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This study is concerned with establishing a uniform experimental protocol for the determination of phenolic extractives, which play an essential role in the durability of the wood of selected species included in the field tests. European larch (Larix decidua), Norway spruce (Picea abies), Scots pine (Pinus sylvestris), European oak (Quercus sp.), sweet chestnut (Castanea sativa), and black locust (Robinia pseudoacacia) were included in the study. Extraction yield data were collected for extraction in a Soxhlet apparatus using common polar extraction solvents (ethanol, acetone, methanol, water) and for single static extraction cycles in accelerated solvent extraction (ASE). The suitability of the solvents and the appropriate extraction conditions were evaluated based on the results of gravimetric analysis of hydrophilic extractives, spectrophotometric analysis of total phenols, and chromatographic analysis using high-performance liquid chromatography. Extraction in the ASE system with methanol proved to be a quick and accurate way to prepare samples for chemical analysis of extractives of selected wood species. With the chemical monitoring of targeted phenolic extractives in wood subjected to leaching, we propose a novel protocol suitable also for for measuring the effects of weathering on the natural durability of wood in future studies.

Športne trate so zahtevne za vzdrţevanje, saj so pogosto izpostavljene glivičnim boleznim in plevelom. V zadnjih letih je vse manj registriranih fitofarmacevtskih sredstev za njihovo zatiranje. Med leti 2019 in 2020 je potekal poljski poskus na Laboratorijskem polju Biotehniške fakultete v Ljubljani, sestavljen iz dveh delov, kjer smo v petih različnih mešanicah za športne trate preučevali delovanje treh različnih načinov gnojenja (A - anorgansko gnojilo z dodanim izboljševalcemi tal, B - organsko gnojilo z dodanimi izboljševalci tal in C - anorgansko gnojilo) na pridelek, barvo in zdravstveno stanje ter na vsebnost salicilne kisline in skupnih polifenolov. Pridelek trate je v veliki meri odvisen od temperature tal, padavin in vsebnosti vode v tleh. Na pojav glive Laetisaria fuciformis pa je vplival način gnojenja, saj je bil deleţ okuţbe z glivo najvišji pri uporabi organskih gnojil z nizkim deleţem dušika. Preučevanje vpliva salicilne kisline in skupnih polifenolov na naravno odpornost športnih trat na bolezni je relativno novo področje vzdrţevanja športnih trat. Povprečna vsebnost salicilne kisline je bila najniţja pri C načinu gnojenja, skupnih polifenolov pa je bilo več pri B in C načinih gnojenja. Ugotavljamo, da ima način gnojenja določen vpliv na vsebnost salicilne kisline in skupnih polifenolov v travnih mešanicah, kar je odvisno tudi od okoljskih dejavnikov. V letu 2020 smo v rastlinjaku preučevali zatiranje enoletne latovke (Poa annua L.), ki je eden od najpomembnejših plevelov na nogometnih tratah. Raziskovali smo učinkovitost proheksadion kalcija, etefona in bakterije Pseudomonas fluorescens proti travam P. annua L., Lolium perenne L. in Poa pratensis L. Mezotrion je bil uporabljen kot pozitivna kontrola in netretirana trava kot negativna kontrola. Ugotavljamo, da je učinkovitost testiranih pripravkov povezana z vrsto trave in od tega, ali je bila trava pred škropljenjem pokošena ali ne. Rezultati poskusa so pokazali, da z uporabo proheksadion kalcija in bakterije P. fluorescens lahko zaviramo širjenje enoletne latovke na nogometnih igriščih. Sport turfgrasses are the most demanding to maintain because they are often exposed to fungal diseases and weeds. In recent years, there are fewer and fewer registered phytopharmaceuticals for their treatment. Between 2019 and 2020 we carried out a field experiment at the Laboratory field of the Biotechnical Faculty in Ljubljana composed of two parts, studying the response of five different sport grass mixtures to three different fertilization schemes (A – inorganic fertilizer with two soil improvers, B – organic fertilizer with two soil improvers and C – inorganic fertilizer) on herbage mass, colour and health, also on salicylic acid and total phenolic contents. Herbage mass is largely dependent on soil temperature, precipitation and soil water content. The occurrence of the fungus Laetisaria fuciformis was influenced by the fertilization scheme, as the % infection with the fungus was highest when organic fertilizers with low % nitrogen were used. Researching the effect of salicylic acid and total polyphenols on the natural resistance of sports turfgrasses to diseases is a relatively new area of sports turf maintenance. The average content of salicylic acid was significantly lowest under fertilization scheme C, but total polyphenols were higher under fertilization schemes B and C. We conclude that the method of fertilization has a certain effect on the salicylic acid and total polyphenols content in turfgrass mixtures, which also depends on environmental factors. In 2020 was conducted a greenhouse experiment to investigate the suppression of annual bluegrass (Poa annua L.), which is one of the main weeds of sport turfgrasses. We studied the efficacy of prohexadione calcium, ethephon and Pseudomonas fluorescens against P. Annua L., Lolium perenne L. and Poa pratensis L. Mesotrione was used as a positive control and nontreated grass was used as a negative control. We established that the efficacy of the tested products is connected to grass species and whether the grass was mowed/cut before spraying. The results of this study have indicated that the application of prohexadione calcium and P. fluorescens can inhibit the spread of annual bluegrass on football pitches.

