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Background : Tree-related microhabitats (hereafter, “TreMs”) are key components of forest biodiversity but they are still poorly known in North American hardwood forests. The spatial patterns of living trees bearing TreMs (hereafter, “TreM-trees”) also remain to be determined. As logging practices can lead to a loss of TreM-trees and of their associated biodiversity, it is essential to identify the factors explaining TreM occurrence to better integrate them into forest management. We therefore inventoried TreMs in 4 0.5-ha survey strips in northern hardwood forests in Quebec, Canada, while recording the spatial location of each tree. Two strips were located in unmanaged old-growth forests, and 2 were in forests managed under selection cutting. All 4 stands were dominated by sugar maple (Acer saccharum Marsh.) and American beech (Fagus grandifolia Ehrn.). Beech bark disease, an exotic pathology, was observed in all the strips. Results : Large diameter at breast height and low tree vigor were the main characteristics explaining the presence of TreMs at the tree scale. TreM-trees presented slight spatial aggregation patterns. These aggregates, however, were not well-defined and were generally constituted by a large number of trees bearing few different types of TreMs. Two TreM classes (broken branch or top and woodpecker lodge) also presented a spatial aggregation. Logging practices had no significant effect on TreM occurrence. Beech bark disease increased the frequency of senescent beeches. The impact of this pathology on TreMs was however mitigated by the small size of infected trees and probably by the short time elapsed since its appearance. Conclusion : The factors explaining the presence and abundance of TreMs on trees has so far been little studied in North American hardwood forests. Our results highlight that TreM-tree characteristics in the surveyed forests are consistent with those of previous studies conducted in other forest types and regions (e.g., Europe

[ES] En el 2009 se estableció una red de 15 parcelas permanentes en una masa coetánea de Pinus halepensis Mill. en el MUP V154 “La Hunde y La Palomera” de Ayora (Valencia) con el fin de evaluar diferentes técnicas de gestión silvícola en esta especie. Se trata de un fustal de 60 años procedente de repoblación en el que se llevaron a cabo tratamientos de clara por lo bajo débil, clara baja fuerte, huroneo diamétrico y transformación a irregular. Cada tratamiento constó de tres repeticiones y, además, se fijaron tres parcelas testigo. El presente trabajo tiene el objetivo de analizar el efecto que estos primeros tratamientos y dos perturbaciones posteriores por viento y nieve (en 2010 y 2017) han tenido sobre el desarrollo de la masa estudiada. Para cada tratamiento, se han analizado las principales variables dasométricas y el nivel de regeneración y de cobertura de matorral. Se han vuelto a aplicar las cortas siguiendo la misma metodología, a fin de consolidar conclusiones en los próximos 10-20 años. Tras el análisis de los daños por los temporales, se ha concluido que las primeras intervenciones han mejorado la estabilidad del total de la masa, si bien las intervenciones más intensas comportan mayores riesgos de derribos en los años inmediatamente posteriores. Respecto a las características dasométricas, las diferencias entre los tratamientos de clara baja débil y fuerte se han demostrado marginales, y se ha observado que, a mayor intensidad de corta, mayor crecimiento corriente en diámetro medio. Además, se han detectado indicios de un sacrificio de producción en el tratamiento de huroneo, que no se produce en el tratamiento de irregular. Por otra parte, el tratamiento de huroneo es el que ha presentado mejores resultados en cuanto a regeneración, seguido del de transformación a irregular, que también cuenta con una importante presencia de Ulex parviflorus Pourr. Finalmente, ante la imposibilidad de replantear nuevas parcelas sobre el terreno y tras constatar la gr, [EN] In order to evaluate different silvicultural alternatives for even-aged stands of Pinus halepensis Mill. a network of 15 permanent plots was stablished in MUP V154 “La Hunde y La Palomera” (Ayora, Valencia). The stand was planted 60 years ago. Additionally to witness plots, two different thinning intensities, as well as two selection felling treatments with the aim to convert this stands to unevenaged structures, were carried out. The aim of this study is to analyse the effect of these treatments and the damage caused by two