Important Wood Species Research Articles

Transcriptome analysis reveals the accelerated expression of genes related to photosynthesis and chlorophyll biosynthesis contribution to shade-tolerant in Phoebe bournei

BackgroundPhoebe bournei (P. bournei) is an important and endemic wood species in China. However, the plantation, nursing, and preservation of P. bournei are often affected by light. To investigate its physiological changes and molecular mechanism of low light tolerance, two-year-old P. bournei seedlings were subjected to different shading conditions. With the increase of light intensity in the shade, the leaf color of P. bournei seedlings became darkened, the aboveground/underground biomass significantly increased, the content of chlorophyll increased and the net photosynthetic rate significantly increased.Resultsde novo transcriptome analysis showed that 724 and 3,248 genes were differentially expressed due to low light intensity at T1 (35% light exposure) and T2 (10% light exposure), respectively, when compared to the controls. Furthermore, the differentially expressed genes (DEGs) were implicated in photosynthesis, nitrogen metabolism, plant hormone signal transduction, biosynthesis of secondary metabolites, and protein processing in the endoplasmic reticulum by functional enrichment analysis. Moreover, the expression of HSP, CAB, HEMA1, GSA, DVR, MYB, bHLH, PORA, CAO, GLK, and photosystem I and II complex-related genes significantly increased after low light exposure at T2 and T1.ConclusionsThe present study suggests that the rapid growth of P. bournei seedlings under shading conditions may be the result of the accelerated expression of genes related to photosynthesis and chlorophyll biosynthesis, which enable plants to maintain a high photosynthesis rate even under low light conditions.

Lignans dramatically enhance the resistance of Fraxinus velutina Torr. by adjusting the dominant bacterium group of Agrilus planipennis Fairmaire

Velvet ash (Fraxinus velutina Torr.) is an important wood and ornamental tree species. Emerald ash borer (EAB), Agrilus planipennis Fairmaire, is a major wood borer of velvet ash. The aim of this study was to identify the secondary metabolites of velvet ash involved in regulating the dominant bacterium group of EAB. The amount of lignans in the phloem of infested trees had increased by 290.96% because of A. planipennis infection. The addition of lignans to the artificial diet significantly reduced the weight of the larvae and decreased the dominant bacterial group in the larval midgut, such as Pseudomonadaceae, Xanthomonadaceae, and Enterobacteriaceae. The FvPLR1, a key gene for lignan synthesis, was obtained based on the phloem transcriptome of velvet ash. The expression of FvPLR1 in the phloem of the infested tree was significantly higher than that in the noninfested tree. Meanwhile, FvPLR1 silenced by virus-induced gene silencing showed that its expression level and the lignan content were decreased by 69.91% and 31.65%, respectively. Interestingly, silencing FvPLR1 induced alterations in the dominant bacteria group in the larvae, with the reverse trend in the lignan-fed treatment. The evidence showed that FvPLR1 was a positive regulator. The increasing synthesis of lignans leads to resistance improvement in velvet ash, which will provide comprehensive insights into the tree defense system to wood borer infestation. © 2021 Society of Chemical Industry.

Effects of artificial weathering on the color, gloss, adhesion, and pendulum hardness of UV system parquet varnish applied to doussie (Afzelia africana) wood

An important wood species in the furniture and parquet industry today is “doussie” wood. In this study, the effects of artificial weathering on ultraviolet-cured varnish (3 coats and 5 coats) applied to doussie (Afzelia africana) wood were investigated. The samples of the UV system cured varnishes were exposed to aging effects for 252 h and 504 h via an UV-A 340 nm lamp. The coated specimens were exposed to UV-A 340 nm fluorescent lamp in a QUV accelerated weathering tester for 252 h and 504 h. The surface adhesion strength, color (L*, a*, b*, ∆E*, ∆L*, ∆a*, and ∆b*) parameters, pendulum hardness, and glossiness (parallel (//) and perpendicular (⊥) at 20°, 60°, and 85°) of UV varnishes coated samples were quantified before and after weathering. According to the results, while the a* value increased, the adhesion, L*, b*, and glossiness values decreased with aging. As a result, it was concluded that doussie wood can be used in the production of flooring with UV-cured varnish.

