79 fungal taxa were found, including 57 taxa in plots on post-agricultural soil and 45 on forest soil. There were 395 fungal records on stumps and 22 records on trees, therein, from the inner parts of felled trunks. Significant differences in the Chao-1 diversity index indicate that the origin of the soil—post-agricultural or forest soil—influenced the alpha diversity of the fungal communities in the forests studied. The values of the Shannon and Simpson indices show that the two communities were similar in terms of species numbers. The presence of basidiomata of H. parviporum and two species of Armillaria (mainly A. cepistipes) in samples on all plots is striking, although Armillaria spp. was detected more frequently. Most of the species identified were typical saprotrophs, although rare species were also found, such as Entoloma byssisedum, Onnia tomentosa, Physisporinus vitreus, Postia ptychogaster, and Ramaria apiculata. The presence of H. parviporum in the inner woody parts was confirmed by PCR analysis, and decay was detected even up to a stem height of 6 m. Armillaria was the dominant genus in the studied stands and plays a significant and underestimated role in heartwood decay of old spruce trees in Puszcza Borecka Forest.

Buglossoporus pulvinus is widely distributed across Europe, within the range of Quercus robur. Throughout the area in which it appears, it is rare or very rare. It is listed as an endangered species in Europe and has been added to the Red Lists of fungi in a number of countries, along with awaiting inclusion in the IUCN Red List. In this study we have critically analysed the existing data about the occurrence of B. pulvinus in Poland. We have presented two new localities of the species in question in Poland, as well as new occurrences on the territory of the Białowieża National Park, the only place where this species had been previously recorded in Poland. Selected trees and logs inhabited by B. pulvinus have been characterized. We have indicated the number of observed basidiomata, their phenology, and the sizes of the largest specimens. We have identified 8 fungus species (Bisporella citrina, Daedalea quercina, Hapalopilus croceus, Hymenochaete rubiginosa, Laetiporus sulphureus, Mycena galericulata, M. inclinata, Xylobolus frustulatus) that coexist with B. pulvinus. Based on the new distribution data for B. pulvinus in Poland, according to IUCN Red List criteria this species should be classified as Endangered (EN).

The Sarcodontia crocea (Schwein.) Kotl. is recorded for the first time from Armenia. The specimen has been collected from the old fallen branch of apple tree (Malus sp.) and known from the single locality, the private orchard at the Vahagni village, Lori province. Herein, the collected specimen, habitat and threats are briefly described. Further inclusion to the Red Data Book of Armenia is recommended.

Pines are generally fire-resistant trees. There is a shortage of research on the behaviour of Scots pine after surface fire in older stands. The aim of the work was to describe the effect of the surface fire intensity on the mortality of pines of various diameter at breast height (DBH), including older trees. The research was conducted in Peucedano-Pinetum oligotrophic Scots-pine forest in Kampinos National Park (KPN, central Poland) on the area of two adjacent surface fire sites originated in spring 2015 in 60- to 200-year-old stands (site area: 10,92 ha). There were 45 (28 burned and 17 control) permanent plots established after the fire. The share of not burned, superficially burned and completely burnout organic horizon of the soil was determined within all of them. DBH and location of pine trees were measured within all of the plots on the area of 200 m2. For all of the trees for which full information about soil organic horizon damage was mapped, the prevailing type of disturbance in their close neighbourhoods with radii of 1 and 2 m was assessed. The mortality of trees was assessed after each vegetation period up to 2017, basing on the presence of green needles on the trees. The influence of fire intensity on the survival of trees was examined on whole permanent plot level as well as on individual tree level. Strong linear correlation was observed between Scots pine mortality and the share of plots area with damaged organic layer, especially at the end of the third vegetation period after fire. Logistic regression models constructed for individual trees suggest that bigger tree diameter (hence, thicker bark) diminished the odds of mortality only after two vegetation periods from the fire. After the third vegetation period, only the intensity of surface fire in the close neighbourhood of trees influenced (negatively) the chance on survival. The size of trees did no matter in this case. Nearly all of the trees that were located within burnout organic matter areas died. The results did not support the commonly known mechanism of enhancement of bigger Scots pine tree survival after surface fire because of thicker bark responsible for heat protection. Probably, the main cause of observed mortality was not overheating of cambium but it was rather connected to massive fine root loses. Scots pines growing on oligotrophic arid sites modify their root system to explore topsoil layers with higher proportion of shallow roots, growing even in organic litter layer. This corresponds with massive (regardless of size) pine mortality within sites characterised by complete burnout of organic matter layer and very high survival in those ones with only surfacely burned litter layer. The results can improve the assessment of surface fires consequences in managed Scots pine stands growing in oligotrophic conditions.

