Tree Damage Research Articles

Treatment of Lime Witches’ Broom Phytoplasma-Infected Mexican Lime with a Resistance Inducer and Study of its Effect on Systemic Resistance

Destruction caused by plant diseases is terrible. Mexican lime witches' broom (MLWB) is a phytoplasma disease, which has caused considerable damage in Mexican lime tree in southern parts of Iran. In order to protect the plant against this pathogen, it is required to apply an appropriate treatment to induce resistance. Moreover, for better comprehension of disease mechanism, the analysis of phytohormones as one of the most critical basic components in plant cells, probably involved in resistance mechanisms, is of great importance. In this work, Mexican lime trees infected with lime witches’-broom phytoplasma (LWBP) were treated with Previcur EnergyTm (31% fosetyl-Alluminum plus 53% propamocarb) 4/000 as the resistance inducer against phytoplasma. In the next step, phytohormone levels in healthy Mexican lime were compared with those of infected and treated lime trees. For analysis of phytohormones, one-step dispersive solid phase extraction (DSPE) combined with liquid chromatography-tandem mass spectrometry-multiple reaction monitoring (LC–MS/MS-MRM) mode was used. A total of 54 phytohormones including cytokinins, auxins, jasmonates, gibberellins, salicylic acid and abscisic acid groups were simultaneously analyzed for treated, infected, and healthy plants. Totally, 18 phytohormones from plant leave extract were detected, among which levels of 11 phytohormones including SA, JA, JA-Phe, JA-Ile, JA-Leu, OPDA, CZ, iP7G, cZ9G, TZr and 2MeStZR were significantly changed in both infected and treated plants. Result of the present study indicated that the applied treatment was able to reduce the severity score in plant. On the other hand, phytoplasma (as a biotic stress) and treatment with Previcur EnergyTm (as a resistance inducer) could affect fundamental processes in plant via regulation of phytohormone levels.

Complications of Cryptosporidium infection after pediatric liver transplantation: Diarrhea, rejection, and biliary disease.

Cryptosporidium enteritis can be devastating in the immunocompromised host. In pediatric liver transplant recipients, infection may be complicated by prolonged carriage of the parasite, rejection, and biliary tree damage and fibrosis. Herein, we report on six patients and their long-term outcomes following cryptosporidiosis. We reviewed all cases of cryptosporidiosis in a pediatric liver transplant population over a 17-year period at a single center. Six patients with infection were identified, and their outcomes were analyzed. Infection was associated with significant diarrhea and dehydration in all cases, and led to hospitalization in one-half of patients. Four of the six patients developed biopsy-proven rejection following infection, with three of those patients developing rejection that was recalcitrant to intravenous steroid treatment. Additionally, three patients developed biliary tree abnormalities with similarity to sclerosing cholangitis. In one patient, those biliary changes led to repeated need for biliary drain placement and advancing fibrotic liver allograft changes. Cryptosporidiosis in pediatric liver transplant recipients may lead to significant complications, including recalcitrant episodes of rejection and detrimental biliary tree changes. We advocate for increased awareness of this cause of diarrheal disease and the allograft injuries that may accompany infection.

Level of damage on sengon stand based on tree vitality indicators at sengon community forest in Serang District, Banten Province

Sengon plantation is the primary commodity of the community forests, which produces timber with high economic value, especially in Java Island. However, now the condition of sengon stands in Java Island, pests and diseases have attacked most. The information about the health and the severity of the stands due to pests and diseases is beneficial for determining stand productivity and investment security. The purpose of this activity is to determine the level of damage on sengon stands at various locations in Serang Regency, Banten, based on indicators of tree vitality. The method used to determine stand health is Forest Health Monitoring (FHM), which includes using tree vitality indicators and site quality indicators as a basis for assessment. The observation plot was carried out at 3 locations determined purposively based on the flat distance from the beach, which is ≤ 2 km; 2> X≤ 4 km; 4> X ≤6 km. The results showed that the average percentage of healthy sengon trees was still quite high (82.7%), but the level of damage to stands was moderate. The most common type of damage is gummosis (distance ≤ 2 km and > 4-6 km) and boktor (> 2-4 km). Many tree damage occurs in the main branch location found in the live canopy section (code 6), especially in plots that are 2> X≤ 4 km from the coastline and lower stem (distance ≤ 2 km). However, no damage was found at the root location (code 1), shoots (code 8) and leaves (code 9). The damage of the stem causes a decrease in wood production because the damaged at part of the stem cannot be used anymore. Visual Crown Ratio of sengon trees tends to be low due to young trees so that the canopy is not maximal. Maintenance activities, as well as mixed planting techniques with intercropping plants and other woody plants, can prevent sengon plants from attacking pests and diseases.