Studies into Fungal Decay of Wood In Ground Contact—Part 1: The Influence of Water-Holding Capacity, Moisture Content, and Temperature of Soil Substrates on Fungal Decay of Selected Timbers

This article presents the results from two separate studies investigating the decay of wood in ground contact using adapted versions of laboratory-based terrestrial microcosm (TMC) tests according to CEN/TS 15083-2:2005. The first study (A) sought to isolate the effect of soil water-holding capacity (WHCsoil [%]) and soil moisture content (MCsoil [%WHCsoil]) on the decay of five commercially important wood species; European beech (Fagus sylvatica), English oak heartwood (Quercus robur), Norway spruce (Picea abies), Douglas-fir heartwood (Pseudotsuga menziesii), and Scots pine sapwood (Pinus sylvestris), while keeping soil temperature (Tsoil) constant. Combinations of soil mixtures with WHCsoil of 30%, 60%, and 90%, and MCsoil of 30%, 70%, and 95%WHCsoil were utilized. A general trend showed higher wood decay, measured in oven-dry mass loss (MLwood [%]), for specimens of all species incubated in soils with WHCsoil of 60% and 90% compared to 30%. Furthermore, drier soils (MCsoil of 30 and 70%WHCsoil) showed higher MLwood compared to wetter soils (95%WHCsoil). The second study (B) built on the first’s findings, and sought to isolate the effect of Tsoil and MCsoil on the decay of European beech wood, while keeping WHCsoil constant. The study used constant incubation temperature intervals (Tsoil), 5–40 °C, and alternating intervals of 10/20, 10/30, and 20/30 °C. A general trend showed drier MCsoil (60%WHCsoil), and Tsoil of 20–40 °C, delivered high wood decay (MLwood > 20%). Higher MCsoil (90%WHCsoil) and Tsoil of 5–10 °C, delivered low wood decay (MLwood < 5%). Alternating Tsoil generally delivered less MLwood compared to their mean constant Tsoil counterparts (15, 20, 25 °C). The results suggest that differences in wood species and inoculum potential (WHCsoil) between sites, as well as changes in MCsoil and Tsoil attributed to daily and seasonal weather patterns can influence in-ground wood decay rate.

Mechanical performance of Scots pine wood from northwestern Poland – A case study

Scots pine is one of the most commercially important wood species in Europe. This study assessed the potential usefulness of pinewood from the Noteć Forest for construction purposes by evaluating its mechanical properties and investigating the influence of the site conditions on the pinewood performance. Additionally, the variability of the mechanical properties from the bark to the pith was analyzed. The results showed that the properties of pinewood varied significantly within the Noteć Forest despite similar growing conditions, which may be a result of genetic variation. Wood from Sowia Góra had the greatest density (566 kg/m3) and excellent mechanical performance (compressive strength of 64 MPa), while wood from Zamyślin exhibited the lowest density (526 kg/m3) and a lower compressive strength (54 MPa). Comparison of the properties of the pinewoods from various locations indicated that the general conditions in the forest stand, however crucial for tree growth, were not the only determinants of wood performance. The results also showed high variability in density and mechanical properties between juvenile and mature wood in all the examined trees. Overall, pinewood from the poor habitats of the Noteć Forest could be a useful raw material for various industrial purposes.

Effect of canopy cover on development of cedar (<i>Cedrela fissilis</i>) and aspects of damage caused by <i>Hypsipyla grandella</i> in agroforestry system

Cedrela fissilis (Vell.) is an important wood species, native to South America. It is appreciated for its physical characteristics and, therefore, its native specimens are overexploited.Commercial cultivation initiatives have been continuously flawed as a result of the damage caused by mahogany shoot borer Hypsipyla grandella (Zeller, 1848).Planting under shaded sites has been one of the management methods used to reduce insect attacks. However, the reason why mahogany shoot borer does not attack shaded plants as often is still unknown. Therefore, the aim of this research was to find cultivation parameters that could combine proper plant development and low rate ofattacks by Hypsipyla grandella.For this purpose, increases in height and shoot diameter of cedar seedlings, planted in agroforestry systems, were monitored for the two first years. Three canopy cover rates, namely, 0-20%, 20-40% and 40-60%, were tested for plant development andfrequency of attacks byHypsipyla grandella. The adult population of the insect was monitored with semiochemicals throughout the experimental period, and two pheromonal blends and one food bait were tested. Field results showed that one of the pheromone blends was efficient in identifying small variations in the population of adult specimens. Regarding to the plant development, the treatment with the highest cover rate showed the lowest parameters compared to the intermediate cover. The frequency of attacks byHypsipyla grandella was greater in the treatment with the lowest cover (0-20%).The results suggest that in canopy cover, ranging from 20 to 40%, good rates of initial development of plants can be combined with low frequency of attack by Hypsipyla grandella.

