Browsing by department "Avdelningen för skogsvetenskaper"

The aim of this study was to investigate if the drainage-based utilization of agricultural peatlands, associated with heavy greenhouse gas (GHG) emissions, really meets the goals of the farmers, and to investigate how well alternatives with lesser GHG emissions could fit the farmers’ needs. Finland has obligations, both national and from European Union, to reduce its total GHG emissions from the levels of 1990 by 39 % until 2030, and 80 % until 2050. Ten percent of Finland’s total GHG emissions come from agricultural sector. Agricultural organic soils represent only about 10 % of total agricultural land in Finland, but it is estimated that the GHG emissions from these organic soils make up to 50-60 % of the total GHG emissions of the whole agricultural sector. The low water table in traditional drainage-based utilization of agricultural peatlands causes rapid decomposition of peat, which leads to high GHG emissions, leaching of nutrients, subsidence and to numerous problems on the fields. According to literature review done, raising of the water table is the most efficient way to reduce GHG emissions on agricultural peatlands, but the raised water table limits the use of traditional crops like cereals. Restoration of the peatland, paludiculture and afforestation have been suggested as alternative uses of these agricultural peatlands in literature. In this study, multi-criteria decision analysis was used to compare different uses of agricultural peatlands in the light of varying goals. Twelve different forms of peatland utilization were selected for the comparison, and these included forms of utilization with both high and low water tables. Firstly, it was investigated what kind of indicators can be used to assess the performance of the different types of utilization, and values for those indicators were gathered from the literature if possible. Weighting of the indicators in relation to the goals of the farmers was planned to be carried out with a questionnaire, but as we did not manage to get any answers from the farmers, the multi-criteria decision analysis was done with weightings collected both from a group of scientists and from a simulation. Traditional forms of drainage-based farming scored well on financial and productional indicators, but they lacked on regulating and cultural indicators. In both analyses with the weighting given by the group of scientists and by simulation, utilization forms of peatlands with high water table were selected as the best alternative for agricultural peatland management significantly more often than the deeply drained alternatives. With the weighting done by the group of scientists the deeply drained forms were selected not once as the best alternative for peatland utilization, and with the weightings extracted from the simulation in only 3,5 % of the cases a deeply drained form of utilization was selected as a best alternative. These multi-criteria decision analyses show, that the wet forms of peatland utilization have a great potential to be selected as the best alternatives of agricultural peatland utilization also with weighting profiles that put heavy weight also in financial indicators, although this requires the market to the alternative materials to be developed. The policy concerning agricultural subsidies likely affects financial attractiveness of the utilization alternatives of peatlands by great extent. Further long-term research of paludiculture is still needed, and field studies on paludiculture should also be started in Finland to improve the assessment of wet peatland use on most indicators.