Pričujoče poročilo opisuje testne postopke in prinaša rezultate raziskave fizikalnih in mehanskih lastnosti, naravne odpornosti proti glivam ter vsebnost silikatov za 28 tropskih listavcev, ki pred tem še niso bili tehnološko preiskani. Poskusna drevesa so bila v 1970ih letih izbrana v nedotaknjenem gozdu jugozahodnega dela Centralno afriške republike, takrat Centralnoafriškega cesarstva. Vsi testi so bili izvedeni v skladu z mednarodno sprejetimi standardi za male, gladko obdelane vzorce brez napak. Podana je diskusija o uporabnosti preiskanih lesnih vrst. The present report describes the test procedures and presents the results of a study on the physical and mechanical properties, natural decay resistance and silica content of 28 tropical hardwoods which ere not tested prior to that time. The test trees were selected in the 1970ies in the virgin forests of the southwest Central African Republic, then the Central African Empire. All tests were carried out according to internationally accepted standards for small, smooth, defect-free samples. The potential end-use of the wood species tested is discussed.

Wood in outdoor applications is subject to various decomposition factors. Wood degradation can be prevented by construction details, biocide protection of wood, wood modification or selection of naturally durable species. Unfortunately, most species in Europe do not have naturally durable wood. Imported tree species represent a new pool from which we can draw wood species with better natural durability and better resilience towards climate change. The performance of wood when used outdoors depends on the biologically active compounds (extractives) and the water exclusion efficacy. Considering decay, presence of biologically active compounds and water exclusion efficacy, we can estimate the density, modulus of elasticity, extractive content and resistance dose, which reflects the material properties of wood. Recently, the most commonly used model for this purpose is Meyer-Veltrup. Literature data indicate that the durability of the wood from native and new sites is not always comparable, so it is necessary to determine the resistance of non-native wood species from new sites. This paper presents original data on the wood’s overall durability from American Douglas fir (Pseudotsuga menziesii) grown in Slovenia. Experimental data show that the mature heartwood of Douglas fir is more durable than the wood of European larch (Larix decidua). Durability can be attributed to good water exclusion efficacy and inherent durability. Inherent durability is primarily the result of the high content of extractives. Based on the results, it can be concluded that American Douglas fir grown in Central Europe has a high potential for outdoor use.

Service life planning with timber requires reliable models for quantifying the effects of exposure-related parameters and the material-inherent resistance of wood against biotic agents. The Meyer-Veltrup model was the first attempt to account for inherent protective properties and the wetting ability of wood to quantify resistance of wood in a quantitative manner. Based on test data on brown, white, and soft rot as well as moisture dynamics, the decay rates of different untreated wood species were predicted relative to the reference species of Norway spruce (Picea abies). The present study aimed to validate and optimize the resistance model for a wider range of wood species including very durable species, thermally and chemically modified wood, and preservative treated wood. The general model structure was shown to also be suitable for highly durable materials, but previously defined maximum thresholds had to be adjusted (i.e., maximum values of factors accounting for wetting ability and inherent protective properties) to 18 instead of 5 compared to Norway spruce. As expected, both the enlarged span in durability and the use of numerous and partly very divergent data sources (i.e., test methods, test locations, and types of data presentation) led to a decrease in the predictive power of the model compared to the original. In addition to the need to enlarge the database quantity and improve its quality, in particular for treated wood, it might be advantageous to use separate models for untreated and treated wood as long as the effect of additional impact variables (e.g., treatment quality) can be accounted for. Nevertheless, the adapted Meyer-Veltrup model will serve as an instrument to quantify material resistance for a wide range of wood-based materials as an input for comprehensive service life prediction software.

Durability-based designs with timber require reliable information about the wood properties and how they affect its performance under variable exposure conditions. This study aimed at utilizing a material resistance model (Part 2 of this publication) based on a dose–response approach for predicting the relative decay rates in above-ground situations. Laboratory and field test data were, for the first time, surveyed globally and used to determine material-specific resistance dose values, which were correlated to decay rates. In addition, laboratory indicators were used to adapt the material resistance model to in-ground exposure. The relationship between decay rates in- and above-ground, the predictive power of laboratory indicators to predict such decay rates, and a method for implementing both in a service life prediction tool, were established based on 195 hardwoods, 29 softwoods, 19 modified timbers, and 41 preservative-treated timbers.