Effect of Day or Night and Cumulative Shift Time on the Frequency of Tree Damage during CTL Harvesting in Various Stand Conditions

Thinning is one of the most important tools of forest management, although thinning operations require the use of machines which ultimately cause damage to the remaining stand. The level of damage largely depends on the human factor, and a tired, less focused operator will create more injuries in the forest. With this in mind, the objectives of this research were to find out whether the probability of tree damage caused by an operator is also affected by: (1) the part of the day (dawn/day/dusk/night), and (2) the cumulative shift time. The research was carried out in pure pine stands of different ages, density and thinning intensities. Sample plots were selected that had an increasing number of trees per hectare and growing thinning intensities were applied. The same Komatsu 931.1 harvester was used for the thinning operations in each stand. In all the age classes combined, 5.41% of the remaining trees were wounded. There was a significant influence of the part of the day on the percentage of damaged trees, which was positively correlated with the cumulative shift time. Stand conditions, such as age class and stand density, as well as thinning characteristics—thinning intensity, number of harvested trees and productivity—have different effects on the distribution of damage intensity and on probability. The results may improve the planning of operators’ work shifts in forests of various ages and densities, allowing harvester productivity to be maintained while at the same time inflicting the lowest possible level of damage.

Pantropical geography of lightning-caused disturbance and its implications for tropical forests.

Lightning is a major agent of disturbance, but its ecological effects in the tropics are unquantified. Here we used ground and satellite sensors to quantify the geography of lightning strikes in terrestrial tropical ecosystems, and to evaluate whether spatial variation in lightning frequency is associated with variation in tropical forest structure and dynamics. Between 2013 and 2018, tropical terrestrial ecosystems received an average of 100.4 million lightning strikes per year, and the frequency of strikes was spatially autocorrelated at local-to-continental scales. Lightning strikes were more frequent in forests, savannas, and urban areas than in grasslands, shrublands, and croplands. Higher lightning frequency was positively associated with woody biomass turnover and negatively associated with aboveground biomass and the density of large trees (trees/ha) in forests across Africa, Asia, and the Americas. Extrapolating from the only tropical forest study that comprehensively assessed tree damage and mortality from lightning strikes, we estimate that lightning directly damages c. 832 million trees in tropical forests annually, of which c. 194 million die. The similarly high lightning frequency in tropical savannas suggests that lightning also influences savanna tree mortality rates and ecosystem processes. These patterns indicate that lightning-caused disturbance plays a major and largely unappreciated role in pantropical ecosystem dynamics and global carbon cycling.

Lightning Damage Facilitates Beetle Colonization of Tropical Trees

Abstract Lightning is a common agent of disturbance in many forest ecosystems. Lightning-damaged trees are a potentially important resource for beetles, but most evidence for this association is limited to temperate pine forests. Here, we evaluated the relationship between lightning damage and beetle colonization of tropical trees. We recorded the number of beetle holes on the trunks of trees from 10 strike sites (n = 173 lightning-damaged trees) and 10 matching control sites (n = 137 control trees) in Panama. The trunks of lightning-struck trees had 370% more beetle holes than control trees. The abundance of beetle holes increased with increasing total crown dieback among both control and lightning-damaged trees, and with larger tree diameter among lightning-struck trees. Beetle holes also were more abundant in trunk sections of lightning-damaged trees located directly below a damaged section of the crown. The results of this study suggest that lightning damage facilitates beetle colonization in tropical forest trees and provide a basis for investigations of the effects of lightning-caused disturbance on beetle population dynamics and assemblage structure.