Kuluttajien ostokäyttäytyminen sekä kulutuspäätökseen vaikuttavat tekijät ovat muuttuneet viimeisien vuosikymmenien aikana. Mainostajan tuotteista antamien väittämien merkitys kuluttajien ostopäätöksissä on vähentynyt. Suusta suuhun- viestinnän merkitys sekä vaikuttajamarkkinointi ovat nousseet merkittäviksi tekijöiksi kuluttajien ostopäätöksissä ja yhä kasvavissa määrin kuluttajat haluavat suosituksen tuotteesta kolmannelta osapuolelta, jolla ei ole tekemistä myyjäosapuolen kanssa. Kuluttajat arvostavat erityisesti vaikuttajia, jotka ovat samaistuttavia, luotettavia sekä asiantuntevia. Vaikuttajailmiö on levinnyt myös sijoitusmaailmaan, muun muassa tv-ohjelmien myötävaikuttamana. Lisäksi viime vuosina on ollut havaittavissa nouseva trendi, jossa vaikuttajat ja julkisuuden henkilöt ovat lähteneet mukaan yritystoimintaa. Tässä työssä perehdyttiin vaikuttajaomistajuuteen ja siihen liittyviin asenteisiin. Työn tarkoituksena oli selvittää laadullisen tutkimuksen menetelmin nuorten aikuisten piensijoittajien suhtautumista vaikuttajaomistajuuteen. Tutkimuksessa selvitettiin, miten nuoret aikuiset piensijoittajat ajattelevat vaikuttajaomistajuudesta ja vaikuttajaomisteisista yrityksistä sekä mitä ajatuksia ja ennakkoluuloja niihin liitetään. Tutkimuksessa pyrittiin myös selvittämään, voisiko vaikuttajaomistajuus olla nuorten aikuisten piensijoittajan sijoituspäätöksentekoprosessiin vaikuttava tekijä. Vastauksia käsiteltiin Ohanian (1990) lähdeuskottavuusmallin mukaisesti. Tutkimusaineisto kerättiin puolistrukturoituina teemahaastatteluina yksilöittäin ja haastatteluita toteutettiin kahdeksan kappaletta. Haastattelut litteroitiin ja analysoitiin sisällönanalyysillä. Tutkimuksessa selvisi, että haastateltavat suhtautuvat avoimesti vaikuttajaomistajuuteen, mutta sen luotettavuus koetaan ongelmallisena. Haastateltavat kokevat vaikuttajaomistajuuden ensisijaisesti markkinoinnin keinona. Siirtymä vaikuttajamarkkinoinnista vaikuttajaomistajuuteen nähdään luonnollisena kehityksenä, jota ohjaa muun muassa paremmat ansaitsemismahdollisuudet. Vaikuttajaomistajuus nähdään pidempikestoisena, syvällisempänä ja sitoutuneempana. Luotettavaan, asiantuntevaan, sitoutuneeseen ja osakkeenomistajan sekä yrityksen tarpeita palvelevaan vaikuttajaomistajaan suhtaudutaan positiivisesti, mutta haastateltavat antavat sille vaihtelevasti painoarvoa omassa sijoituspäätöksessään. Huolimatta vaihtelevista vastauksista liittyen vaikuttajaomistajuuden vaikutuksesta sijoituspäätökseen, tarkasteltaessa vastauksia Ohanian lähdeuskottavuusmallin (1990) mukaisesti luotettavuus, asiantuntemus ja puoleensavetävyys ovat tekijöitä, joita vastaajat arvostivat vaikuttajaomistajassa, joten niiden havaittiin vaikuttavan positiivisesti nuoren aikuisen piensijoittajan sijoituspäätökseen. Tutkimustuloksien mukaan vaikuttajaomistajuudella on positiivinen vaikutus nuoren aikuisen piensijoittajan sijoituspäätökseen. Jatkotutkimusehdotuksena määrällinen tutkimus soveltuisi täydentämään tietoa vaikuttajaomistajuuden vaikutuksesta piensijoittajan sijoituspäätökseen ja arvioimaan vaikutusta.

Aims. The aim of this study is to discover the factors influencing which employees’ experience of organizational commitment during changes in contact center work environment. Meyer and Allen’s three component model of organizational commitment is used as the theoretical frame. It interprets organizational commitment through three components: affective, normative, and continuous commitment. The research focuses on areas impacting affective commitment. Methods. The study was conducted as thematic interviews during the fall of 2019. Seven per-manent employees of the target organization attended the interviews. The material was spelled out, after which it was coded according to the themes. The method of the analysis is thematic design, in which the formation of themes proceeds to a more detailed examination. Results and Conclusions. The most prominent finding in the study was the employees’ experiences of the role and the support of the supervisor for commitment. Reflecting the theoretical frame, the results of this study comply with Meyer & Allen’s three-component theory. Based on the study, the affective commitment of the employees of the target organization can be seen as low, and the level of commitment can be explained by normative or continuance aspects of commitment.