Wood is one of the most important building materials. During the service life of wood and derived materials, various degradation factors affect performance. To assess how weathering influenced the material resistance and moisture dynamics of wood, 11 different materials were exposed to natural weathering for 9, 18 and 27 months or artificial accelerated weathering. Afterwards, the moisture performance of wood was determined in line with the Meyer-Veltrup procedure. Weathered samples were also exposed to the brown-rot fungus Gloeophyllum trabeum for 16 weeks. Respective materials were classified into durability classes according to EN 350, and relative resistance dose (Drd rel) was calculated. Weathering resulted in leaching of biologically active extractives, changed surface morphology and increased permeability. All these changes were reflected in decreased relative resistance dose for all tested materials. The largest deceases were determined for thermally modified wood, Scots pine, European larch and sweet chestnut heartwood. Nasl. z nasl. zaslona. Opis vira z dne 18. 3. 2021. Bibliografija: str. 556-557.

Namen raziskave je bil preučiti vsebnost celokupnih fenolov ter organskega ogljika v izpirkih treh različnih lesov: domači kostanj (Castanea sativa Mill.), navadna bukev (Fagus sylvatica L.), navadna smreka (Picea abies L.) in navadna smreka zaščitena z baker-etanolaminskim pripravkom Silvanolin%. Prav tako nas je zanimala sprememba tlačne trdnosti vzorcev. Ti so bili izpostavljeni 3. razredu izpostavitve v obdobjih med 4 in 30 mesecev. Topni organski ogljik v izpirkih smo določili s TOC analizo, delež celokupnih fenolov pa z UV-VIS spektrofotometrijo. Meritve tlačne trdnosti smo opravili s strojem Zwick-Roell na zračno suhih vzorcih. Ugotovili smo, da se ob daljšem času izpostavitve delež ekstraktivov poveča, kar se odraža v večjem deležu topnega organskega ogljika in/ali celokupnih fenolov. Razlog za povečan delež ekstraktivov je predvsem biotska razgradnja lesa. Pri določanju tlačne trdnosti smo pri vseh lesnih vrstah ugotovili, da je ta obratno sorazmerna s časom izpostavitve vremenskim vplivom. The purpose of this thesis was to examine the total content of phenols and total organic carbon in the eluate of three different wood species: sweet chestnut (Castanea sativa Mill.), European beech (Fagus sylvatica L.), Norway spruce (Picea abies L.) and Norway spruce protected by a copper-ethanolamine preservative Silvanolin%. The research also explores the change of the compressive strength of the samples. They were exposed to third class exposure in periods between 4 and 30 months. Soluble organic carbon in the eluates was determined by TOC analysis, whereas the proportion of total phenols by UV-VIS spectrophotometry. Furthermore, measurements of compressive strength were performed with the machine Zwick-Roell on air-dried samples. The results show that longer exposure time increases the share of extractives, which is reflected in the greater proportion of soluble organic carbon and / or total phenols. The increased proportion of extractives is mainly caused by bio-degradation of wood. Finally, the study reveals that compressive strength in all wood species is inversely proportional to the time of exposure to weather conditions.

Od nekdaj spada les med najpomembnejše gradbene materiale. V času zavedanja podnebnih sprememb, ki jih je povzročil človek, še dodatno pridobiva na pomenu kot okoljsko zelo ustrezen material. Njegova raba ne obremenjuje okolja in je zelo ugodna za bivanje. Namen projekta je bil ugotoviti, kakšne so izbrane lastnosti hrastovine po več desetletjih uporabe. V ta namen smo uporabili približno 150 let star podporni del ostrešja (roka), izdelanega iz hrastove jedrovine. Fungicidne lastnosti smo ugotavljali z izpostavitvijo 5 različnim glivam Gloeophyllum trabeum, Antrodia vaillantii, Hypoksylon fragiforme, Pleurotus ostreatus in Trametes versicolor. Mehanske lastnosti (upogibno trdnost, modul elastičnosti in tlačno trdnost) smo določili z univerzalnim testirnim strojem Zwick, s tenziometrom pa kapilarni navzem vode. Opravili smo tudi ekstrakcijo po Soxhletu s 3 topili: vodo, 70 % metanolom in cikloheksanom. Stara hrastoina ima slabšo odpornost na lesne glive, najbolj je to izrazito pri delovanju glive G. trabeum. S staranjem pa pada delež ekstraktivnih snovi. Since ancient times the wood is one of the most important building materials. Because of climate change caused by man the wood is even more important as an ecologically very suitable material for living, and from the environmental point of view. We researched changes of some of the most important characteristics of oak wood. We used about 150 years old supporting part of the roof made from oak heartwood. Fungicidal properties were determined by subjecting the samples to 5 different fungi: Gloeophyllum trabeum, Antrodia vaillantii, Hypoksylon fragiforme, Pleurotus ostreatus andTrametes versicolor. Mechanical properties (bending strength, module of elasticity and compressive strength) were measured with a universal machine Zwick the capillary uptake of water with tensiometer. We also made extraction by Soxhlet method. We used 3 different solvents: water, 70 % methanol and cycloheksane. Compared with the control oak wood, the old oak depends on the fungi the timber was exposed to. In the old oak wood, according to the control oak, the mass loss is almost 10 times larger after exposure to rusty gilled polypore (Gloephyllum trabeum). With the aging oak capillary uptake of water and mechanical properties suffer minimal or no change. Partial decline with age was observed in the proportion of extractives.