The complexity of invasion process of alien species is very high and requires better understanding. Nowadays, the successful range expansion of Erechtites hieraciifolia is being observed in Poland. In the study, the distribution of the species in Poland was summarized, based on the available literature and new field data. The fieldworks were conducted in the part of the species expansion zone located in central and north-eastern Poland. Two case studies on species encroachment into post-fire and transitional bog communities were performed and a case inventory of the species presence on the border of its main secondary range was conducted. The measurements of height, counting of the number of inflorescences per individual and the number of achenes per flower head were conducted in selected stands. There was performed a checking of local conditions of growth using ecological indicator values for vascular plants. The analyzed specimens of the species had significantly less inflorescences and achenes than in the other parts of the species expansion zone. They grew also in worse light conditions and in less fertile sites. The species colonized most disturbed patches at first. It spread to the less disturbed ones and omitted natural sites. The massive colonization of the transitional bog could be caused by groundwater level lowering. In the area of the edge of the species main range it was found in many diffuse stands within disturbed patches of the landscape. Based on the obtained results the species is considered to create now still only a moderate threat in the analyzed part of the expansion zone. The possibility of its expansion to wetland sites and sudden appearance in Kampinos National Park needs much more attention. Key words: alien invasive species, climate change, American burnweed, expansion, disturbance

Continuation of the mycological study of the fire-damaged pine forest in Kampinos National Park in central Poland in 2017 produced interesting new findings. Among the taxa collected, 36 were new to the park, six had not been hitherto reported from Poland (Calycellina araneocincta, Ciliolarina aff. laetifica, Clitocybe metachroides, Galerina cerina f. longicystis, Parasola cuniculorum, Pleonectria pinicola), and the previous status of one taxon (Pleonectria cucurbitula) had been uncertain. Short descriptions based on collected specimens have been prepared for all taxa new to Poland. The current number of taxa of macromycetes identified in Kampinos National Park has reached 1,604.

We investigated saproxylic moths of the family Tineidae, a neglected group inhabiting wood-decaying fungi and dead wood, within the Bialowieza Primeval Forest in Poland. Study data were obtained from the collection of 280 fruiting bodies of wood-decaying fungi and the subsequent rearing of adults. Spatial and statistical distribution of saproxylic moths, relationship among species and the influence of environment reflected by interaction with tree and fungal species together with tree and stand level characteristics were studied. Fifteen species and 533 individuals of saproxylic moths were reared. The fungal species, number of fruiting bodies and standing position of a tree influenced species richness. Moth abundance was influenced by fungal species, coniferous trees, increasing tree diameter, number of fruiting bodies and brown rot. Moth abundance was also enhanced by standing dead trees located in managed forests with higher canopy closure. Analyses indicate that several moth species favor a particular rot type and that some fungi host a richer fauna than others. Furthermore, our results indicate mutually independent fungal colonization events by saproxylic moth species, and thus a possible mechanism exists for competition avoidance with other saproxylic moths. Saproxylic moths revealed complex within-group patterns that responded differently to environmental variables. Thus, potential conservation of these organisms requires various approaches including ecosystem management, especially in the context of addressing their diverse habitat requirements.