Luonnontuotteiden tuotanto voidaan yhdistää perinteisen puuntuotannon rinnalle osaksi metsätaloutta, jolloin metsänomistajan ansaintamahdollisuudet monipuolistuvat. Luonnontuotealalla vallitsee yleisesti raaka-aine pula ja metsänomistajien aktivointi niiden tuotantoon on tulevaisuuden kannalta erittäin tärkeää. Pakurikäävän viljely on mahdollista ottaa osaksi ensiharvennusikäisten koivikoiden kasvatusta, jossa pakuria kasvatetaan niissä rungoissa, jotka ensiharvennuksen yhteydessä poistetaan. Tämän tutkielman tarkoitus on selvittää pääkaupunkiseudun metsänomistajien suhtautumista ja kiinnostusta luonnontuotteiden ja erityisesti pakurikäävän tuotantoon ja selvittää mitkä tekijät vaikuttavat pakurikäävän kasvatuksen kiinnostavuuteen. Tutkimuksen teoriataustana toimii innovaatioiden diffuusio (diffusion of innovations), jonka pohjalta tarkastellaan pakurikäävän kasvatuksen kiinnostavuuden nykytilaa. Tutkimus suoritettiin internet –pohjaisena kyselytutkimuksena joka julkaistiin Pääkaupunkiseudun metsänomistajat RY:n ja Metsänhoitoyhdistysten metsänomistajien palvelutoimiston (pk-seutu) uutiskirjeissä keväällä 2019. Kyselyn vastausprosentti oli 1,1 % eikä kyselylle suoritettu erikseen katoanalyysiä. Kyselylomake koostui neljästä kysymyskategoriasta, joiden vastaukset olivat viisi portaisella likert –asteikolla. Aineistoa kuvaileva analysointi suoritettiin excel-ohjelmistolla. Tilastollinen analysointi suoritettiin SPSS –ohjelmistolla jossa pääanalyysimenetelmänä käytettiin ristiintaulukointia (χ2 –riippumattomuustestiä) jolla selvitettiin, riippuivatko tarkasteltavat muuttujat toisistaan. Tutkimuksen tulosten perusteella pääkaupunkiseudun metsänomistajat ovat tietoisia ja kiinnostuneita luonnontuotteiden tuotannosta. Pääkaupunkiseudun metsänomistajat ovat innovatiivisuudeltaan innovaattoreita, aikaisia omaksujia sekä aikaista enemmistöä. Puunmyynnin ohella koetaan tarvittavan lisätuloja, ja luonnontuotteiden uskotaan tulevan vakiintuneeksi osaksi metsätalouden harjoittamista. Liian vähäinen käytännöntieto sekä investoinnin kalleus koettiin suurimmaksi kynnykseksi aloittaa pakurikäävän kasvatus. Taustamuuttujien suhteen ei voitu päätellä minkälainen olisi tyypillinen luonnontuotteiden tuotannon aloittava metsänomistaja. Pakurikäävän kasvatus koetaan mielenkiintoiseksi vaihtoehdoksi perinteisen puuntuotannon rinnalle, mutta sen kasvatus on niin uusi menetelmä, ettei sen kannattavuudesta ole vielä varmuutta metsänomistajien keskuudessa. Tietoisuuden lisääntyminen ja kasvatuksen yleistyminen voi hälventää tätä epävarmuutta. Luonnontuotealan yritysten ja metsänomistajien tarpeiden yhdistämisellä voidaan saavuttaa kumpaakin palveleva toimintakokonaisuus. Haasteena on luoda yritysten ja metsänomistajien välille selkeä tuotantoketju. Tulevaisuudessa metsien uudet, monipuoliset ja kestävät käyttömuodot tulevat yleistymään, jolloin metsänomistajien asenteita laajemmin ekosysteemipalveluita kohtaan tulisi tutkia enemmän valtakunnallisessa laajuudessa.

This study is aimed at discovering if Virtual reality (VR) has restorative effects on people and how it compares to real environment as a restorative environment. Theory frame used in this research is Attention restoration theory which is widely used in previous restorativeness studies. As the world is urbanizing rapidly, people spend less time in the nature than ever before. Previous researches have shown that nature has a restorative effect on people and it recovers aimed attention. This research tries to find a solution by using the VR environment as a substitute for real environments as a restorative place. Our hypothesis was; VR does have restorative effect and VR forest is perceived as restorative as physical forest. This VR experience study was executed as a quantitative study that was executed randomly picking students and staff of nearby corporations of university campus. Test subjects were exposed to the VR environment for a five-minute period. Information was gathered via questionnaires that were answered both before and after the VR experience. Both questionnaires measured the mood, vitality and restoration at the moment when answered. The data consisted of N=100. Addition to our own data, we had the data from similar research by Hauru et al (2012). With that it was possible to compare the VR environment to real environments. The results showed that the perceived restorativeness of VR was similar as the real forest environment, but the restorativeness was felt even stronger in the VR environment. People felt significantly better after the experience. From the research point-of-view VR could be used as a restoration in urban areas and for example during workdays/school days. It clearly showed its potential for future use. There is still a little concern about the results, as the participants visited the VR environment only once, the long-term effects are yet unknown. Due to that there is still need for future research regarding the long-term use of VR as a restorative environment.