Comparison of Birch and Beech Wood in Terms of Economic and Technological Properties for Plywood Manufacturing

The aim of this study was to investigate the use of birch wood, one of the most important wood species used in the plywood industry, especially in Europe, the Nordic countries, Poland, Belarus and Russia as an alternative to beech wood. For this purpose, comparison was made of their economic and technological properties. In five-ply plywood manufacturing, beech (Fagus orientalis Lipsky) and birch (Betula pendula) veneer sheets were used with melamine urea formaldehyde (MUF) and urea formaldehyde (UF) resins. Some mechanical properties such as shear strength, bending strength and modulus of elasticity of plywood panels were conducted according to EN 314-1 and EN 310, respectively. Mean mechanical strength obtained for birch plywood panels was quite above the limit values specified in the related standards. When taking into consideration the annual increment of beech and birch trees in 1 ha and the time they need to reach suitable diameters for the manufacturing of rotary cut veneers, it was calculated that birch trees provide 2.46 times more physical harvesting than beech trees.

Relative humidity versus moisture content relationship for several commercial wood species and its potential effect on flame spread

SummaryRecently, measured flame spread indices on commercial wood species tested per ASTM E84 were found to be lower than previously published data. One reason for this may be that the hygrothermal conditioning of the red oak calibrant required by the test standards for measuring flame spread was changed between 1973 and 1981. This paper examines how much variability there is in the moisture content of commercially important wood species at 50% relative humidity by collecting water vapor sorption isotherms. Additionally, the effect of moisture content on the flame spread was evaluated after conducting 14 tests with eastern white pine in accordance with CAN/ULC‐S102 and four in accordance with ASTM E84 at four commercial test laboratories. For the sorption isotherms, it was found that the moisture contents at 50% relative humidity ranged from 6.8% to 11.4% moisture content and depended on the species and whether the specimens had been conditioned in absorption or desorption. The flame spread indices, as measured as different laboratories, also varied from 37% at 10.4% reported moisture content to 200% at 6.5% reported moisture content. The findings suggest that the wood moisture content and conditioning requirements of the standards are important test variables that affect the flame spread results.

Effect of Density and Propagation Length on Ultrasonic Longitudinal Wave Velocity in Some Important Wood Species Grown in Turkey

In solids, density is an important factor that determines lots of properties such as mechanic behavior. Mechanic properties of materials can be determined by static and dynamic tests. Ultrasonic measurements are one of the non-destructive test methods and are being applied to lots of field for determination of wide range of properties. When literature in wood science reviewed, it’s seen that researches did not make a consensus on the effect of density on ultrasonic wave velocity. Also, propagation length is another issue that has close relations with ultrasonic waves. From this point of view, effects of density and propagation length on ultrasonic longitudinal wave in Oriental beech, Scots pine, Black pine and Turkish red pine woods were investigated in this study. 20x20 cross-cut and 20, 30 and 40mm L direction samples were used to perform measurements. All samples acclimatized at 20±1 °C temperature and 65% relative humidity. Then, ultrasonic measurements performed using OLYMPUS EPOCH 650 flaw detector and 2.25MHz contact type transducers. According to the results, MC of the samples were calculated around 12% and up to 25.49% increase in velocity observed when sample length increased from 20mm to 40mm. Coefficients of determination between density and velocity were ranged from 0.78 to 0.94. Therefore, it’s concluded that both propagation length and density have positive effect on ultrasonic wave velocity in these woods.

ANÁLISIS DE DIMENSIONES DASOMÉTRICAS Y PORCENTAJE DEL ATAQUE DE Hysipyla grandella Zeller EN Cedrela odorata L.