Kostanjevino uvrščamo med najbolj naravno odporne slovenske lesne vrste. V literaturi zasledimo, da je najpomembnejši dejavnik naravne odpornosti kostanjevine vsebnost velikega deleža ekstraktivnih snovi. V diplomski nalogi smo želeli raziskati, kakšna je naravna odpornost kostanjevine proti lesnim glivam. Z namenom odgovoriti na to vprašanje, smo vzorce dimenzij 1 cm x 1,5 cm x 4 cm izdelali iz jedrovine pravega kostanja in jih nato izpostavili sedmimi glivami razkrojevalk lesa: navadni tramovki, beli hišni gobi, zimskemu ostrigarju, dlakavi slojevki, pahljačici, ogljeni kroglici in svetlikavi pološčenki. Glivam razkrojevalkam smo za primerjavo izpostavili tudi kontrolne vzorce bukovine in smrekovine. Izgubo mase in vlažnosti po dvanajstih tednih smo določili gravimetrično. Ugotovili smo, da so vzorci jedrovine pravega kostanja povsem odporni proti glivam razkrojevalkam, saj je izguba mase, zaradi delovanja najbolj aktivne glive, nižja od 5 %. Ta podatek kostanjevino uvršča med najbolj odporne lesne vrste - v prvi odpornostni razred Chestnut wood is one of the most naturally durable Slovenian wood species. According to literature data, the most important factor of chestnut's natural durability is the fact that it contains a high portion of biologically active extractives. In this thesis we wanted to explore the natural durability of sweet chestnut against wood decay fungi. In order to do elucidate this property, samples from the heartwood of sweet chestnut (Castanea sativa), of the following dimensions (1 cm x 1.5 cm x 4 cm) were prepared, and exposed to seven different wood decaying fungi, namely the brown rot fungus (Gloeophyllum trabeum), the white pore fungus (Antrodia vaillantii), the oyster fungus (Pleurotus ostreatus), the hairy curtain crust fungus (Stéreum hirsútum), the split gill fungus (Schizophyllum commune), the red cushion hypoxylon fungus (Hypoxylon fragiforme), and the lingzhi or reishi fungus (Ganoderma lucidum). In order to make a comparison, control samples from beech wood and Norway spruce wood were prepared and exposed to the same wood decaying fungi. After twelve weeks of exposure mass loss and moisture content was gravimetrically determined. We have established that the samples from the heartwood of sweet chestnut are completely resistant to wood decaying fungi since the loss of mass as a result of decay the most severe fungi was lower than 5 %. This result clearly supports the classification of chestnut wood into the first durability class, and prove it to be one of the most resistant wood species

