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Nature has been said to have relaxing effects on human. In today’s world, people’s life takes place mostly indoors so it is essential to seek relaxing effects also indoors. Decorative wood surfaces may bring those relaxing effects of nature to an indoor environment. This research focuses on researching the restorative effect of wooden surfaces through people’s preferences and the abilities of wooden surfaces. In this research, people’s preferences between different wooden surfaces were compared with the use of haptic and visual sensations. All the surfaces were lightly sanded to minimize the effects of pro-cessing and to concentrate merely on the comparison of different materials. The selected surface materials were conifer glulam, birch glulam, birch plywood, conifer plywood, MDF-board (Medium Density Fibreboard) and OSB-board (Oriented Strand Board). The study was divided into three sec-tions: the first section concentrated on people’s preferences towards wooden surfaces only with haptic sensations, the second part included only visual sensations and the third part included both haptic and visual sensations. The third section also included an open question for participants about the potential use of each wood material. Some of the participants also took part in a stress test during the third section. The stress test aimed to examine whether the participants’ heart rate and blood pressure lowered as they experienced the haptic and visual effects of wood material and if there were differ-ences between different materials. In the preference study people were instructed to rate the descriptiveness of different adjectives with all the wooden samples on a scale of 1–7 (1 very little, 7 very much). The three sections of the study made it possible to compare participants’ haptic and visual sensations. The visual sensations were observed to have more dominant effect than haptic sensations on the participants’ preferences. The visually most preferred wood materials were also found the most potential use for. These materials were instructed to be used in places they were seen whereas the less preferred materials were instructed to be used in hidden structures and to remain unseen. Both the heart rate and blood pressure lowered from the start of the test with all the materials except with OSB-board that caused a little rise of heart rate and blood pressure.

In recent years objectives to increase fuelwood usage have created a need to develop new re-mote sensing based methods to map fuelwood reserves. Laser scanning (LiDAR) is a remote sensing method which has been used in traditional forest inventories on large forest areas. These inventories have mainly concentrated on the stem volume instead of the total tree bio-mass. Former studies concerning fuelwood inventory accuracy have been made on a sample plot level. The aim of this study was to determine the precision of LiDAR based fuelwood inventory on a forest stand level. Wood stem volume and biomass estimates were produced by using two dif-ferent methods: point cloud and digital terrain model. The estimates were compared with field inventory results and results from the multi-source National Forest Inventory. Of the two compared methods the point cloud method was found to be more accurate than the method based on digital terrain model. When the point cloud was used, the accuracy (RMSE %) of the most important fuelwood estimates were following: waste wood vol-ume 37.4 %, branch biomass 21.8 % and stump biomass 18.6 %. The study indicates that re-sults got by laser scanning are on similar level as results got with traditional standwise inventory. This study concentrated only to predict the amount of fuelwood on the forest stand level. The suitability of the stand for fuelwood harvesting was not estimated. In order to utilize LiDAR-based fuelwood inventory for wood acquisition in forest industry, methods to estimate the suita-bility of the stand for harvesting need to be developed.

There is need for information about stands and their future development in forest planning decision making. This information is collected by inventories. In general inventory is repeated with some before-hand set intervals, irrespective of the method. Between inventories information is updated with growth models. Both inventory and using of growth models causes errors in forest planning results, for example in management options. Erroneous predictions can lead to wrong conclusions and inoptimal decisions. If the optimal result is known, economical losses caused by wrong conclusions can be described with so called inoptimality losses. The aim of this study was to answer the question how long forest inventory information, updated with growth models, can be used in forest planning purposes. Study approach was economical, so evaluation of information`s usefulness was based on inoptimality losses which arise when development of the stand is predicted incorrectly with growth models. The study material included 99 stands. Their development was simulated with the SIMO software for 60 years from present. In the 60 years period influencies of growth prediction errors were studied with inventory periods which lengths were 5, 10, 15, 20, 30 and 60 years. It was assumed that new error-free forest inventory information was received in the beginning of each of the inventory periods. In order to study effects of different inventory periods, it was assumed that the growth models were able to predict the true development of stands. Erroneous developments were yielded with error model which was developed for this study and added to the growth models. Inoptimality losses were calculated with the information derived from the optimization of stands` true and erroneous developments. Inoptimality losses increased when the inventory period became longer. Absolute inoptimality loss was approximately 230 eur/ha when the inventory period was 5 years and approximately 860 eur/ha when the inventory period was 60 years. Relative inoptimality loss was 3,3 % when the inventory period was 5 years and 11,6 % when the inventory period was 60 years. The average inoptimality losses were different between different development classes, site classes and main tree species. Study results show that the length of the updating period has an effect on the developing economical losses. It seems also that the inventory period should be different for example in different development classes. However, it is difficult to specify the optimal updating period because total losses are a sum of losses of inventory errors, losses of growth prediction errors and losses caused by other uncertainty sources. The effects of both inventory errors and growth prediction errors are different in different kinds of stands. So estimation of total losses and estimation of inoptimality losses caused by different error sources requires more research.