 
 
 Cedrela odorata es la segunda especie maderable más importante en Mesoamérica, por la alta calidad de su madera. En México, la situación actual que guardan sus poblaciones en toda su área de distribución es incierta. El objetivo del presente estudio fue determinar las condiciones de las poblaciones de cedro en 15 estados de la república mexicana y 67 sitios, con respecto al análisis de las dimensiones dasométricas y porcentaje del ataque de Hysipyla grandella. Los datos registrados fueron número de árbol, coordenadas geográficas, nombre del municipio, altitud, diámetro normal, altura total, altura de fuste, presencia o ausencia de ataque por insecto barrenador, así como las características del sitio. Sus coordenadas fueron registradas mediante GPS e incorporadas al ambiente de Sistema de Información Geográfica ArcView 3.2. ESRI. Los resultados indican que las poblaciones naturales distribuidas en el norte del país están muy reducidas, o en lugares inaccesibles. En el sureste, la especie ya no existe en condiciones naturales; hay árboles en áreas de traspatio, zonas urbanas y plantaciones comerciales. El análisis estadístico de las variables dasométricas reveló diferencias significativas (p<0.05) entre municipios dentro de los estados y entre estados. El porcentaje promedio a nivel nacional de la presencia de H. grandella fue de 80.5.
 
 

Comparison of Reliable Reference Genes Following Different Hormone Treatments by Various Algorithms for qRT-PCR Analysis of Metasequoia.

Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is the most sensitive technique for evaluating gene expression levels. Choosing appropriate reference genes for normalizing target gene expression is important for verifying expression changes. Metasequoia is a high-quality and economically important wood species. However, few systematic studies have examined reference genes in Metasequoia. Here, the expression stability of 14 candidate reference genes in different tissues and following different hormone treatments were analyzed using six algorithms. Candidate reference genes were used to normalize the expression pattern of FLOWERING LOCUS T and pyrabactin resistance-like 8. Analysis using the GrayNorm algorithm showed that ACT2 (Actin 2), HIS (histone superfamily protein H3) and TATA (TATA binding protein) were stably expressed in different tissues. ACT2, EF1α (elongation factor-1 alpha) and HIS were optimal for leaves treated with the flowering induction hormone solution, while Cpn60β (60-kDa chaperonin β-subunit), GAPDH (glyceraldehyde-3-phosphate dehydrogenase) and HIS were the best reference genes for treated buds. EF1α, HIS and TATA were useful reference genes for accurate normalization in abscisic acid-response signaling. Our results emphasize the importance of validating reference genes for qRT-PCR analysis in Metasequoia. To avoid errors, suitable reference genes should be used for different tissues and hormone treatments to increase normalization accuracy. Our study provides a foundation for reference gene normalization when analyzing gene expression in Metasequoia.

Preservation of sweet chestnut genetic resources (Castanea sativa Mill.) against attack by chestnut gall wasp (Dryocosmus kuriphilus Yasumatsu, 1951)

European sweet chestnut (Castanea sativa Mill.) is one of the most important wood species due to its environmental and economic role in many agro-forestry systems. Chestnut gall wasp (Dryocosmus kuriphilus Yasumatsu, 1951) is currently the most dangerous pest of sweet chestnut, including in Slovenia. Attack on vegetative buds (in which the eggs are deposited and on which galls are subsequently formed) disturbs the growth of shoots and reduces the yield. In the event of a strong attack, the tree can weaken and decay, which is already noticeable on the ground in Slovenia, especially in terms of the monitored genetic resources of the chestnut tree. Following Japanese experience, European countries are increasingly choosing biological control of chestnut gall wasp with the torymid wasp (Torymus sinensis Kamijo, 1982). Micropropagation is a way of ensuring effective preservation and reproduction while optimizing all phases of work. In the micropropagation of Slovenian sweet chestnut genetic resources, problems arise in the rooting phase.

Performance of Bark Beetle Damaged Norway Spruce Wood Against Water and Fungal Decay

Norway spruce is one of the most important wood species in Central Europe. Unfortunately, bark beetles have prominently attacked spruce trees. Bark beetles colonize wood in symbiosis with ophiostomatoid fungi, which is visible in prominent blue staining. This reduces the commercial value of the infested wood. The relevant properties of blue stained wood were therefore determined: bending and compression strength, sorption properties, DVS analysis, water uptake, and durability against wood decay fungi. This information was applied in the Meyer-Veltrup model for assessment of material resistance. Scanning electron microscopy analysis confirmed severe infestation of blue stained wood, which was also evident from the color of the specimens. The mechanical properties were almost unaffected, as were the sorption properties. However, the durability and water exclusion efficacy of blue stained wood were considerably decreased, which indicates that decay can be expected to appear faster on blue stained wood than on control-untreated wood specimens.

Variability of morphometrical characteristics of needles at a clonal plantation of plus trees of scots pine (Pinus sylvestris L.)