storms (in 2010 and 2017) in terms of main stand characteristics, natural regeneration and shrub coverage. By following the same methodology, the different treatments have been carried out for the second time, in order to consolidate conclusions in the next 10-20 years. After analysing the wind and snow damages, results show a noticeable improvement in crop stability 10 years after the fellings, even though the greater intensities imply a higher risk of windthrows the years immediately after the interventions. In regard to stand characteristics, the differences between both thinning methods have turned out to be minimal, and an evidence of a loss of yield by volume has been detected in the selection cutting treatment. Also, it concludes that the greater the intensity of felling, the larger the current increment of square mean diameter. On the other hand, the selection cutting treatment has shown the highest percentage of regeneration, followed by the transformation to uneven-aged stand treatment. Finally, facing the difficulties in locating new plots in the study area and after confirming the strong similarity between both thinning intensities, the low thinning regime has been substituted by preparatory fellings treatment before shelterwood regeneration system is applied at a later stage and with a final rotation age of 80 years. The results of this research, with all precaution until they can be confirmed in 10-20 years, allow a set of fir, [CA] L’any 2009 es va establir una xarxa de 15 parcel·les permanents en una massa coetània de Pinus halepensis Mill. en el MUP V154 “La Hunde i La Palomera” (Ayora, València) amb l’objectiu d’avaluar diferents tècniques de gestió selvícola en aquesta espècie. Es tracta d’un fustal de 60 anys procedent de repoblació en el que es van aplicar tractaments d’aclarida baixa dèbil, aclarida baixa forta, huroneig diamètric i transformació a irregular. Cada tractament constava de tres repeticions y, a més a més, es van establir 3 parcel·les control. El present treball té l’objectiu d’analitzar l’efecte que aquests primers tractaments i dos pertorbacions posteriors per vent i neu (2010 i 2017) han tingut sobre el desenvolupament de la massa estudiada. En cada tractament s’han analitzat les principals variables dasomètriques, el nivell de regeneració i la coberta de matoll. S’han tornat a aplicar les tallades seguint la mateixa metodologia per tal de consolidar conclusions en els pròxims 10-20 anys. Després d’analitzar els danys causats pels temporals, es conclou que les primeres intervencions han millorat l’estabilitat del total de la massa, si bé les intervencions més intenses impliquen majors riscos de caiguda d’arbres en els anys immediatament posteriors. En referència a les característiques dasomètriques, les diferencies entre els tractaments de clara baixa dèbil y forta s’han mostrat marginals, y s’ha observat que, a major intensitat de les intervencions, major creixement corrent en diàmetre mitjà. A més a més, s’han detectat indicis d’un sacrifici de producció en el tractament d’huroneig que no es produeixen en el tractament d’irregular. D’altra banda, pel que fa a la regeneració, el tractament d’huroneig es el que ha presentat els millors resultats, seguit de la transformació a irregular. En aquest últim cas, destaca l’elevada presencia de Ulex parviflorus Pourr. Finalment, davant la impossibilitat d’establir noves parcel·les sobre el terreny i després d’haver constata

[ES] En el 2009 se estableció una red de 15 parcelas permanentes en una masa coetánea de Pinus halepensis Mill. en el MUP V154 “La Hunde y La Palomera” de Ayora (Valencia) con el fin de evaluar diferentes técnicas de gestión silvícola en esta especie. Se trata de un fustal de 60 años procedente de repoblación en el que se llevaron a cabo tratamientos de clara por lo bajo débil, clara baja fuerte, huroneo diamétrico y transformación a irregular. Cada tratamiento constó de tres repeticiones y, además, se fijaron tres parcelas testigo. El presente trabajo tiene el objetivo de analizar el efecto que estos primeros tratamientos y dos perturbaciones posteriores por viento y nieve (en 2010 y 2017) han tenido sobre el desarrollo de la masa estudiada. Para cada tratamiento, se han analizado las principales variables dasométricas y el nivel de regeneración y de cobertura de matorral. Se han vuelto a aplicar las cortas siguiendo la misma metodología, a fin de consolidar conclusiones en los próximos 10-20 años. Tras el análisis de los daños por los temporales, se ha concluido que las primeras intervenciones han mejorado la