Short-Term Recovery of Residual Tree Damage during Successive Thinning Operations

In this study, damage to residual trees during thinning performed by motor-manual felling and whole tree skidding was studied in a loblolly pine (Pinus taeda L.) plantation. Forest intervention was carried out in 2016 and tree wounds were studied and examined over a period of three years. The results indicated that 8% of the residual trees suffered damage, of which 52% was caused by felling operations and 48% by extraction operations. Among the damaged trees, 13% had damage to the root system, 53% to the bole, and 34% to the crown area. The average wound size at the time of occurrence was 71.3 cm2. This was found to be reduced to 54.4 cm2 after a three year period. Wound intensity decreased with higher wound height and increased size. Three years after wound occurrence, only 6.6% were closed, 90.6% were still open, and 2.8% were decayed. The diameter growth in damaged trees was 1.7% lower than in undamaged trees (p > 0.05). Damage to the root system of residual trees reduced diameter growth by 3% (p < 0.05). Intensive wounds (damaged wood) caused a reduction of 22.7% in diameter growth (p < 0.01). In addition, the diameter growth in trees with decayed wounds was 27.4% lower than unwounded trees (p < 0.01). Pre-harvest planning, directional tree felling, marking of the extraction path before logging operations, employment of skilled logging workers, and post-harvest assessment of damaged residual trees are essential implementations in timber plantations.

Oil Spill in Pulau Rambut and its possible long-term impact on mangrove as waterbirds habitat

In July 2019, an oil spill incident in the northern West Java has reached Pulau Rambut, a Wildlife Sanctuary dedicated for waterbird in Jakarta Bay, Indonesia. The objective of this paper was to record the number of mangrove trees exposed to the oil spill, and provide desk-study analysis of the possible long-term impact of the mangrove. Field visit were conducted on 19 and 22 August. Trees along waterways were examined, plots were stablished in the exposed and non-exposed area. The rhizophores of all trees (n=26) along waterways were covered by the sticky-melted crude-oil, while some leaves were also covered. In the exposed areas, 47 trees (63.51%) were covered by oil, either heavily or partially. For the younger trees, 43.08% poles, 78.74% saplings and 67.35% seedlings were oiled. Desk-study suggested that death of mangrove was not instant, up to one year after the incident for seedlings/sapling. Structural damage of mature trees happened in year-3. Trees and their ecosystem will stabilize in year-5, and recovery can be expected in year-9. As the trees are extremely important for waterbirds, a continuous monitoring of mangrove health need to be conducted to ensure that the waterbirds will not lose their nesting habitat in the future.

Application of art-therapeutic methods in the rehabilitation of cardiac patients

The article describes the application of art therapeutic methods of rehabilitation of cardiological patients, specifics of the use of art therapy in rehabilitation processes, the symbolic meaning of the tree, art therapeutic methods using the image of the damaged tree, its algorithms, the schemes of stricture interrogation, interpretation of drawings of the damaged tree, an example of the method use.

Tree Damage by Ice Accumulation in Norway Spruce (Picea abies (L.) Karst.) Stands Regarding Stand Characteristics

Freezing rain is a frequently occurring, but relatively rarely studied disturbance in Europe, although ice accumulation may occasionally cause severe damage for forestry. We aimed to characterize ice-accumulation damage to overstory trees in spruce stands, assess the probability of damage based on the stand and individual tree parameters, and define the most significant parameters that affect the probability of individual tree damage in all stands and in recently thinned stands. Among the studied stands, the proportion of damaged overstory spruce ranged from 1.8% to 60.9% and was higher (p < 0.001) in recently thinned stands (27.8% ± 1.9%) than in the other stands (20.4% ± 1.6%). Stem breakage was the prevalent (98.5% ± 1.1%) damage type. At the stand level, the probability of damage decreased for older, less dense stands with a larger mean diameter. Within stands, overstory trees were more damaged (23.5% ± 1.2%; p < 0.001) than those in the lower stand layers, but, within overstory, trees with larger dimensions and a higher social position (high relative diameter and low slenderness ratio) and a higher proportion of crown were less damaged. The probability of breakage to overstory trees was most accurately predicted using almost the same variables for all stands and recently thinned stands. The site type, tree height, relative diameter, and crown ratio were common for both, with the addition of mean diameter at breast height for all stands and the stand density for recently thinned stands. Our results indicate the importance of the tree and stand characteristics on the resistance of individual tree to ice accumulation and the need for management practices that balance increased growth and the stability of trees throughout the rotation.