The formation of plus trees assortment for seed orchards is one of the most difficult problems of contemporary forest breeding. This problem is related to the risk of inbreeding depression of the seed progeny of plus trees, which do not have any defense mechanism against self-pollination. Economically, the Scots pine is one of the most important wood species. Diverse characteristics of its needles make a subject for multidisciplinary research. Needle size is accepted as an indirect indicator of growth pine energy. Our research was focused on selection valuation of Scots pine plus trees by morphometric features of needles. Plus trees are represented by their clones in first-order seed orchards in the Nizhny Novgorod region. When collecting the source material, the elimination of differentiating effects of environmental factors and time factors was ensured. The dissimilarity of plus trees at a wide range of signs was manifested to different degrees. Because the heterogeneity of the assortment composition of the seed orchard in question was formed against the background of the aligned environmental conditions, there was every reason to consider it as being caused largely by hereditary factors. It was confirmed by the results of ANOVA. The predominant influence of distinctions between ortets was established. The influence of distinctions between the ramets was revealed – that was comparable to the residual variance. Pronounced heterogeneity of the composition and its genetic determinism set up conditions for effective multivariate comparisons of plus trees. Factor analysis formed its integrated independent variables from a common set of morphological parameters of needles. They are used in cluster analysis along with the original signs. Cluster analysis revealed in the seed orchards plus trees that are to the greatest extent different from the others. They can be combined with all the other plus trees in cross-breeding schemes to achieve the heterosis effect and to eliminate the risk of inbreeding depression.

Saccharification of lignocellulosic biomasses via ionic liquid pretreatment

The current work focuses on the pretreatment efficiency of ILs combined with heat for woody biomass consisting of spruce, birch and pine as well as winter wheat straw. The latter was investigated as a comparison and with the aim to enhance its digestibility during enzymatic hydrolysis whereby the influence of IL-treatment to cellulose resistance for hydrolysis was investigated. Considering the wood species, the most common and industrially important wood species in Northern Europe were chosen in the present work and the goal was to obtain fermentable sugars and their degradation product, i.e. 5-hydroxymethylfurfural (5-HMF), which is known valuable platform chemical. Further, the differences in the yields of IL-obtainable carbohydrates between these species were studied. The highest sugar yields were obtained to glucose in the case of spruce and arabinose in the case of pine sapwood, 12.07 and 7.72mmol/L, respectively. The highest 5-HMF yield was obtained for spruce heartwood (9.18mmol/L) with longer treatment time, such as 100h. However, regarding woody biomass, the present work was focused more on the study and analysis of the IL-containing liquid part, wood hydrolysate, after IL-treatment aiming to answer the analysis challenges related to this fraction.

Some orthotropic mechanical properties of Sessile oak (Quercus petrea) as influenced by moisture content

In this study, the influence of moisture content on some orthotropic mechanical properties of sessile oak which is one of the most important wood species grown in Turkey and common in the furniture industry have been investigated. The properties studied include Young’s modulus, Poisson’s ratios and compression strength of oak wood in three anatomical directions. These properties are important input parameters for three dimensional modeling of mechanical behavior in advanced computer programs such as finite elements. The samples which were approximately 20 x 20 x 60 mm in dimensions were conditioned at 20 °C and 50, 65, 85, 95 % relative humidity conditions for 6-8 weeks and subjected to compression tests in order to determine elastic and strength properties. Results indicate that properties investigated significantly differ among all anatomical directions. Young’s modulus ranged from 10305 to 6984 N/mm 2 in L direction, from 2032 to 1132 N/mm 2 in R direction and from 1208 to 715 in T direction. Compression strength varied between 48.5 and 25.5 N/mm 2 in L direction, 16.45 and 9.60 MPa in R direction, and 10.2 and 7.1 in T direction. Poisson’s ratios are found to be in between 0.061 and 0.7. Results indicated that all properties of the samples tested were strongly affected by moisture content.