estabilidad del total de la masa, si bien las intervenciones más intensas comportan mayores riesgos de derribos en los años inmediatamente posteriores. Respecto a las características dasométricas, las diferencias entre los tratamientos de clara baja débil y fuerte se han demostrado marginales, y se ha observado que, a mayor intensidad de corta, mayor crecimiento corriente en diámetro medio. Además, se han detectado indicios de un sacrificio de producción en el tratamiento de huroneo, que no se produce en el tratamiento de irregular. Por otra parte, el tratamiento de huroneo es el que ha presentado mejores resultados en cuanto a regeneración, seguido del de transformación a irregular, que también cuenta con una importante presencia de Ulex parviflorus Pourr. Finalmente, ante la imposibilidad de replantear nuevas parcelas sobre el terreno y tras constatar la gr, [EN] In order to evaluate different silvicultural alternatives for even-aged stands of Pinus halepensis Mill. a network of 15 permanent plots was stablished in MUP V154 “La Hunde y La Palomera” (Ayora, Valencia). The stand was planted 60 years ago. Additionally to witness plots, two different thinning intensities, as well as two selection felling treatments with the aim to convert this stands to unevenaged structures, were carried out. The aim of this study is to analyse the effect of these treatments and the damage caused by two storms (in 2010 and 2017) in terms of main stand characteristics, natural regeneration and shrub coverage. By following the same methodology, the different treatments have been carried out for the second time, in order to consolidate conclusions in the next 10-20 years. After analysing the wind and snow damages, results show a noticeable improvement in crop stability 10 years after the fellings, even though the greater intensities imply a higher risk of windthrows the years immediately after the interventions. In regard to stand characteristics, the differences between both thinning methods have turned out to be minimal, and an evidence of a loss of yield by volume has been detected in the selection cutting treatment. Also, it concludes that the greater the intensity of felling, the larger the current increment of square mean diameter. On the other hand, the selection cutting treatment has shown the highest percentage of regeneration, followed by the transformation to uneven-aged stand treatment. Finally, facing the difficulties in locating new plots in the study area and after confirming the strong similarity between both thinning intensities, the low thinning regime has been substituted by preparatory fellings treatment before shelterwood regeneration system is applied at a later stage and with a final rotation age of 80 years. The results of this research, with all precaution until they can be confirmed in 10-20 years, allow a set of fir, [CA] L’any 2009 es va establir una xarxa de 15 parcel·les permanents en una massa coetània de Pinus halepensis Mill. en el MUP V154 “La Hunde i La Palomera” (Ayora, València) amb l’objectiu d’avaluar diferents tècniques de gestió selvícola en aquesta espècie. Es tracta d’un fustal de 60 anys procedent de repoblació en el que es van aplicar tractaments d’aclarida baixa dèbil, aclarida baixa forta, huroneig diamètric i transformació a irregular. Cada tractament constava de tres repeticions y, a més a més, es van establir 3 parcel·les control. El present treball té l’objectiu d’analitzar l’efecte que aquests primers tractaments i dos pertorbacions posteriors per vent i neu (2010 i 2017) han tingut sobre el desenvolupament de la massa estudiada. En cada tractament s’han analitzat les principals variables dasomètriques, el nivell de regeneració i la coberta de matoll. S’han tornat a aplicar les tallades seguint la mateixa metodologia per tal de consolidar conclusions en els pròxims 10-20 anys. Després d’analitzar els danys causats pels temporals, es conclou que les primeres intervencions han millorat l’estabilitat del total de la massa, si bé les intervencions més intenses impliquen majors riscos de caiguda d’arbres en els anys immediatament posteriors. En referència a les característiques dasomètriques, les diferencies entre els tractaments de clara baixa dèbil y forta s’han mostrat marginals, y s’ha observat que, a major intensitat de les intervencions, major creixement corrent en diàmetre mitjà. A més a més, s’han detectat indicis d’un sacrifici de producció en el tractament d’huroneig que no es produeixen en el tractament d’irregular. D’altra banda, pel que fa a la regeneració, el tractament d’huroneig es el que ha presentat els millors resultats, seguit de la transformació a irregular. En aquest últim cas, destaca l’elevada presencia de Ulex parviflorus Pourr. Finalment, davant la impossibilitat d’establir noves parcel·les sobre el terreny i després d’haver constata