The construction industry together with the use of buildings generates a significant amount of the European Union’s greenhouse gas emissions and uses vast amounts of energy, materials and water. Increasing wooden multistory construction (WMC) could be a way to enhance the sustainability of the construction sector, since studies have shown that the lifecycle carbon dioxide emissions and energy-use are smaller in wood-framed buildings than in corresponding buildings built with concrete. Several national and multinational authorities have set targets for increasing the share of wood in construction to decrease the environmental impact of the construction sector, but the share of WMC has increased rather slowly despite the political support. According to previous research, the reasons for the slow growth of the industry include for example path dependencies of the construction sector (i.e. that past events affect future decisions and events), attitudes and lack of knowledge. This thesis aims at increasing the knowledge of the profitability of WMC by finding out the perceptions of WMC experts on the current cost level in WMC, discovering factors that affect the profitability and market share of WMC and finding ways to enhance the profitability of WMC. This study is qualitative and was conducted using semi-structured theme interviews. Six professionals of the WMC industry were selected using purposive sampling and interviewed in 2017. The main criterion in the selection process was that the interviewees are in a decision-making, senior level position in their company and have prior experience about WMC. The results of this study indicate that WMC is currently more expensive than building with concrete. According to the results, the main causes for the higher costs are lack of knowledge, low number of actors, costs caused by planning and difficulties in tendering. However, WMC industry professionals believe that the profitability of WMC will increase in the future and that the market share of WMC will grow. Based on the results, the best ways to increase the profitability of WMC are learning from repeated projects, product development, utilizing industrial construction, cooperation with other companies and open dialogue with public administration. Furthermore, the professionals emphasized that wood should become a genuinely competitive construction material and that wooden construction’s competitive advantage should not be dependent on support from politicians, municipalities or city planning.

Urban trees and forests are important for human well-being and the diversity of urban nature. Urban forests maintain biodiversity, improve air quality and offer aesthetic and recreational value. The urban trees have also some negative effects. Trees in bad condition can cause harm or danger to humans property. Dense and shady urban forests may cause feelings of insecurity and tree pollen can cause health problems. The urban trees require intensive management and their condition must be constantly monitored. Maximizing the benefits of urban trees and minimizing disadvantages requires detailed data on urban trees. For this reason, many municipalities and cities maintain a tree register with accurate information on individual city trees. Traditionally, data on urban trees have been collected and updated by field surveys, which is laborious and expensive. New laser scanning methods that produce accurate three-dimensional information offer the opportunity to automatically update the tree register. Interest in utilizing them in urban tree mapping and monitoring has been growing rapidly in recent years. This thesis studied ALS-based individual tree detection methods in urban tree mapping. The aim of this study was to determine whether the accuracy of the automatically generated canopy map from ALS-data could be improved by a semi-automatic method. Initially, a detailed canopy map of trees was produced by automated method. Tree candidates were deliniated from the surface model by utilizing watershed segmentation. The canopy segmentation produced by the automated method was visually modified and incorrectly delimited canopy segments were corrected. This resulted in a semi-automatically produced canopy map. The results of the automatic and semi-automatic canopy segmentation method were compared by determining the detection accuracy of the trees and the modeling accuracy of the tree diameter. The results were compared with the number and the diameter of trees measured in the field. Non-parametric random forest method and the nearest neighbor (kNN) method were used in the diameter modeling process. The study area consisted of nine Helsinki hospital areas with a total area of 47,2 ha. There were 4365 trees and 37 different tree species measured in the field. The automatic method produced 6860 trees and the semi-automatic method produced 3500 trees. Thus, the automatic method produced an overestimation of 57.2% and the semi-automatic method produced an underestimation of 19.5 % compared to the reference trees. The largest overestimation by the automatic method was in the Koskela study area (221.6 %) and the smallest underestimation was produced by the semi-automatic method in the Suursuo study area (75.5 %). 63 % of the canopy segments produced by the automatic method were commission errors and 33% of the canopy segments produced by semi-automatic method were commission errors. With the automatic method, the absolute RMSE of the diameter prediction was 12,84 cm and 10,99 cm with semi-automatic method. The diameter predictions of the whole data were 6 % more accurate with the semi-automatic method. The results of the study showed that the accuracy of the automatically generated canopy map from the laser scanning data can be improved by the semi-automatic method. Tree mapping accuracy improved in terms of both tree detection accuracy and diameter modeling accuracy. Based on the results of the study, it can be stated that the semi-automatic method is useful especially in parkland areas, but in densely wooded forest areas there is still issues to solve make this method practical. The benefits of a semi-automated method should be assessed by comparing the workload with the results. Based on this study, the semi-automatic individual tree detection method used in this work could be useful in the operational mapping and monitoring of urban trees.