The polypore fungus Spongipellis spumeus is red-listed in Poland and in several other European countries. On the basis of published data and seven new locations, we have presented its distribution in Poland. In the country, S. spumeus was recorded primarily in anthropogenic habitats (tree lines along streets and roads, old orchards, parks), and rarely in forest communities. Two tree species (Acer platanoides, Populus alba) is reported here as a new host of S. spumeus in Poland. The declining acreage of alluvial forests and removal of old trees from substitute habitats (e.g. parks or avenues in cities) seem to be major threat factors for this fungus. Based on the new distribution data for S. spumeus in Poland, it should be rather classified as vulnerable (VU) according to IUCN red-listed criteria, than endangered (E) as it currently is. One beetle species i.e. Tetrotoma fungorum was found on the basidiomata of S. spumeus during the study, that may imply the role of the beetle in spreading of this fungus.

The experiment conducted in the Kampinos National Park since 2015 is aimed at investigating the relationship between the dynamics of black cherry sprouting response and the type and term of implementation of the mechanical elimination procedure. It also identifies macrofungi colonizing trees undergoing eradication. Three treatments, basal cut-stump, cutting (height: ca. 1 m) and girdling, were performed on 4 terms: early and late spring, summer and winter. Each variant was conducted within two plots, and applied to 25 trees, to 600 trees in total. For two consecutive vegetation seasons, sprouts were removed approximately every 8 weeks with the exception of winter-treated trees. Qualitative data were analysed, that is, the number of trees with and without sprouts at subsequent controls, and at the end of the second season, except winter-treated trees. Initially, almost 100% of the trees cut at the base and cut high responded by sprouting. The share of trees without sprouts gradually increased during the following vegetation season, from 3rd to 5th repetition of the sprouts removal, depending on the variant of experiment. Girdling contributed to a delay in sprouting. The effectiveness of procedures, expressed as share of trees without sprouts at the end of the second vegetation season, ranged widely (12%–84%), and depended statistically significantly on the date of the treatment. The effectiveness was higher for treatments done in early (average 68%) and late spring (average 74%), as compared to those done in summer (average 35%). Mycological research concerned 600 trees, including those treated in winter, without sprouts removal. Occurrence of 26 taxa of macrofungi was confirmed on 25% of trees; most of them having wood-decaying properties. Chondrostereum purpureum was most frequent, colonizing 9% of trees. Impact of plots varying soil moisture on succession and rate of fungi colonization, and on sprouting response dynamics requires further research.

Sarcodontia crocea is a fungus relatively rarely recorded in Central and Northern Europe, where as a parasite it grows mainly on old apple trees. The most recent data on the occurrence of this fungus in Poland are presented in this study. Seven new localities of S. crocea are reported, found in the regions of Mazowsze, Podkarpacie, Ziemia Łódzka, and Żuławy Wiślane in the years 2013–2016. The S. crocea basidiomes were recorded on 12 apple trees. The fungus occurrence on Malus pumila ‘Niedzwetzkyana’ was documented for the first time. Four beetle species representing four families were found in the studied S. crocea basidiomes. Their feeding on S. crocea has not been mentioned in the literature so far.

The paper presents 32 species of macrofungi new to the Kampinos National Park, found during the studies on fire-damaged areas after the forest fires in 2015. Three species new to Poland were described and illustrated (Calycellina leucella, Exobasidium juelianum, and Gymnopilus decipiens). Four species from Polish red list of macrofungi have been recorded in the Kampinos National Park for the first time: Botryobasidium vagum (R), Geastrum coronatum (V), Helicogloea farinacea (E), Inonotus cuticularis (R). During the current studies 17 pyrophilous species new to the Kampinos National Park were found.