[ES] En el 2009 se estableció una red de 15 parcelas permanentes en una masa coetánea de Pinus halepensis Mill. en el MUP V154 “La Hunde y La Palomera” de Ayora (Valencia) con el fin de evaluar diferentes técnicas de gestión silvícola en esta especie. Se trata de un fustal de 60 años procedente de repoblación en el que se llevaron a cabo tratamientos de clara por lo bajo débil, clara baja fuerte, huroneo diamétrico y transformación a irregular. Cada tratamiento constó de tres repeticiones y, además, se fijaron tres parcelas testigo. El presente trabajo tiene el objetivo de analizar el efecto que estos primeros tratamientos y dos perturbaciones posteriores por viento y nieve (en 2010 y 2017) han tenido sobre el desarrollo de la masa estudiada. Para cada tratamiento, se han analizado las principales variables dasométricas y el nivel de regeneración y de cobertura de matorral. Se han vuelto a aplicar las cortas siguiendo la misma metodología, a fin de consolidar conclusiones en los próximos 10-20 años. Tras el análisis de los daños por los temporales, se ha concluido que las primeras intervenciones han mejorado la estabilidad del total de la masa, si bien las intervenciones más intensas comportan mayores riesgos de derribos en los años inmediatamente posteriores. Respecto a las características dasométricas, las diferencias entre los tratamientos de clara baja débil y fuerte se han demostrado marginales, y se ha observado que, a mayor intensidad de corta, mayor crecimiento corriente en diámetro medio. Además, se han detectado indicios de un sacrificio de producción en el tratamiento de huroneo, que no se produce en el tratamiento de irregular. Por otra parte, el tratamiento de huroneo es el que ha presentado mejores resultados en cuanto a regeneración, seguido del de transformación a irregular, que también cuenta con una importante presencia de Ulex parviflorus Pourr. Finalmente, ante la imposibilidad de replantear nuevas parcelas sobre el terreno y tras constatar la gr, [EN] In order to evaluate different silvicultural alternatives for even-aged stands of Pinus halepensis Mill. a network of 15 permanent plots was stablished in MUP V154 “La Hunde y La Palomera” (Ayora, Valencia). The stand was planted 60 years ago. Additionally to witness plots, two different thinning intensities, as well as two selection felling treatments with the aim to convert this stands to unevenaged structures, were carried out. The aim of this study is to analyse the effect of these treatments and the damage caused by two storms (in 2010 and 2017) in terms of main stand characteristics, natural regeneration and shrub coverage. By following the same methodology, the different treatments have been carried out for the second time, in order to consolidate conclusions in the next 10-20 years. After analysing the wind and snow damages, results show a noticeable improvement in crop stability 10 years after the fellings, even though the greater intensities imply a higher risk of windthrows the years immediately after the interventions. In regard to stand characteristics, the differences between both thinning methods have turned out to be minimal, and an evidence of a loss of yield by volume has been detected in the selection cutting treatment. Also, it concludes that the greater the intensity of felling, the larger the current increment of square mean diameter. On the other hand, the selection cutting treatment has shown the highest percentage of regeneration, followed by the transformation to uneven-aged stand treatment. Finally, facing the difficulties in locating new plots in the study area and after confirming the strong similarity between both thinning intensities, the low thinning regime has been substituted by preparatory fellings treatment before shelterwood regeneration system is applied at a later stage and with a final rotation age of 80 years. The results of this research, with all precaution until they can be confirmed in 10-20 years, allow a set of fir, [CA] L’any 2009 es va establir una xarxa de 15 parcel·les permanents en una massa coetània de Pinus halepensis Mill. en el MUP V154 “La Hunde i La Palomera” (Ayora, València) amb l’objectiu d’avaluar diferents tècniques de gestió selvícola en aquesta espècie. Es tracta d’un fustal de 60 anys procedent de