The purpose of this study was to find out the effect of different seed tree densities on natural regeneration and height development of pine (Pinus sylvestris) in Finnish Lapland. There was no soil preparation done in the stands. An additional aim was to find out the effects of understory vegetation on pine seedling establishment. The purpose of preparatory cutting is to prepare the stand for natural regeneration by enhancing the conditions for good seedling establishment and improve the seed production of the mature trees before the actual regeneration cutting. It also decreases the costs of regeneration in the low-productive and slow-growing forests in Finnish Lapland. The study was established in year 2004 on four different areas in Lapland. The replications were conducted for every area in the years 2005 and 2006.The period of measurement in every replication was 8 years. The examined seed tree densities were 50, 150, 250 stems per hectare and a non-thinned control that demonstrated the initial state of the stands. The data consisted of four hierarchical levels, which were area, replicate, treatment (seed tree densities) and experimental plot. The density model was a generalized mixed model and the height model a general linear model. The best result in seedling establishment was achieved in seed tree density of 50 and 150 stems per hectare, where the requirements for the density of the forest law (1200 seedlings ha-1) was reached in 4‒5 years after the preparation cutting. The amount of the seedlings at the end of the measurement period, did not on an average reach the recommended seedling densities (4000‒5000 seedlings ha-1). The seed tree density of 250 stems per hectare, did not reach either of these requirements for density. In the control plot, the average seedling density was 1500 seedlings per hectare at the end of the measurement period. The variables affecting seedling establishment were interactions between the see tree densities and time, thickness of the moss- and lichen cover and the coverage of lingonberry. Factors affecting the height development of pine seedlings were age of the seedling, interactions between seed-tree density and seedling age and the average density of the seedlings on the plot. Height increased clearly best when seed-tree density was 50 stems ha-1. There were no difference between densities 150 stems per hectare and control. The height development was slowest in the density of 250 stems per hectare.