Performance evaluation of lateral canopy shakers with catch frame for continuous harvesting of oranges for juice industry

Citrus is mainly oriented to fresh consumption, and harvesting is usually performed manually. However, the high cost of harvesting and the low availability of labour can compromise the profitability of the crop when it is destined to juice industry. The development of citrus mechanical harvesting for industrial processing is conditioned to reach a high fruit removal efficiency, with a reduced damage to both fruit and trees. The current machines available are very large, requiring extensive plantations with long rows of trees to be efficient. In this study, two lateral canopy shakers equipped with a catch frame were evaluated to harvest independently both sides of the hedge on intensive citrus plantations with the main objective of determining their performance and feasibility. The lateral canopy shakers tested were three tractor-drawn machines, one commercial machine and two prototypes. The tested machines reached a mean value of 78% of fruit removal. Besides, the prototypes, equipped with a catch frame, were able to recover a mean value of 70% of yield. Although the results were promising, for achieving an efficient result, the application of this harvesting technology still requires a process of improvement, and the adaptation of both the machine and the plantation. The machines should reduce the amount of post-harvest ground fruit (5.9%-10.4%). Tree damages generated by the contact of the catch frame with the trunk and the metal rods with main branches were the most relevant. Therefore, it is still necessary to increase the ground speed of the machinery and improving the design of the rods, regulating the rod penetrating deep in the canopy to improve the fruit recovery and limit the damage caused to the trees. Keywords: harvester, mechanical harvesting, fruit removal, tree damage, Citrus sinensis L. Osbeck DOI: 10.25165/j.ijabe.20201303.4998 Citation: Sola-Guirado R R, Castro-Garcia S, Blanco-Roldan G L, Gil-Ribes J A, Gonzalez-Sanchez E J. Performance evaluation of lateral canopy shakers with catch frame for continuous harvesting of oranges for juice industry. Int J Agric & Biol Eng, 2020; 13(3): 88–93.

Persistent changes in the horizontal and vertical canopy structure of fire-tolerant forests after severe fire as quantified using multi-temporal airborne lidar data

Wildfires can influence the canopy structure of resprouter forests in multiple ways including crown scorching and consumption, tree damage and mortality, and changes in resources available for recovery. Few studies have quantified post-fire changes in the canopy structure of fire-tolerant eucalypt forests, which limits understanding of the extent and persistence of fire effects on ecosystem processes including interactions with environment. In this study, we assess the impacts of a landscape-scale wildfire on the canopy structure of fire-tolerant eucalypt forests in temperate Australia using metrics derived from airborne lidar data. Our assessment, made seven years after the wildfire, encompassed four fire severities (unburnt, low, moderate, high) and involved 1084 lidar plots (0.06 ha, including validation using 51 field plots) across an area of ~30,000 ha in a single forest type. We used Random Forest models to examine the relative importance of fire severity, pre-fire canopy metrics, climate and topography to the prediction of seven post-fire metrics representing the horizontal and vertical structure of the full canopy, the dominant and sub-dominant strata. Canopy cover at seven years post-fire was significantly reduced in moderate- and particularly high-severity plots (mean decrease of 30%). High-severity fire also decreased mean canopy height and led to changes in the canopy relief ratio and rumple index consistent with a dominant stratum that was more heterogeneous and fragmented. In addition to fire severity, the pre-fire values of each metric were important to their post-fire prediction, suggesting that canopy structural recovery after this fire could have been influenced by any lingering effects of previous fires. Topographic and climatic variables were of comparatively minor importance to the prediction of post-fire canopy metrics, although relationships with the forest drought stress index indicated that canopy recovery was slowest at the driest sites. Our study provides quantitative evidence of significant changes in the canopy structure of fire-tolerant eucalypt forests that persisted for at least seven years after high-severity wildfire. Recent trends in southern Australia of shortened wildfire intervals and a drier climate will likely narrow the windows for canopy recovery of fire-tolerant forests, realizing predictions of a gradual opening and fragmentation of forest canopies in temperate Australia and associated changes in multiple ecosystem processes.