repoblació en el que es van aplicar tractaments d’aclarida baixa dèbil, aclarida baixa forta, huroneig diamètric i transformació a irregular. Cada tractament constava de tres repeticions y, a més a més, es van establir 3 parcel·les control. El present treball té l’objectiu d’analitzar l’efecte que aquests primers tractaments i dos pertorbacions posteriors per vent i neu (2010 i 2017) han tingut sobre el desenvolupament de la massa estudiada. En cada tractament s’han analitzat les principals variables dasomètriques, el nivell de regeneració i la coberta de matoll. S’han tornat a aplicar les tallades seguint la mateixa metodologia per tal de consolidar conclusions en els pròxims 10-20 anys. Després d’analitzar els danys causats pels temporals, es conclou que les primeres intervencions han millorat l’estabilitat del total de la massa, si bé les intervencions més intenses impliquen majors riscos de caiguda d’arbres en els anys immediatament posteriors. En referència a les característiques dasomètriques, les diferencies entre els tractaments de clara baixa dèbil y forta s’han mostrat marginals, y s’ha observat que, a major intensitat de les intervencions, major creixement corrent en diàmetre mitjà. A més a més, s’han detectat indicis d’un sacrifici de producció en el tractament d’huroneig que no es produeixen en el tractament d’irregular. D’altra banda, pel que fa a la regeneració, el tractament d’huroneig es el que ha presentat els millors resultats, seguit de la transformació a irregular. En aquest últim cas, destaca l’elevada presencia de Ulex parviflorus Pourr. Finalment, davant la impossibilitat d’establir noves parcel·les sobre el terreny i després d’haver constata

[ES] En el 2009 se estableció una red de 15 parcelas permanentes en una masa coetánea de Pinus halepensis Mill. en el MUP V154 “La Hunde y La Palomera” de Ayora (Valencia) con el fin de evaluar diferentes técnicas de gestión silvícola en esta especie. Se trata de un fustal de 60 años procedente de repoblación en el que se llevaron a cabo tratamientos de clara por lo bajo débil, clara baja fuerte, huroneo diamétrico y transformación a irregular. Cada tratamiento constó de tres repeticiones y, además, se fijaron tres parcelas testigo. El presente trabajo tiene el objetivo de analizar el efecto que estos primeros tratamientos y dos perturbaciones posteriores por viento y nieve (en 2010 y 2017) han tenido sobre el desarrollo de la masa estudiada. Para cada tratamiento, se han analizado las principales variables dasométricas y el nivel de regeneración y de cobertura de matorral. Se han vuelto a aplicar las cortas siguiendo la misma metodología, a fin de consolidar conclusiones en los próximos 10-20 años. Tras el análisis de los daños por los temporales, se ha concluido que las primeras intervenciones han mejorado la estabilidad del total de la masa, si bien las intervenciones más intensas comportan mayores riesgos de derribos en los años inmediatamente posteriores. Respecto a las características dasométricas, las diferencias entre los tratamientos de clara baja débil y fuerte se han demostrado marginales, y se ha observado que, a mayor intensidad de corta, mayor crecimiento corriente en diámetro medio. Además, se han detectado indicios de un sacrificio de producción en el tratamiento de huroneo, que no se produce en el tratamiento de irregular. Por otra parte, el tratamiento de huroneo es el que ha presentado mejores resultados en cuanto a regeneración, seguido del de transformación a irregular, que también cuenta con una importante presencia de Ulex parviflorus Pourr. Finalmente, ante la imposibilidad de replantear nuevas parcelas sobre el terreno y tras constatar la gr, [EN] In order to evaluate different silvicultural alternatives for even-aged stands of Pinus halepensis Mill. a network of 15 permanent plots was stablished in MUP V154 “La Hunde y La Palomera” (Ayora, Valencia). The stand was planted 60 years ago. Additionally to witness plots, two different thinning intensities, as well as two selection felling treatments with the aim to convert this stands to unevenaged structures, were carried out. The aim of this study is to analyse the effect of these treatments and the damage caused by two storms (in 2010 and 2017) in terms of main stand characteristics, natural regeneration and shrub coverage. By following the same methodology, the different treatments have been carried out for the second time, in order to consolidate conclusions in the next 10-20 years. After analysing the wind and snow damages, results show a noticeable improvement in crop