Cemprin je bil v zadnjem obdobju deležen velike pozornosti, v našem okolju pa še ni povsem uveljavljen. Ker je zanimanje za les cemprina vedno večje, smo se odločili, da raziščemo njegovo odpornost proti glivam. Odpornost je lastnost izjemnega pomena, saj če ima les vse pozitivne lastnosti razen ustrezne odpornosti, ga ne moremo uporabiti na prostem. V ta namen smo les cemprina izpostavili trem različnim glivam. Poskus smo izvedli tako, da smo iz dveh plohov cemprina najprej izžagali po 4 skupine preizkušancev. Ena skupina je bila iz beljave, ostale tri pa iz različno stare jedrovine. Iz vsake skupine smo vzeli 5 vzorcev za ekstrakcijo, nato pa smo skupine še prepolovili in jih polovico umetno starali, preden smo jih izpostavili glivam. Med vsako operacijo smo vzorcem določili maso in tako dobili podatke za izračun želenih informacij. Po končanih testiranjih smo obdelali podatke in ugotovili, da ima cemprin kljub velikemu deležu ekstraktivov v lesu slabo odpornost na glive razkrojevalke. Umetno staranje lesa cemprina bistveno ne vpliva na odpornost. Glede na rezultate testiranja smo les cemprina uvrstili v 4. razred odpornosti, med manj odporne lesne vrste in ga lahko primerjamo s smrekovino. Pinus cembra is getting more and more popular every day, whereas in our region it is still not that well established. As the interest for the use of this wood is growing bigger, we decided to make a research about its resistance to fungal decay. The resistance is a characteristic of great value, because having all the characteristics but lacking suitable resistance, the wood cannot be used outdoors. For this purpose we exposed Pinus cembra wood to three different fungi. The test was made by sawing two boards into four groups of specimens. One group consisting of sapwood, another three of heartwood of different ages. After we had chosen five samples for extraction from each group, we divided the groups and aged half of them artificially, the other half remained unaged. Finally we exposed them to fungi. During all these procedures the mass of samples was determined in order to get the necessary data for the following research. After testing the data was analysed and we concluded that Pinus cembra, in spite of high share of extractives, possesses weak resistance to wood-decay fungi. Artificial aging of Pinus cembra does not affect significantly its resistance. According to the test results we classified the wood of Pinus cembra to the fourth resistance class, i.e. among less resistant wood species and it can be easily compared to spruce wood.

Cemprin je bil v zadnjem obdobju deležen velike pozornosti, v našem okolju pa še ni povsem uveljavljen. Ker je zanimanje za les cemprina vedno večje, smo se odločili, da raziščemo njegovo odpornost proti glivam. Odpornost je lastnost izjemnega pomena, saj če ima les vse pozitivne lastnosti razen ustrezne odpornosti, ga ne moremo uporabiti na prostem. V ta namen smo les cemprina izpostavili trem različnim glivam. Poskus smo izvedli tako, da smo iz dveh plohov cemprina najprej izžagali po 4 skupine preizkušancev. Ena skupina je bila iz beljave, ostale tri pa iz različno stare jedrovine. Iz vsake skupine smo vzeli 5 vzorcev za ekstrakcijo, nato pa smo skupine še prepolovili in jih polovico umetno starali, preden smo jih izpostavili glivam. Med vsako operacijo smo vzorcem določili maso in tako dobili podatke za izračun želenih informacij. Po končanih testiranjih smo obdelali podatke in ugotovili, da ima cemprin kljub velikemu deležu ekstraktivov v lesu slabo odpornost na glive razkrojevalke. Umetno staranje lesa cemprina bistveno ne vpliva na odpornost. Glede na rezultate testiranja smo les cemprina uvrstili v 4. razred odpornosti, med manj odporne lesne vrste in ga lahko primerjamo s smrekovino. Pinus cembra is getting more and more popular every day, whereas in our region it is still not that well established. As the interest for the use of this wood is growing bigger, we decided to make a research about its resistance to fungal decay. The resistance is a characteristic of great value, because having all the characteristics but lacking suitable resistance, the wood cannot be used outdoors. For this purpose we exposed Pinus cembra wood to three different fungi. The test was made by sawing two boards into four groups of specimens. One group consisting of sapwood, another three of heartwood of different ages. After we had chosen five samples for extraction from each group, we divided the groups and aged half of them artificially, the other half remained unaged. Finally we exposed them to fungi. During all these procedures the mass of samples was determined in order to get the necessary data for the following research. After testing the data was analysed and we concluded that Pinus cembra, in spite of high share of extractives, possesses weak resistance to wood-decay fungi. Artificial aging of Pinus cembra does not affect significantly its resistance. According to the test results we classified the wood of Pinus cembra to the fourth resistance class, i.e. among less resistant wood species and it can be easily compared to spruce wood.

V zadnjem obdobju se raba lesa veča, še posebno za gradbene namene. Na prostem je les izpostavljen delovanju biotskih in abiotskih dejavnikov razkroja. Teh procesov ne moremo preprečiti, s pravilnim načrtovanjem konstrukcij, izbiro ustreznih lesnih vrst ali biocidno zaščito pa jih lahko zelo omejimo. Pri izbiri lesa je eden od najpomembnejših podatkov njegova naravna odpornost. Letos je bil objavljen nov standard, ki na tem področju prinaša številne novosti. Najbolj izrazito je zmanjšanje odpornosti macesnovine in hrastovine, predvsem zaradi variabilnosti lesa, ki je v celoti ne znamo pojasniti. V tem prispevku so navedena najnovejša spoznanja in nekateri rezultati, ki se nanašajo na naravno odpornost in življenjsko dobo lesa. The use of wood is increasing in the recent years, predominately in the building sector. Wood in outdoor applications is exposed to a variety of biotic and abiotic degradation factors. These processes cannot be completely prevented, but can be slowed down with proper construction, selection of wood species and/or application of biocides. One of the most important criteria that influences the selection of wood species is natural durability. There has been new EN standard published recently that brings new classification of wood species to durability classes. The most important decrease of durability has been assigned to larch and oak wood, predominately due to the huge variability that cannot be fully controlled. In the respective contribution, new aspects and data that are related to durability and service life of wood are presented.