Dating of rockfall damage in trees yields insights into meteorological triggers of process activity in the French Alps

Rockfall release is a rather unpredictable process. As a result, the occurrence of rockfall often threatens humans and (infra)structures. The assessment of potential drivers of rockfall activity therefore remains a major challenge, even if the relative influence of rainfall, snowmelt, or freeze–thaw cycles has long been identified in short‐term monitoring projects. In the absence of longer‐term assessments of rockfall triggers and possible changes thereof, our knowledge of rockfall dynamics remains still lacunary as a result of the persisting scarcity of exhaustive and precise rockfall databases. Over the last decades, several studies have employed growth disturbances (GDs) in tree‐ring series to reconstruct rockfall activity. Paradoxically, these series were only rarely compared to meteorological records. In this study, we capitalize on the homogeneity of a centennial‐old reforestation plot to develop two reconstructions – R1 including only growth suppressions, and R2 based on injuries – with limited biases related to decreasing sample size and changes in exposed diameters back in time. By doing so, our study also and quite clearly highlights the large potential that protection forests have in terms of yielding reliable, multidecadal rockfall reconstructions. From a methodological perspective, we find no synchronicity between R1 and R2, as well as an absence of meteorological controls on rockfall processes in R1. This observation pleads for a careful selection of GDs in future reconstructions. In terms of process dynamics, we demonstrate that summer intense rainfall events (>10 mm day−1) are the main drivers for rockfall activity at our study site. Despite the stringency of our detection procedure, correlations between rockfall activity and meteorological variables remain comparable to those reported in previous studies, as a result of the complexity and multiplicity of triggering factors. We therefore call for a more systematic coupling of tree‐ring analysis with rockfall and microclimatic monitoring in future studies. © 2020 John Wiley & Sons, Ltd.

A mechanistic and empirically supported lightning risk model for forest trees

AbstractTree death due to lightning influences tropical forest carbon cycling and tree community dynamics. However, the distribution of lightning damage among trees in forests remains poorly understood.We developed models to predict direct and secondary lightning damage to trees based on tree size, crown exposure and local forest structure. We parameterized these models using data on the locations of lightning strikes and censuses of tree damage in strike zones, combined with drone‐based maps of tree crowns and censuses of all trees within a 50‐ha forest dynamics plot on Barro Colorado Island, Panama.The likelihood of a direct strike to a tree increased with larger exposed crown area and higher relative canopy position (emergent > canopy >>> subcanopy), whereas the likelihood of secondary lightning damage increased with tree diameter and proximity to neighbouring trees. The predicted frequency of lightning damage in this mature forest was greater for tree species with larger average diameters.These patterns suggest that lightning influences forest structure and the global carbon budget by non‐randomly damaging large trees. Moreover, these models provide a framework for investigating the ecological and evolutionary consequences of lightning disturbance in tropical forests.Synthesis. Our findings indicate that the distribution of lightning damage is stochastic at large spatial grain and relatively deterministic at smaller spatial grain (<15 m). Lightning is more likely to directly strike taller trees with large crowns and secondarily damage large neighbouring trees that are closest to the directly struck tree. The results provide a framework for understanding how lightning can affect forest structure, forest dynamics and carbon cycling. The resulting lightning risk model will facilitate informed investigations into the effects of lightning in tropical forests.