Tiivistelmä/Referat – Abstract Myrskyt ovat tutkimusten mukaan suuri yksittäinen syy metsätuhoihin. Ilmastonmuutoksen aiheuttamat voimistuneet myrskyt ja routajaksojen vähentyminen ovat lisänneet myös puiden sähkölinjojen päälle aiheutuneita sähkökatkoksia. Myrskytuhojen takia vuonna 2013 Sähkömarkkinalakia uudistettiin, ja uuden lain myötä sähköverkkoyhtiöt alkoivat rakentaa sähköverkosta toimintavarma ympäristöä kaikissa sääolosuhteissa. Asemakaavan ulkopuolisilla alueilla sähkökatkot saavat tulevaisuudessa kestää pisimmillään 36 tuntia ja asemakaava-alueella korkeintaan 6 tuntia. Sähkölinjan maakaapeloinnin lisäksi tehokas keino sähköverkon toiminnan parantamiseen on olemassa olevan sähkölinjojen vierimetsänhoidon parantaminen. Suurimmat vierimetsästä aiheutuvat riskitekijät ovat tuuli- ja lumituhojen aiheuttamat puiden kaatumiset sähkölinjan päälle. Suurin osa sähköverkkojen jakeluverkosta on keskijännitteistä sähkölinjaa. Sähkölinjan alustaa kutsutaan usein johtokaduksi, ja sen ympärillä olevaa metsää vierimetsäksi. Johtokadun tai vierimetsän leveydelle ei ole virallista määritelmää, mutta monien ohjeistusten mukaan johtokadun leveys tulisi olla kuitenkin 6-10 metriä ja vierimetsän 10-20 metriä. Vierimetsänhoidossa korostuu liian pitkien ja potentiaalisesti sähkölinjan päälle kaatuvien puiden poistaminen ajoissa. Vierimetsänhoitoon käytettävät toimintatavat ja ohjeistukset ovat kirjavia, ja tässä tutkielmassa pyrittiin selvittämään, millaisia raivausmenetelmiä sähköverkkoyhtiöt käyttävät, kuinka vierimetsänhoito on yhtiöiden mukaan onnistunut ja mitkä ovat tärkeimpiä kehityskohteita vierimetsänhoidossa. Tutkielmassa tehtiin kyselytutkimus kymmenelle suomalaiselle sähköverkkoyhtiölle heidän toimintatavoistaan vierimetsänhoidossa. Haastateltavien joukossa oli kaikenkokoisia sähköyhtiöitä pienimmistä kaikkein suurimpiin. Tutkimus koettiin alun perin tarpeelliseksi vierimetsiin liittyvän vähäiset tutkimustiedon ja linjaraivauksia tekevän yrityksen kokemuksien vuoksi. Vierimetsänhoito on kokemuksien mukaan paikoitellen edelleen puutteellista. Tulosten perusteella sähköyhtiöt käyttävät sähkölinjan raivauksissa monitoimikoneraivausta, helikopterilla tehtyä raivausta sekä metsurityönä tehtyä raivausta. Vastaajien mukaan helikopteriraivaus koettiin parhaana menetelmänä, joskin raivausmenetelmien vertailu on haasteellista, sillä menetelmiä käytetään jokseenkin eri tarkoituksiin. Tyytyväisyys sähköyhtiöiden tekemään vierimetsänhoitoon jakautui, ja parannettavaa löytyi etenkin vuorovaikutuksessa maanomistajien kanssa sekä riskipuiden löytämisessä. Ohjeistuksina käytetään etenkin Tapion Hyvän Metsänhoidon Suosituksia. Vierimetsän hoito on käsitteenä vielä uusi, ja sähköverkkoyhtiöt ovat kiinnostuneet vierimetsänhoidosta tosissaan vasta sähkömarkkinalain uudistamisen jälkeen. Uusi tutkimustieto linjaraivauksista on hyödyllistä, sillä aihe on vielä melko vähän tutkittu.