V raziskavi smo preučevali življenjsko dobo lesa, izpostavljenega na prostem, v tretjem razredu izpostavitve, z dvoslojnim testom. V prvem delu raziskave smo naravnim razmeram izpostavili vzorce smrekovine, impregnirane z vodnimi emulzijami montana in polietilenskih voskov v kombinaciji z borovimi spojinami. V drugem delu testa pa smo testirali vzorce, zaščitene z baker-etanolaminskim pripravkom na vodni osnovi (Silvanolin) in posameznimi sestavinami tega pripravka. Za primerjavo smo izpostavili tudi nezaščitene vzorce smrekovine, macesnovine, bukovine in hrastovine. Skozi celotno obdobje izpostavitve smo spremljali klimatske podatke pod vzorci in na vremenski postaji. Rezultati kažejo, da impregnacija z emulzijami voskov in pripravki na osnovi bakra podaljšuje življenjsko dobo lesa, a je zaščita s pripravki na osnovi bakrovih spojin boljša. Odpornost lesa, zaščitenega z emulzijami voskov in baker etanolaminskimi pripravki, je odvisna od koncentracije emulzije/ raztopine in kakovosti lesa. Na podlagi spremljanja vlažnosti in temperature lesa smo ugotovili, da se v lesu ustvarjajo ustreznejše vlažnostne razmere za razvoj gliv, kot bi sklepali iz meritev temperature in vlažnosti zraka. In our research, service life of wood exposed outdoor in the third use class, determined with double layer test, was investigated. In the first part of the investigation, Norway spruce wood specimens were impregnated with montan and polyethylene water based wax emulsion in combination with boron compounds. In the second part of the research, Norway spruce wood samples were impregnated with a copper-ethanolamine (Silvanolin) water based solution and aqueous solutions of individual components. For comparison, untreated Norway spruce, larch, beech and oak wood specimens were exposed as well. During exposition time, climate data under specimens and at weather station were recorded. The results showed that impregnation with wax emulsions and copper based solutions prolongs service life of wood, but protection with copper-ethanolamine solutions is considerably better. Resistance of wood, preserved with wax emulsions and copper-ethanolamine solutions, was influencedby concentration of emulsions/solutions and wood quality. The parallel measurements of wood moisture content and wood temperature clearly showed that there were more suitable conditions in wood for development and growth of fungi than indicated by air temperature and relative air humidity measurements.

Bukovina sodi med najpomembnejše lesne vrste v Sloveniji. Standard SIST EN 350-2 uvršča bukovino med lesne vrste z najslabšo odpornostjo proti lesnim glivam. To je eden izmed najpomembnejših razlogov, ki preprečuje uporabo bukovine na prostem. Večina podatkov o odpornosti bukovine temelji na laboratorijskih testiranjih, realnih terenskih testov pa je relativno malo. Življenjska doba bukovine je v veliki meri odvisna od lokalnih podnebnih razmer, zato je nujno določiti življenjsko dobo posameznih lesnih vrst na prostem v osrednji Sloveniji. Na Oddelku za lesarstvo zato že več let potekajo testi, s katerimi določamo odpornost bukovine v tretjem razredu uporabe (na prostem, ni v stiku z zemljo). Prvi znaki glivnega razkroja se pojavijo že po nekaj mesecih izpostavitve, kasneje se razkroj nadaljuje, vzorci pa povsem propadejo po 4 do 6 letih izpostavitve. Glavni razlog za dovzetnost bukovine za glivni razkroj je povezan z odsotnostjo biološko aktivnih snovi (ekstraktivov) in dejstvom, da se bukovina relativno hitro navlaži. Z namenom proučiti dinamiko vlaženja bukovine smo petnajst mesecev stalno spremljali vlažnost lesa v različnih razmerah uporabe. Pričakujemo, da bomo skozi daljše obdobje spremljanja relevantnih lastnosti bukovine, preostalih lesnih vrst in modificiranega lesa pridobili podatke, ki bodo omogočili širšo rabo bukovega lesa na prostem. Beech wood is amongst the most important wood species in Slovenia. The EU standard EN 350-2 classifies beech wood into the group of the least durable wood species. This is one of the most important reasons which limit the use of beech wood in outdoor applications. The majority of the data about beech wood durability is a result of laboratory tests as there were limited numbers of field tests performed. As the service life of wood significantly depends on the local climate conditions, this data cannot be simply copied from other countries. Therefore, field tests have been running at the field test site of the Department of Wood Science and Technology for several years now to determine comprehensive performance of most important Slovenian wood species including beech wood. Majority of the tests are performed in use class 3 applications (above ground, not covered). The first signs of decay on beech wood are visible after few months of exposure. Afterwards the decay proceeds and the samples are degraded between 4 and 6 years of exposure. The most important reasons for insufficient outdoor performance of beech wood are lack of biologically active extractives and low water exclusion efficacy. In order to elucidate this phenomenon moisture content was continuously monitored for 15 months. We believe that the field tests performed will lead us to the data which will enable better understanding of the phenomena of durability and improve durability of beech wood with state of the art modification solutions.