In 2010, 16 macrofungi species were found in greenhouses of the Botanical Garden in Warsaw-Powsin. These included 8 species of lepiotaceous fungi and a few species known from warmer areas. For 3 species identified, which are new to Poland (Agaricus subrufescens, Leucocoprinus heinemannii, Marasmius teplicensis), a description is given, with drawings of their microscopic features and photographs. Species composition of macrofungi is compared in 5 complexes of greenhouses (Bayreuth, Graz, Jena, Paskov, Warsaw) in 4 countries from Central Europe. The total number of species in these 5 studies is 206, including 27 (13.2%) lepiotaceous fungi. The smallest number of species identified was in Warsaw (16). More than twice this number was recorded in Jena (33) and Graz (34), while the richest fungal biotas were in Bayreuth (79) and Paskov (88). Of the 16 species found in Warsaw, 8 were also found in other greenhouses. In the group of 33 species recorded in at least two complexes of greenhouses, the most abundant were the lepiotaceous fungi (39.4%) and mycenaceous fungi (15.1%). Leucocoprinus cepistipes and L. straminellus were recorded most often, in 4 of the 5 studied greenhouse complexes. CCA analysis demonstrated that the highest impact on species diversity is the area of greenhouses.

New records for twenty species of saproxylic tineid moths (Lepidoptera, Tineidae) from the Białowieża Forest (NE Poland) are presented. Most species were recorded on the basis of laboratory breeding of the adult moths from the sporocarps of wood-decaying fungi inhabited by the larvae. Some species were captured using barrier traps or were collected at light. One species, Dryadaula irinae (Savenkov, 1989), is recorded for the first time from Poland and three others, Nemaxera betulinella (Paykull, 1785), Nemapogon fungivorella (Benander, 1939) and Elatobia fuliginosella Lienig & Zeller, 1846, are recognized as new for the fauna of the Białowieża Forest. The current distribution in Poland of each species is briefly discussed, and some remarks on its biology are given

The current nature of forest management in Poland reflects its history and more than 100 years of economic activity affecting forests since independence in 1918. Before that time, different forest management models were used, related to the nature of the Prussian economy in the north of the country, the Russian economy in the central-eastern part, and the Austrian economy in south-eastern Poland. The consequence of these management models, as well as the differing climate zones in which they were used, resulted in varied forest health. Since the end of World War II, forest coverage within Poland‘s new borders has increased from 20.8% to currently 29.6%, mainly as a result of afforestation of wastelands and former agricultural lands. This paper describes changes in the health of forests and their biological diversity in Poland in the context of weather extremes, species composition, forest management, the forest industry, and damage from insects and pathogenic fungi over the last 30 years.

The paper presents a list of fifty-five coprinoid fungi found in Poland, which have been not reported earlier from this area (28 species) or are known only from few localities. Four species new to Poland collected in Bieszczady Mts and mentioned, without descriptions, in earlier papers, were also included and described in this publication. For the species new to Poland, illustrations and short descriptions based on the specimens examined and literature data, are given.

The paper presents 47 fungi species belonging to the genera Cystolepiota, Echinoderma, Lepiota, Leucoagaricus, Leucocoprinus, Macrolepiota and Melanophyllum, found in Poland, which have been not reported earlier from this area (18 species: Cystolepiota fumosifolia, C. moelleri, C. petasiformis, Echinoderma carinii, E. pseudoasperula, Lepiota angustispora, L. apatelia, L. cingulum, L. cortinarius var. audreae, L. cristata var. felinoides, L. forquignonii, L. rubella, Leucoagaricus cinerascenss, L. ionidicolor, L. sericifer var. sericellatus, Macrolepiota heimii, M. rhodosperma var. rhodosperma, M. venenata) or have been known only from a few localities. For the species new to Poland short descriptions, based on the specimens examined and literature data, are given and their micromorphological characters are illustrated.