stability 10 years after the fellings, even though the greater intensities imply a higher risk of windthrows the years immediately after the interventions. In regard to stand characteristics, the differences between both thinning methods have turned out to be minimal, and an evidence of a loss of yield by volume has been detected in the selection cutting treatment. Also, it concludes that the greater the intensity of felling, the larger the current increment of square mean diameter. On the other hand, the selection cutting treatment has shown the highest percentage of regeneration, followed by the transformation to uneven-aged stand treatment. Finally, facing the difficulties in locating new plots in the study area and after confirming the strong similarity between both thinning intensities, the low thinning regime has been substituted by preparatory fellings treatment before shelterwood regeneration system is applied at a later stage and with a final rotation age of 80 years. The results of this research, with all precaution until they can be confirmed in 10-20 years, allow a set of fir, [CA] L’any 2009 es va establir una xarxa de 15 parcel·les permanents en una massa coetània de Pinus halepensis Mill. en el MUP V154 “La Hunde i La Palomera” (Ayora, València) amb l’objectiu d’avaluar diferents tècniques de gestió selvícola en aquesta espècie. Es tracta d’un fustal de 60 anys procedent de repoblació en el que es van aplicar tractaments d’aclarida baixa dèbil, aclarida baixa forta, huroneig diamètric i transformació a irregular. Cada tractament constava de tres repeticions y, a més a més, es van establir 3 parcel·les control. El present treball té l’objectiu d’analitzar l’efecte que aquests primers tractaments i dos pertorbacions posteriors per vent i neu (2010 i 2017) han tingut sobre el desenvolupament de la massa estudiada. En cada tractament s’han analitzat les principals variables dasomètriques, el nivell de regeneració i la coberta de matoll. S’han tornat a aplicar les tallades seguint la mateixa metodologia per tal de consolidar conclusions en els pròxims 10-20 anys. Després d’analitzar els danys causats pels temporals, es conclou que les primeres intervencions han millorat l’estabilitat del total de la massa, si bé les intervencions més intenses impliquen majors riscos de caiguda d’arbres en els anys immediatament posteriors. En referència a les característiques dasomètriques, les diferencies entre els tractaments de clara baixa dèbil y forta s’han mostrat marginals, y s’ha observat que, a major intensitat de les intervencions, major creixement corrent en diàmetre mitjà. A més a més, s’han detectat indicis d’un sacrifici de producció en el tractament d’huroneig que no es produeixen en el tractament d’irregular. D’altra banda, pel que fa a la regeneració, el tractament d’huroneig es el que ha presentat els millors resultats, seguit de la transformació a irregular. En aquest últim cas, destaca l’elevada presencia de Ulex parviflorus Pourr. Finalment, davant la impossibilitat d’establir noves parcel·les sobre el terreny i després d’haver constata

Aim of study: The main aims of this study were to determine of damage level to residual stand and soil disturbance from mechanized selection logging. Area of study: Mixed beech stands in Caspian forests, northern Iran.Material and methods: Point-transect and systematic plot sampling were used for assessing damages to soil and trees, respectively.Main results: 89% of forest soil area was undisturbed or shallow disturbed, and 5.2% was deep disturbed. Soil bulk density of top 10 cm in the winching corridors, ruts and skid trails were increased 10.7%, 20.6% and 32.1% respectively than controlled area. Frequency of damages to regeneration and trees were 12% and 11.2%. The frequency of damages to regeneration was increased with increasing of their heights, but frequency of damages to trees was decreased with increasing of their diameter. The most type of damages was bole wounds in sizes of 100 to 200 cm2 within 1 m from the ground level, and deep wounds. The frequency of damages was different in tree species (p = 0.001). The mean size of bole wounds was 174 cm2, and the mean height of bole wounds was 70 cm from ground level. The intensity of wounds on trees bole were decreased with increasing of their heights from ground level (p = 0.02), while their sizes were increased (p = 0.001).Research highlights: Winching of logs was the main cause of damages to soil and residual stand. The detailed planning strategy will reduce damage to level which is acceptable and predictable.