V raziskavi smo preučevali življenjsko dobo lesa, izpostavljenega na prostem, v tretjem razredu izpostavitve, z dvoslojnim testom. V prvem delu raziskave smo naravnim razmeram izpostavili vzorce smrekovine, impregnirane z vodnimi emulzijami montana in polietilenskih voskov v kombinaciji z borovimi spojinami. V drugem delu testa pa smo testirali vzorce, zaščitene z baker-etanolaminskim pripravkom na vodni osnovi (Silvanolin) in posameznimi sestavinami tega pripravka. Za primerjavo smo izpostavili tudi nezaščitene vzorce smrekovine, macesnovine, bukovine in hrastovine. Skozi celotno obdobje izpostavitve smo spremljali klimatske podatke pod vzorci in na vremenski postaji. Rezultati kažejo, da impregnacija z emulzijami voskov in pripravki na osnovi bakra podaljšuje življenjsko dobo lesa, a je zaščita s pripravki na osnovi bakrovih spojin boljša. Odpornost lesa, zaščitenega z emulzijami voskov in baker etanolaminskimi pripravki, je odvisna od koncentracije emulzije/ raztopine in kakovosti lesa. Na podlagi spremljanja vlažnosti in temperature lesa smo ugotovili, da se v lesu ustvarjajo ustreznejše vlažnostne razmere za razvoj gliv, kot bi sklepali iz meritev temperature in vlažnosti zraka. In our research, service life of wood exposed outdoor in the third use class, determined with double layer test, was investigated. In the first part of the investigation, Norway spruce wood specimens were impregnated with montan and polyethylene water based wax emulsion in combination with boron compounds. In the second part of the research, Norway spruce wood samples were impregnated with a copper-ethanolamine (Silvanolin) water based solution and aqueous solutions of individual components. For comparison, untreated Norway spruce, larch, beech and oak wood specimens were exposed as well. During exposition time, climate data under specimens and at weather station were recorded. The results showed that impregnation with wax emulsions and copper based solutions prolongs service life of wood, but protection with copper-ethanolamine solutions is considerably better. Resistance of wood, preserved with wax emulsions and copper-ethanolamine solutions, was influencedby concentration of emulsions/solutions and wood quality. The parallel measurements of wood moisture content and wood temperature clearly showed that there were more suitable conditions in wood for development and growth of fungi than indicated by air temperature and relative air humidity measurements.

Na vzorcih lesa evropskega in ameriškega oreha (Juglans regia L. in Juglans nigra L.) smo opravili meritve barve s sistemom CIEL*a*b. Z laboratorijskim testom naravne odpornosti in mikroskopsko smo ovrednotili posledice razkroja z glivami: pisano ploskocevko (Trametes versicolor), rjavo tramovko (Gloeophyllum trabeum ) in belo hišno gobo (Poria vaillantii). Rezultati kažejo, da pri evropskem in ameriškem orehu lahko z meritvami svetlosti ločimo beljavo od jedrovine. Z meritvami barve razlikovanje med lesnima vrstama ni mogoče, lahko pa vrsti ločimo lesno anatomsko. Ameriški oreh v lesu vsebuje romboidne kristale in ima heterogeno trakovno tkivo, evropski pa nima kristalov in ima homogene trakove. Testi naravne odpornosti so pokazali, da je evropski oreh manj odporen na delovanje pisane ploskocevke in da sta predela beljave in stržena manj odporna v primerjavi z jedrovino in predelom prog. Pri izpostavitvi rjavi tramovki so rezultati testa primerljivi. Pri izpostavitvi beli hišni gobi se je ameriški oreh izkazal za bolj odpornega od evropskega. Beljava in stržen obeh drevesnih vrst sta manj odporna od jedrovine. Izkazalo se je, da sta predela prog in jedrovine obeh drevesnih vrst bolj odporna kot beljava in stržen, ter da prihaja do razlik v stopnji razkroja pri delovanju različnih gliv. Pod mikroskopom smo na mikroskopskih preparatih lesa prikazali posledice razkroja celičnih sten zaradi delovanja različnih gliv. Measurements of wood colour were performed on wood specimens of the European and American walnut (Juglans regia L. and Juglans nigra L.) using the system CIEL*a*b. A laboratory test of natural durability was carried out and the effects of fungal decay of wood were demonstrated microscopically. The fungi used in the experiment were white rot fungi Trametes versicolor and brown rot fungi Gloeophyllum trabeum and Poria vaillantii. The results show that it is possible to distinguish sapwood from heartwood of the European and American walnut through brightness measurements. The 2 species cannot be distinguished using measurements of wood colour however, it is possible to distinguish them anatomically. American walnut wood contains rhomboid crystals and has heterogeneous ray tissue European walnut wood does not contain crystals and has homogeneous rays. Tests of natural durability show that the European walnut is less resistant to Trametes versicolor activity and that sapwood and pith are less resistant than heartwood and streaks. At exposure to Gloeophyllum trabeum, the test results for the 2 species were equivalent moreover, the sapwood and pith areas turned out to be less resistant. At exposure to Poria vaillantii, the American walnut proved to be more resistant than the European walnut. The sapwood and pith of both species are less resistant than heartwood. The results show that the streak area and the heartwood of both species are more resistant than sapwood and pith, and that individual fungi cause different stages of decay. The effects of decay of cell walls due to activity of different fungi were presented with microscopic images.