Performance of copper azole treated softwoods exposed to marine borers

Wooden material has been used for shipbuilding and structural purposes in the marine environment since ancient times. Wood being used in the sea water can be damaged by marine wood boring organisms, which can turn marine wooden structures unserviceable with great economic cost. Using naturally durable species and preservative treated wood can increase the service life of wooden maritime structures and avoid or minimise the damages caused by marine borers. In this study, Scots pine (Pinus sylvestris), Black pine (Pinus nigra) and Turkish fir (Abies bornmulleriana) naturally grown and economically important wood species in Turkey were treated with copper-azole and evaluated in marine trials for 7 and 14 months in the Western Black Sea region. In this experiment, Teredo navalis was the only teredinid species identified. Copper-azole treated fir and Scots pine specimens suffered no attack, after 7 and 14 months exposure, except four panels which suffered minor damage. However, copper-azole treated Black pine panels were moderately damaged, and all of the control panels of the softwoods were strongly attacked. The average largest shell diameter was found to be 4,79 mm in Scots pine, while the longest pallets (4,71 mm) was found in Black pine. All untreated test panels scored an average of 4 (heavily attacked) after a 14 month period. The cellulose ratio of Black pine decreased from 56 % to 50 %, and the holo-cellulose ratio from 76 % to 71 %. The treated samples showed resistance against marine borers although the copper (cu) leaching was high during the 14 months exposure underwater.

Rapid Assessment of Surface Color of Chinese Fir and Eucalyptus Wood by near Infrared Spectroscopy

Chinese fir and eucalyptus are the important plantation wood species in China. Wood color is a property that can reflect aesthetic features of wood and increase the perceived quality of wood. The color parameters of the two woods and the ability of near infrared (NIR) spectroscopy to assess the color parameters were investigated in this study. The results shown the L*, a* and b* values of Chinese fir were 51.91~73.33, 6.26~12.94 and 20.36~32.04 and that of eucalyptus were 42.30~62.44, 8.48~62.44 and 15.07~25.15 respectively. The excellent related coefficients (r) and lower square error of calibration (SEC) illustrated NIR spectroscopy coupled with multivariate data analysis has ability to rapidly predict the L*, a* and b* values of the two wood species. The use of reduced spectral range has little effect on the quality of PLS models allowing the use of inexpensive and portable spectrometers with lower wavelength region to rapidly assess wood surface color.

Bioincising of Norway spruce wood using wood inhabiting fungi

Norway spruce (Picea abies) is one of the most important wood species in Europe. Its wood is frequently used for commercial applications. More extensive use is limited due to insufficient durability and low permeability. Particularly heartwood is difficult to impregnate. The aim of this preliminary study was to use wood inhabiting fungi for pre-treatment of spruce wood prior to impregnation. Therefore Norway spruce wood specimens (2.0 × 2.0 × 5.0 cm) with end sealed axial surfaces were exposed to one brown rot (Antrodia vaillantii) one white rot (Hypoxylon fragiforme) and one blue stain fungus (Sclerophoma pithyophila) for periods between 14 and 60 days. Afterward mass loss, compression strength, uptake of preservative solutions and retention were determined. The results showed that fungal pre-treatment increased the uptakes of preservative solutions. Among tested fungi, H. fragiforme was found particularly effective. The highest loadings were determined after 30 days of exposure. However, prolonged pre-treatment periods did not improve the impregnability of the specimens but resulted in more prominent losses of mechanical properties.

Determination of Screw and Nail Withdrawal Resistance of Some Important Wood Species

In this study, screw and nail withdrawal resistance of fir (Abies nordmanniana), oak (Quercus robur L.) black pine (Pinus nigra Arnold) and Stone pine (Pinus pinea L.) wood were determined and compared. The data represent the testing of withdrawal resistance of three types of screws as smart, serrated and conventional and common nails. The specimens were prepared according to TS 6094 standards. The dimensions of the specimens were 5x5x15cm and for all of the directions. Moreover, the specimens were conditioned at ambient room temperature and 65+/-2% relative humidity. The screws and nails were installed according to ASTM-D 1761 standards. Nail dimensions were 2.5mm diameter and 50 mm length, conventional screws were 4x50mm, serrated screws were 4x45mm and smart screws were 4x50mm. Results show that the maximum screw withdrawal resistance value was found in Stone pine for the serrated screw. There were no significant differences between Stone pine and oak regarding screw withdrawal resistance values. Conventional screw yielded the maximum screw withdrawal resistance value in oak, followed by Stone pine, black pine and fir. Oak wood showed the maximum screw withdrawal resistance value for the smart screw, followed by Stone pine, black pine, and fir. Oak wood showed higher nail withdrawal resistances than softwood species. It was also determined that oak shows the maximum nail withdrawal resistance in all types. The nail withdrawal resistances at the longitudinal direction are lower with respect to radial and tangential directions.