Aim of study: The main aims of this study were to determine of damage level to residual stand and soil disturbance from mechanized selection logging. Area of study: Mixed beech stands in Caspian forests, northern Iran.Material and methods: Point-transect and systematic plot sampling were used for assessing damages to soil and trees, respectively.Main results: 89% of forest soil area was undisturbed or shallow disturbed, and 5.2% was deep disturbed. Soil bulk density of top 10 cm in the winching corridors, ruts and skid trails were increased 10.7%, 20.6% and 32.1% respectively than controlled area. Frequency of damages to regeneration and trees were 12% and 11.2%. The frequency of damages to regeneration was increased with increasing of their heights, but frequency of damages to trees was decreased with increasing of their diameter. The most type of damages was bole wounds in sizes of 100 to 200 cm2 within 1 m from the ground level, and deep wounds. The frequency of damages was different in tree species (p = 0.001). The mean size of bole wounds was 174 cm2, and the mean height of bole wounds was 70 cm from ground level. The intensity of wounds on trees bole were decreased with increasing of their heights from ground level (p = 0.02), while their sizes were increased (p = 0.001).Research highlights: Winching of logs was the main cause of damages to soil and residual stand. The detailed planning strategy will reduce damage to level which is acceptable and predictable.

Selection cutting is a treatment that emulates tree-by-tree replacement for forests with uneven-age structures. It creates small openings in large areas and often generates a more homogenous forest structure (fewer large leaving trees and defective trees) that differs from old-growth forest. In this study, we evaluated whether this type of harvesting has an impact on genetic diversity of sugar maple (Acer saccharum Marshall). Genetic diversity among seedlings, saplings, and mature trees was compared between selection cut and old-growth forest stands in Québec, Canada. We found higher observed heterozygosity and a lower inbreeding coefficient in mature trees than in younger regeneration cohorts of both forest types. We detected a recent bottleneck in all stands undergoing selection cutting. Other genetic indices of diversity (allelic richness, observed and expected heterozygosity, and rare alleles) were similar between forest types. We concluded that the effect of selection cutting on the genetic diversity of sugar maple was recent and no evidence of genetic erosion was detectable in Québec stands after one harvest. However, the cumulative effect of recurring applications of selection cutting in bottlenecked stands could lead to fixation of deleterious alleles, and this highlights the need for adopting better forest management practices.

Selection cutting, where approximately 30% of the trees are removed every 30 years, is the main silvicultural treatment used in temperate deciduous forests of Quebec (Canada). Concerns have been raised that the use of heavy machinery is creating soil disturbances that are negatively affecting the growth and survival of remaining trees. The aim of the study was to determine if heavy machinery is affecting the growth, morphology, and architecture of sugar maple (Acer saccharum Marsh.) fine roots in and around machinery tracks left after selection logging. The study site, a sugar maple dominated stand, was located in southern Quebec. Root ingrowth bags and standard root cores were used to compare fine root growth, morphology, and architecture in and around machinery tracks one year after logging. Fine root growth of maple was reduced fivefold in both primary (multiple trip) and secondary (only one trip) machinery tracks compared with the control. There was a nonstatistical reduction in fine root growth within 1 m of the tracks. Because machinery tracks cover between 15% and 25% of a stand after selection logging, such reduction in fine root growth could be significant for the growth and survival of the remaining mature maple trees.

Selection cutting, where approximately 30% of the trees are removed every 30 years, is the main silvicultural treatment used in temperate deciduous forests of Quebec (Canada). Concerns have been raised that the use of heavy machinery is creating soil disturbances that are negatively affecting the growth and survival of remaining trees. The aim of the study was to determine if heavy machinery is affecting the growth, morphology, and architecture of sugar maple (Acer saccharum Marsh.) fine roots in and around machinery tracks left after selection logging. The study site, a sugar maple dominated stand, was located in southern Quebec. Root ingrowth bags and standard root cores were used to compare fine root growth, morphology, and architecture in and around machinery tracks one year after logging. Fine root growth of maple was reduced fivefold in both primary (multiple trip) and secondary (only one trip) machinery tracks compared with the control. There was a nonstatistical reduction in fine root growth within 1 m of the tracks. Because machinery tracks cover between 15% and 25% of a stand after selection logging, such reduction in fine root growth could be significant for the growth and survival of the remaining mature maple trees.