Raziskali smo naravno odpornost kokosove palme (Cocos nucifera) in kavčukovca (Hevea brasiliensis) na glive povzročiteljice trohnenja iz našega geografskega področja. Naravno odpornost smo preizkusili z mini blok testom. S testiranjem smo ugotovili, da so glive bele trohnobe bolj razkrojile vzorce kot glive rjave trohnobe. Palmovina in les kavčukovca se po standardih (SIST EN 350-1 in SIST EN 460) za določitev naravne odpornosti uvrščata med neodporne drevesne vrste. Zaradi naravne odpornosti na glive bele trohnobe je les kokosove palme in kavčukovca primeren za uporabo v 2.in 3. razredu ogroženosti. Natural durability of palm (Cocos nucifera) and rubber tree (Hevea brasiliensis) wood against wood decay fungi from our geographical area was researched. The natural durability was proven with a mini block test method. The test showed that the white rot fungi were more successful in decomposing the specimens than the brown rot fungi. According to the natural durability standards (SIST EN 350-1 and SIST 460) the palm and rubber wood classify as non-durable species. Palm and rubber wood are suitable for use in 2nd and 3rd class of endangerment because of the natural durability.

Kostanjevino uvrščamo med najbolj naravno odporne slovenske lesne vrste. V literaturi zasledimo, da je najpomembnejši dejavnik naravne odpornosti kostanjevine vsebnost velikega deleža ekstraktivnih snovi. Želeli smo raziskati, kako na naravno odpornost kostanjevine vplivajo ekstraktivi in kakšen je njihov delež. Izdelali smo vzorce iz jedrovine pravega kostanja, izprali ekstraktive s 3 različnimi topili in vzorce izpostavili 5 glivam razkrojevalkam lesa: Gloeophyllum trabeum, Antrodia vaillantii, Pleurotus ostreatus, Trametes versicolor in Stereum hirsutum. Glivam razkrojevalkam smo izpostavili tudi neekstrahirane vzorce in kontrolne vzorce bukovine ter smrekovine. Izgubo mase po 12 tednih smo določili gravimetrično. Ugotovili smo, da se odpornost vzorcev jedrovine pravega kostanja proti glivam z delnim izpiranjem ekstraktivov bistveno ne zniža. Naravna odpornost je po ekstrakciji nekoliko slabša, vendar povezana z vsebnostjo ekstraktivov. Tudi ekstrahirana jedrovina pravega kostanja je dobro odporna proti glivam, neekstrahirano pa lahko uvrstimo v najvišji odpornostni razred (izguba mase okoli 1 %). Sweet chestnut wood is considered as one of the most durable Slovenian domestic wood species. There are several reports that the most important factor influencing wood durability are extractives. To find out if sweet chestnut wood durability is based on extractives and their contents, specimens were extracted and exposed to 5 different fungal species: Gloeophyllum trabeum, Antrodia vaillantii, Pleurotus ostreatus, Trametes versicolor and Stereum hirsutum. A part of specimens was extracted with soxhlet extraction with 3 different solvents. Fungal decay was determined gravimetrically after 12 weeks of exposure. In parallel, Norway spruce and beech wood samples were exposed to the wood decay fungi as well. Our results indicate that influence of extractives on wood durability is important although natural durability of sweet chestnut heartwood specimens after extraction is not significantly lowered. It can be resolved that natural durability of non-extracted sweet chestnut heartwood can be classified as very durable against fungal decay (mass loss lower than 1 %).