Suomessa yleisesti puunkorjuussa käytössä olevassa tavaralajimenetelmässä hakkuukone katkoo rungon metsässä useisiin puutavaralajeihin käyttöpaikan vaatimusten mukaan. Puutavaralajien määrät ja dimensiot vaikuttavat kuormatraktorityön tehokkuuteen ja sitä kautta työn tuottavuuteen. Määrämitaltaan lyhyt puutavara ei täytä koneen koko kuormatilaa, mutta lyhyen puun käyttöä puoltaa sen hyödyt kaukokuljetuksessa ja loppukäyttöpaikalla. Kuitupuutavaran pituusvaihtelu vaikeuttaa tiiviin ja massaltaan täyden kuorman kuormaamista. Kahden kolmemetrisen nipun yhtäaikaisella kuljettamisella kuormatraktorin kuormatila voitaisiin hyödyntää paremmin, mikäli koneen ja maaperän kantavuus sallivat suuremman kuorman. Tutkimuksen tavoitteena oli selvittää kahden puutavaranipun yhtäaikaisen ajon edellytyksiä sekä sen vaikutuksia kuormatraktorityön ajanmenekkiin. Tutkimuksen ensimmäinen osio toteutettiin vertailevana aikatutkimuksena kolmella hakkuutyömaalla. Tutkittavia puutavaralajeja olivat kolmemetrinen havukuitupuu, vapaasti katkottu havukuitupuu, kolmemetrinen lehtikuitupuu, vapaasti katkottu lehtikuitupuu sekä mäntyparru. Kolmemetrisen kuitupuun ja parrun lähikuljetuksen tuottavuutta yhden- ja kahden nipun kuormana verrattiin muiden puutavaralajien lähikuljetuksen tuottavuuteen. Kahden nipun ajon tuottavuutta tutkittiin myös herkkyysanalyysin avulla siten, että analyysin pohjana käytettiin aikaisempien tutkimusten ajanmenekkimalleja. Mallien parametrejä muutettiin tämän työn aineiston perusteella ja työvaiheiden ajanmenekkikertoimia kahden nipun ajossa muutettiin. Tutkimuksen toinen osa oli haastattelututkimus metsäkonevalmistajille. Haastattelun tavoitteena oli saada neljältä konevalmistajalta arvio siitä, kuinka suuri osuus vuosina 2016–2020 rekisteröidyistä kuormatraktoreista on varustettavissa kahden puutavaranipun yhtäaikaiseen ajoon. Traficomin rekisteröintitietojen perusteella selvitettiin koneiden markkinaosuudet ja konevalmistajien arvioiden avulla muodostettiin kokonaiskuva nykypäivän kuormatraktorikaluston soveltuvuudesta kahden nipun yhtäaikaiseen ajoon. Haastateltavilta pyydettiin myös näkemyksiä siihen, mitä ominaisuuksia kuormatraktorilta vaaditaan, jotta kahden nipun ajo onnistuu. Kahden nipun ajotapa vähensi kuormaustuottavuutta sekä purkutuottavuutta. Kuormattuna-ajonopeus ei muuttunut eri kuormatyyppien välillä tai kuorman koon kasvaessa. Kuormakoko oli keskimäärin 1,8 kertainen kuin vastaavan puutavaralajin yhden nipun kuoman. Aineiston perusteella kahden nipun ajo oli tuottavampaa kuin yhden nipun ajo päätehakkuukohteilla. Harvennuksella yhden nipun ajo oli tuottavin ajotapa alle 300 metrin metsäkuljetusmatkoilla. Kahden nipun ja vapaasti katkotun kuitupuun ajanmenekkierot eivät olleet yhtä suuria. Päätehakkuilla kahden nipun ajo oli tuottavin ajotapa pitkillä metsäkuljetusmatkoilla. Neljän konevalmistajan arviot kahden nipun ajoon varustettavien koneiden määrästä vaihtelivat 60 ja 80 prosentin välillä. Markkinaosuuksiin suhteutettuna muodostettiin arvio, että 67 prosenttia viimeisen viiden vuoden aikana rekisteröidyistä koneista on varustettavissa kahden puutavaranipun yhtäaikaiseen kuljetukseen. Kahden nipun ajolle on kiinnostusta, sillä asiakkaille on uutta konetta ostaessa tärkeää, että sillä voidaan ajaa kahta nippua vähintäänkin satunnaisesti. Koneen tärkeimmät ominaisuudet kahden nipun ajoa varten ovat tarpeeksi pitkä kuormatila ja riittävä kantavuus. Muita tärkeitä ominaisuuksia kahden nipun ajoa varten ovat jatkoperä, tehokas kuormain ja tarpeeksi pitkä puomi, sekä kantavat telat joiden avulla vähennetään pintapainetta. Kuormatraktorityön tuottavuuteen vaikuttavat kuitenkin monet asiat, eikä kahden nipun ajo sovellu kaikkiin olosuhteisiin. Maaperän kantavuus voi muodostua esteeksi kahden nipun kuljetukselle. Toisaalta kahden nipun ajo vähentää ajokertojen määrää leimikolla, kun puuta kuljetetaan kerralla suurempi määrä. Kahden nipun ajon vaikutuksia maaperään olisi syytä tutkia jatkossa lisää.