Browsing hinders the regeneration of broadleaved trees in uneven-aged forest management in southern Finland

ABSTRACT Uneven-aged forest management has attained increasing popularity. It may benefit biodiversity, buffer against pests and abiotic damages, decrease runoff from clearcuts and improve recreational values. We studied how gap cuttings and single-tree selection cuttings influence browsing damage in spruce-dominated forests in south-central Finland. Overall, browsing damage was especially frequent in aspen and rowan, but also in birch. The larger the basal area left in harvesting, the lower the browsing pressure on birch and rowan; neither the harvesting method nor the seedling density had an independent effect on browsing damage. Although larger tree retention levels may reduce browsing damage, the regeneration and recruitment of shade-intolerant broadleaved trees may be compromised.

Differential responses of tree species to a severe ice storm and their implications to forest composition in the southeast United States

The unique terrain, geography, and climate patterns of the eastern United States encourage periodic occurrences of catastrophic ice storms capable of large-scale damage or destruction of forests. However, the pervasive and persistent effects of these glaze events on regional forest distribution and composition have rarely been studied. In the southeastern US, ice storm frequency and intensity increase with increasing latitude and along the complex gradients from the coast (low, flat, sediment controlled and temperature moderated near the ocean) to the interior (high, rugged, bedrock controlled, distant from warming ocean). To investigate the potential influence of this disturbance gradient on regional forest composition, we studied the differential responses of trees (canopy position, lifeform group, and species group) to a particularly severe ice storm. Our results indicated that tree mortality and damage (canopy damage, bent bole, snapped bole, and uprooted) varied significantly between overstory and understory trees, and among species and lifeform groups. Overstory trees were more prone to glaze damage than understory trees, and evergreen broadleaf species were the most susceptible to glaze damage, while deciduous species were the least susceptible. Among the pine species studied, slash pine (Pinus elliottii Engelm.) and longleaf pine (P. palustris Mill.) suffered more severe damage and mortality than loblolly pine (P. taeda L.). Further, ice damage was correlated with distribution-based differences in injury susceptibility among pine and deciduous tree species. The most ice storm-tolerant pine species, loblolly pine, had the most northerly distribution (39.51°N), while the least resistant species were those with more southerly distribution (e.g., 33.29°N for slash pine). These results support hypotheses that the distributions of evergreen tree species are regulated by periodic catastrophic ice storms. Therefore, predicting future distributions of tree species in response to climate change should consider the role of ice storms in shaping the forest composition.

Logging damage to residual trees during sustainable harvesting of uneven-age stands in the Hyrcanian forests of Iran

Background: The frequency of wounded trees and intensity of wounds during logging operations can have serious impacts on stand growth and forest sustainability. The aims of the study were to evaluate and compare stand (tree and regeneration) damage level, wound characteristics, and damage types occurring when using a cable skidder in salvage logging and selection cutting.
 Methods: This study was conducted on four sites of mixed uneven-aged hardwood stands in the Hyrcanian forests of Iran. At two sites, salvage logging was applied (SL1 and SL2), and low-intensity selection cutting (SC1 and SC2) was applied at the other two. A systematic plot sampling design was used on the study area for damage assessment.
 Results: The percentage of regenerating trees damaged was 2.8, 2.1, 4.3, 1.4 %, in SL1, SL2, SC1, and SC2, respectively. The corresponding percentage of damaged trees was 4.3, 3.7, 4.9, 1.7 %. Most of the damage (48–79%) to the stand occurred during the winching stage at all the sites. Most of the wounds were located on the bole (51–78%). The average wound height and wound size at selection cutting sites were significantly higher than at the salvage logging sites. The incidence of high-intensity wounds at the salvage logging sites (55% at SL1 and 57% at SL2) was higher than at the selection cutting sites (24% in SC1 and 30% in SC2). Regenerating beech (Fagus orienalis Lipsky) and alder (Alnus subcordata C.A.Mey) had the highest incidence of damage. The number of damaged trees increased with increasing winching distance.
 Conclusion: Damage levels in stands during salvage logging and low-intensity selection cutting are lower (about a quarter) than the damage level to residual trees (12–23%) and regeneration (5–11%) from conventional selection cutting in uneven-aged mixed hardwood stands in the Hyrcanian forests. Because of the ecological and conservation value of deadwood, if the incidence of wind-fallen trees is low, the wood should be left in forest stands due to the high cost of salvage logging and the damage caused to residual and regenerating trees.