Employment dynamics within the Finnish forest industry are bound to go through change resulting from external forces such as digitalization, globalization and an aging workforce. This places pressure on the industry to attract capable talent while organizations will need to hire and train new employees for future organizational success. Organizational socialization is an integral link between the newcomer and the organization during the first months which influences integration and success of new employees. Onboarding which is often related to organizational socialization has been under researched in academic literature while practitioner literature offers some direction. This qualitative case study considers the impact of sales management principles of sales strategy, customer relationship management and sales technology on organizational socialization to discover which elements should be included in the onboarding process from a sales department perspective in a business-to-business organization. A research-based model of onboarding was utilized as a basis for this study. Thirteen semi-structured interviews were conducted within the case organization. This thesis indicates that there are three distinct factors that influence successful organizational socialization which should be considered when developing onboarding programs. First, previous industry and competitive environment knowledge accelerate organizational socialization. Second, there are numerous internal organizational factors that influence onboarding. Finally, sales strategy, customer relationship management and sales technologies should not be neglected when developing onboarding programs. The impact of sales management principles on newcomer self-efficacy, role clarity, social integration and knowledge of culture is complex and requires attention when developing onboarding programs that socialize new employees. In conclusion, this thesis provides much needed research and insight on the potential methods to develop and achieve onboarding outcomes. When socializing new employees, increased support is needed for those who do not have previous industry experience and increased structure assists in clarity. The onboarding program should have a longer scope than anticipated which clarifies targets to the newcomer. Sales technologies assist in information gathering as well as customer management but adoption stems from user-friendliness, organizational promotion and willingness to learn. Finally, sales mentors are valued and should be utilized during socialization of new employees.

The European spruce bark beetle Ips typographus (L.) is a severe pest of the Norway spruce Picea abies (Karst.). The species usually attacks weakened trees, but in a consequence of a strong abiotic disturbance event, population may increase sufficiently to threaten even healthy trees. In addition to available trees for feeding and reproduction, temperature is the most important factor limiting the damage of the pest. Limiting potential of the pest’s enemies is potentially important but poorly known. There are several predator and parasite species limiting the success of I. typographus. These species are commonly known as natural enemies or natural enemy complex. Occurrences of these species are investigated in this study. Regardless of intensive studies about natural enemies, there are still remarkable gaps in knowledge. While natural enemies could theoretically be used to control pest populations, practical applications in forestry are in a very limited use. Mechanical methods, mainly sanitation and salvation loggings, are instead used to prevent outbreaks from escalating. These management practices prevent outbreak from spreading, although damage caused by loggings may also harm trees and expose these to pathogens. Possibility of using natural enemies as a part of pest control in forestry is considered in this study. Field study was conducted in SE Finland. I. typographus and natural enemy complex were sampled in 2018 by means of trapping logs settled with fixed number of I. typographus individuals. This was conducted in three different stand classes representing different gradation phases in forests to find differences between regulating potential of enemies. Stand classes were chosen based on the visible symptoms of bark beetle infestation and disturbance history. Classes were healthy (no attack), early outbreak (first symptoms and increased pest population) and declined outbreak (earlier outbreak, pest already declined near endemic level). Trapping logs with settled I. typographus were allocated to these classes, and insects emerging from trapping logs were later collected for sampling in sealed funnel traps. I. typographus population level was simultaneously monitored using pheromone traps. Differences between insect occurrences in different stand classes were statistically analysed by Kruskal-Wallis test with 0.05-level of significance for each identified enemy species and families. Spearman correlation was also used to detect any possible relations between different enemy species. Predators emerging from the logs were identified to six coleopteran families. Species were Thanasimus formicarius (Cleridae), Plegaderus vulneratus (Histeridae), Epuraea spp. (Nitidulidae), Rhizophagus spp. (Monotomidae) and from Staphylinidae Quedius plagiatus, Nudobius lentus, Phloeonomus spp., Leptusa spp. and Placusa spp. Family Elateridae was inspected as a single tested group. Predatory flies and parasitic wasps also emerged from the logs, although these were excluded from the current study. Three species had significant preference to certain outbreak classes. P. vulneratus proved most promising regulator in this study. It reproduced rapidly already during the first year of infestation. T. formicarius had significant preference for stand class, but failed to occur in sufficient numbers during the first year of infestation to have impact on the I. typographus population. Staphylids Phloeonomus spp. were very common at all stand classes but preferred healthy class. For both P. vulneratus and Phloeonomus spp. preferences for stand classes were significant, but the regulation effectiveness of these species is relatively unknown. Results suggested that limited resources in the healthy class, similar to managed forests forces both bark beetles and predators into same space, potentially increasing mortality. This result was observed by increased total numbers of beetles in the trapping logs of healthy class in comparison to outbreak classes, while simultaneously prey-predator ratio was also lower. This means that in addition to removing resources, sanitation loggings could also have increasing effect on enemy induced mortality. Small amount of deadwood potentially sustains higher endemic population of enemies, potentially increasing stands resistance to further insect induced disturbances. While some enemies were more common at the declined outbreak class, this claim was not supported by this study.