In October 2013 the Finnish legislation for the ratings of vehicles was changed. This change enabled heavier vehicles to operate in Finland. The highest rating of vehicle combination is 76 tons and it requires nine axle. For eight axle vehicle combinations the mass is 68 tons and for seven axle 64 tons This reformation is taken to use especially in the raw material transportation such as timber. In this study the highest permitted masses weren’t reached in all observations, neither for vehicles nor vehicle combinations. On average the masses were reached in all observations except the four axle trucks. The average vehicle mass for them were 31977 kg. While the mass of the combination or a single vehicle increases the axle load remains the same or even decreases. The total mass devices for several axle. Fully loaded vehicle’s bogie masses didn’t differ from the not fully loaded. However the highest permitted bogie masses weren’t reached in all cases. Especially bogie masses of the vehicles without a loader were under permitted masses. In the study there was done some calculations for increasing the loading space. In these cases the highest permitted vehicle mass-es were reached. In most of the cases also the double axle masses were reached. The road wear of vehicle combinations is decreasing while the amount of axle is increasing. The ESAL (Equivalent Single Axis Load) reaches it highest point in the combined vehicle which total mass is 64 tons (6,87). The smallest stress is 76 tons combinations (3.33). The stress was higher for 3+5-type vehicles (4,64) than 4+4-type (4,52) in this study. The stress was bigger for the combinations with a loader. The effectivity of the transportation changed in the range 7663-9443 kg/ESAL and it decreased while the amount of axle increased. The difference between 68 tons vehicle combinations was small. The transportation costs decrease while the total masses increase. The biggest difference, on average with relation to 60 tons vehicle combination, is on 76 tons combination (-18,53%). For the 3+5-type combination the difference is -11,52% and for the 4+4-type combination -9,38%, so there is a difference between these two combinations. The average annual transportation increases while the total mass of the vehicle combinations mass is increasing. The growth is between 8 and 26%. The average costs for the comparison combine were 5,85 €/m3 and the annual transportation 27700 m3.

Reducing global carbon dioxide emissions is one of the main targets in the fight against climate change. Forests are important carbon pools and the arid regions of the world hold a great carbon sequestration potential. Dryland afforestation could play a considerable part in climate change mitigation. The aim of this study is to understand plantation forestry and the costs of afforestation work in arid and semi-arid regions. The main objective of the study is to estimate the establishment costs of 5.000-hectare irrigated forest plantation in Morocco, planned by the Finnish energy company St1. The plantation establishment costs are consisted of labor factors, such as preparing and mapping the cultivated area, fencing, seedling production, tillage, planting and aftercare, and other maintenance operation. The irrigation cost consist of developing the irrigation system, operation and maintenance costs and the price of desalinated seawater used in the plantation. The research timeframe was set to be from 0 to 5 years, assuming that this period covers the major cost factors of the plantation establishment. According to the results, the total establishment cost of the St1’s 5.000-hectare forest plantation, planned in Morocco, is estimated to be approximately EUR39 million and the cost per hectare around EUR7800. The total cost of cultivation is estimated to be about EUR18 million and the total cost of irrigation in the first four years are around EUR21 million.