Recovering From Freeze Damage

This text provides comprehensive guidelines for managing and aiding the recovery of citrus trees following exposure to freezing temperatures. It emphasizes the importance of tree dormancy in reducing susceptibility to cold damage, noting that evergreen citrus trees are less cold-tolerant than deciduous trees. The article outlines symptoms of cold damage, such as drooping leaves, bark splitting, and cold cankers, and describes the proper care needed for bearing groves, including adjusted fertilization, irrigation, and pruning practices. Post-freeze care recommendations include a cautious approach to immediate interventions, reducing fertilizer based on the extent of tree damage, and prioritizing weed control and disease management. The article also covers the specific needs of young trees, suggesting removal of protective banks or wraps to prevent further damage and detailing how to reapply protection as needed. Overall, the article provides a detailed and flexible approach to help citrus growers minimize damage and promote recovery in the aftermath of a freeze. First published in June, 1992.

Soil impacts and residual stand damage from thinning operations

ABSTRACT Thinning has a crucial role in retaining the future value of stands; hence, excessive soil disturbance and damage to residual trees can diminish thinning advantages. The research aims were to assess soil disturbance and the level of stand damage from thinning operations. Thinning intensity ranged from 8.3% to 19.1% of the standing volume. Soil disturbance and damage level to residual trees, were determined in five young even-aged hardwood stands, using ground-based extraction systems. Tree felling was done by chainsaw, and full trees were extracted by a skidder. Point-transect method and systematic sampling plots were used to characterize soil disturbance and residual trees damage, respectively. Surface of disturbed soil ranged from 14% to 27% and stand damage ranged from 5% to 18% of the residual trees and they were significantly increased by increasing thinning intensity. Soil resistance to penetration at a depth of 0–10 cm in the shallow disturbed (0.39 MPa), deep disturbed (0.52 MPa), and skid trails (0.79 MPa) were increased by 14%, 27%, and 54%, respectively, compared to the undisturbed soils (0.25 MPa). Winching was the main cause of soil disturbance and damage to residual trees. The highest frequency of damage was observed on trees with a dbh class of 20 cm (24.3%). Most of the stand damage occurred on the bole (55%) of trees, with wound sizes ranging from 50 to 350 cm2, and most of the wounds (53%) showed damage to the cambium and wood fibers, at heights of <1 m above the ground line (76%).

Borowo, Borki i Boruty. Szlachta i lasy na Podlasiu w XVI - XVII w.

Borowo, Borki and Boruty. The nobility and forests in the Podlasie region in the sixteenth–seventeenth centuries For centuries Podlasie had been one of Poland’s most forested regions. Even its name was sometimes interpreted as a land “under forests”. Apart from the Białowieża Forest in the District of Kamenets, incorporated in 1566 into the new Province of Brest-Litowsk, the most forested area was the region around Bielsk. In addition to ducal (royal) forests, there were also private forests belonging to large noble families, residing mainly in the western part of the region. The aim of the present article is to take a closer look at forests belonging to the nobility as well as the fact that their estates neighboured on forested royal estates throughout the sixteenth century. The colonisation of these worn-torn lands, begun in the late fourteenth century, occurred largely in forest areas, which had to be cleared to make way for villages and arable land. As settlement developed, numerous border disputes arose. They were particularly frequent in the first half of the sixteenth century, until the land reform carried out at the time. After conflicts, sometimes long-standing, over borders were resolved, there began divisions of forests within groups of villages with the same name / origins of their owners. The disputes also involved heirs to the same village. In order to put an end to them the institution of inhibitio was called upon from the 1650s onwards. As a result of this sorting out of ownership issues, the nobility, especially in the first two interregnum periods, turned to royal forest domains, causing damage in trees and animals. Poaching was hard to control given the limited number of forest guards. As a comparison of court records from Brańsk from 1561 and 1591 has demonstrated, forest cases were part of the everyday reality for petty nobility in the Podlasie region in the sixteenth century