In the paper, natural resistance of wood of healthy and damaged common oak (Quercus robur L.) trees to the activity of wood decaying fungi causing brown rot (Coniophora puteana (Schumach.) P. Karst and Laetiporus sulphureus (Bull.) Murrill) and white rot (Trametes versicolor (L.) Lloyd) was examined. The wood samples came from stands aged 60-147 years bearing signs of decline and excessive self-thinning of oak trees. The stands were located in 7 forest districts representing Poland's main sources of oak wood. One healthy and one damaged sample trees were collected from each stand. Wood samples were cut out from outer heartwood at the butt-end of logs. The wood decay test was done according to the norm PN-EN 350-1. The mean width of annual rings and wood density were determined. In general, the wood of healthy trees was decayed to a larger extent than that of damaged ones by two test fungal species (C. puteana and T. versicolor), and in case of L. sulphureus the wood of damaged trees was decayed to the larger extent than the wood of healthy ones. The differences in loss of wood mass were not statistically significant. The loss of wood mass of healthy and damaged oak trees caused by C. puteana was 2.1 and 1.1%, by L. sulphureus - 7.0 and 7.7%, and by T. versicolor - 1.7 and 0.9%, respectively. Analysis of pairs of trees from three different forest districts (Czarna Bialostocka, Miekinia, Mircze) showed somewhat lower resistance of the wood from damaged trees in comparison with healthy ones to the decay caused by three examined fungal species. The situation was the opposite for the two oak provenances of Jablonna and Krotoszyn forest districts where the wood of healthy trees was less resistant than that of damaged ones. In case of wood from two other forest districts of Henrykow and Wolow, no common tendency in decay of wood caused by all three fungal species was found. No geographical variability in loss of wood mass caused by the activity of the test fungi was found between healthy and damaged trees.

In the paper natural resistance of wood of healthy and damaged European beech (Fagus sylvatica L.) trees to the activity of wood decaying fungi producing a white rot - Fomes fomentarius (L.) J. J. Kickx and Trametes versicolor (L.) Lloyd and a brown rot - Coniophora puteana (Schumach.) P. Karst was examined. The wood samples came from stands aged 80-145 bearing signs of decline and excessive self-thinning of beech trees. The stands were located in three forest districts situated in the lowland and three - in the upland/highland region, representing Poland's main sources of beech wood. Two healthy and damaged sample trees were collected from each stand. Wood samples cut out from the trunk at the butt-end of beech trees were used for analysis. The wood decay test was done according to the norm PN-EN 350-1. After sixteen weeks of incubation, the wood of damaged trees was decayed to a larger extent than that of healthy ones by all three test fungal species. The mean loss of the wood mass from healthy and damaged trees caused by C. puteana was 28.6 and 29.7 per cent, by T. versicolor - 23.3 and 25.0 per cent and by F. fomentarius - 18.5 and 20.8 per cent, respectively. The statistically significant difference (Mann-Whitney test) of 1.1 per cent on wood loss was detected only for the wood decayed by C. puteana. Analysis of tree pairs showed a lower resistance of the wood from damaged trees in comparison with healthy ones to the decay caused by the fungi in the majority of the examined beech provenances. No geographical variability in wood mass was found between healthy and damaged trees caused by the activity of the test fungi.

The article presents the results of inoculation of beech and oak stumps with a biological preparation of oyster fungus (Pleurotus ostreatus) mycelium. The inoculum was grown on a sawdust substrate at Warsaw University of Life Sciences Department of Mycology and Forest Phytopathology. The experiment was set up at the Forest Experimental Station in Rogów. Stumps were inoculated: i) immediately after tree felling or ii) at approximately 5 and 12 months after felling. A total of 60 beech stumps and 50 oak stumps were inoculated in the years 2002– 2004. The infected stumps were then inspected for the presence of the mycelium and fruiting bodies of P. ostreatus. The presence of fruiting bodies of other wood-decaying fungi was also noted. The extent of rotting was determined macroscopically, with the causal agent being confirmed on the basis of isolation and identification of mycelium from fragments of colonized wood obtained from rooted-out stumps. Oyster fungus mycelium was found to colonise beech stumps much more effectively than oak stumps. Stumps inoculated immediately after, or five months after felling were more effectively colonized by the mycelium than those inoculated after one year.