Pruning of Scots pine is a traditional silvicultural method where branches are removed, usually up to 4–6 meters of height. Objective is to obtain better log and finally sawn timber quality. Pine branches fall off naturally as well but artificial pruning hastens the process of forming branchless sapwood. However, pruning of Scots pine has proven to be poorly profitable and is often described as silvicultural technique for active forest owners who do not set remarkable economical goals for their actions. Economic efficiency of pruning is weakened by the lack of quality-based pricing of timber whereupon forest owners or timber merchants do not get sufficient payment for their efforts. Highly developed x-ray log scanners at sawmills are capable of measuring log-internal quality at appropriate resolution. Measured information of log quality is utilized for log sorting at sawmills but it could also be used as the basis of pricing the timber. The aim of this thesis is to examine how pruning shows in log-internal quality which is measured by x-ray log scanner and what kind of differences arise between pruned and reference logs. The material for the thesis included 557 pruned and 111 reference logs which were harvested from a pine stand located in Ruovesi. The time elapsed from pruning was 33 years. The differences between pruned and reference logs were evaluated by quality attributes which were knottiness index, log top-end knottiness index, average knot cluster length, relative volume of largest knot and knot cluster, annual ring width and sapwood density. Finally, the quality differences between pruned and reference logs were inspected with predictions of sawn timber quality which were derived through knottiness index values. The internal quality of pruned proved to be better in every quality defining attribute. Statistical significance (p-value<0.001) between attribute means was found in average knot cluster length and in relative volume of knot as well as knot cluster. The predicted sawn timber quality distribution among the pruned A-graded logs, had 20% increase in U/S-quality and 2% decrease in VI-quality. The results of this thesis confirm the earlier findings that pruning of Scots pine is unsuitable at mesic pine stands and the selection of stands for pruning should be considered carefully. In case of the experimental stand, the sealing-off of pruned branches and the formation of knotless sapwood was still in progress while trees were harvested. In further studies, the effect of pruning on internal quality of timber should be considered with wider sample which consists of stands from divergent site types.

In this study, a quality assessment method based on sampling of primary laser inventory units (microsegments) was analysed. The accuracy of a laser inventory carried out in Kuhmo was analysed as a case study. Field sample plots were measured on the sampled microsegments in the Kuhmo inventory area. Two main questions were considered. Did the ALS based inventory meet the accuracy requirements set for the provider and how should a reliable, cost-efficient and independent quality assessment be undertaken. The agreement between control measurement and ALS based inventory was analysed in four ways: 1) The root mean squared errors (RMSEs) and bias were calculated. 2) Scatter plots with 95% confidence intervals were plotted and the placing of identity lines was checked. 3) Bland-Altman plots were drawn so that the mean difference of attributes between the control method and ALS-method was calculated and plotted against average value of attributes. 4) The tolerance limits were defined and combined with Bland-Altman plots. The RMSE values were compared to a reference study from which the accuracy requirements had been set to the service provider. The accuracy requirements in Kuhmo were achieved, however comparison of RMSE values proved to be difficult. Field control measurements are costly and time-consuming, but they are considered to be robust. However, control measurements might include errors, which are difficult to take into account. Using the Bland-Altman plots none of the compared methods are considered to be completely exact, so this offers a fair way to interpret results of assessment. The tolerance limits to be set on order combined with Bland-Altman plots were suggested to be taken in practise. In addition, bias should be calculated for total area. Some other approaches for quality control were briefly examined. No method was found to fulfil all the required demands of statistical reliability, cost-efficiency, time efficiency, simplicity and speed of implementation. Some benefits and shortcomings of the studied methods were discussed.

Pinus taeda is an important timber species both economically and ecologically. In past years there have been severe economic losses, as well as ecological disruption, due to epidemic outbreaks of Dendroctonus frontalis. Resin flow is the first line of defense within conifer species acting as both a physical and chemical barrier to invading pests. This study demonstrates the effectiveness of utilizing aggregation pheromones to attract Ips spp. bark beetles to Pinus taeda plantation stands in order to study the resin flow defense response mechanism. Individual trees were selected to be baited with aggregation pheromones. Trees in close proximity to the baited tree were labeled as monitor trees, and a control was established. Results of a general linear model for the aggregation pheromone attracting Ips spp. beetles indicate that there was a significant different (p<0.0001) between the baited and control trees. Using a repeated measures ANOVA, differences of resin flow exudation in Pinus taeda were considered among varying stand conditions (fertilizer, fire, anc control plots) during the induced Ips spp. bark beetle attack. This study illustrates that different stand conditions elicit more or less of a response of Ips spp. to the baited trees, however, site treatment did not significantly affect resin flow. We conclude that utilizing pheromones to attract Ips spp. bark beetles in an effective technique for studying the resin flow defense in conifers. From a management perspective, it is concerning to see differences in bark beetle activity amond different stand conditions while simultaneously seeing no difference in resin flow defense, making this an important aspect of integrated pest management study, and an area in need of further research.