Eucalyptus Plantations Research Articles

Some strange substrates for macrofungi in the Pampa Biome - Brazil

Macrofungi usually are found growing on vegetal substrate, soil or dung, but sometimes they have the opportunity to explore some very unusual food. Studying mushrooms in São Gabriel municipality, southern Brazil (Pampa Biome) allow us to collect specimens in different substrata rarely or still not reported in the literature. The collections include Amanita muscaria subsp. flavivolvata growing in Eucalyptus plantation, Clitopilus argentinus growing on a wasp nest, Cheimonophyllum candidissimum growing on rock, Marasmius neosessilis on the shrub Asparagus officinalis (Angiosperm) and Panaeolina foenisecii in Capibara dung. The implications of such ecological relationship are discussed. To Clitopilus a review of the species reported to Brazil is presented.

Effects of Eucalypt Monoculture Plantations on Soil Invertebrate Communities: A Meta‐Analysis

ABSTRACTEucalypt monoculture plantations can adversely impact soil properties. However, a thorough assessment of their effects on soil invertebrate communities is lacking, impeding our ability to acquire a deeper understanding about the potential impacts of these intensively managed plantations on soil functioning. To quantify the effects of eucalypt plantations on soil invertebrate communities, and to identify the main moderators driving these effects, we performed a meta‐analysis of studies reporting the effects of eucalypt monoculture plantations in comparison with other land use types involving different potential levels of disturbance to the soil matrix (native forests, other forestry plantations, croplands, grasslands, integrated crop‐livestock‐forestry, and invasive copses). We addressed these effects on the density (26 studies contributing 143 comparisons) and diversity (14 studies contributing 168 comparisons) of soil invertebrates. Density was lower in eucalypt plantations than in other forestry plantations, but higher than in grasslands and integrated crop‐livestock‐forestry. Diversity was lower in eucalypt plantations compared to native forests, yet higher when compared with other forestry plantations. When compared with other forestry plantations, the effects of eucalypt plantations on soil invertebrates depended on the type of other forestry plantation, the mean annual temperature, and the annual precipitation. Accounting for the diverse effects of eucalypt plantations relative to other land uses and climatic factors, along with the integration of data on soil physico‐chemical properties and different management practices, can contribute to a better understanding of how changes in land cover impact soil invertebrates and help managers to make informed decisions about the establishment of eucalypt plantations.

Grassland Afforestation Drives Biotic Homogenisation of Soil Microbial Communities at a Regional Scale.

Grassland afforestation poses a threat to biodiversity beyond land-use conversion. Diversity patterns are shaped by temporal dynamics, particularly, time since afforestation can decline beta diversity and lead to biotic homogenisation. Our study examines the effect of grassland afforestation on soil prokaryotic and fungal beta diversity. We evaluate the contributions of colonisation and extinction processes to beta diversity, as well as the replacement of endemic species by ubiquitous ones. Along a 200 km climatic gradient in Argentina's Pampas region, we analysed grasslands and mature eucalypt plantations at different times since afforestation. Soil samples were collected at each site and analysed using 16S (V3-V4) and ITS2 amplicon sequencing to identify prokaryotic and fungal communities, respectively. The analyses revealed biotic homogenisation at the transition from grassland to newly planted stands, evidenced by a decrease in intratreatment beta diversity. Increasing time since afforestation did not exacerbate this decline. However, our findings indicate that there are different responses between prokaryotes and fungi. The homogenisation of prokaryotes in young stands is due to the low heterogeneity in colonising communities. On the other hand, the decline in fungal beta diversity is likely caused by other mechanisms beyond extinction or replacement. The study highlights the impacts of the afforestation process on the beta diversity of soil microbial communities of grasslands, affecting taxonomic groups in different ways. Although microbial diversity may be partially restored in time in eucalypt plantations, it is important to investigate its underlying mechanisms and the ecological implications for microbial diversity and its spatial distribution.

Identification of direct and indirect drivers of land use and land cover changes from agriculture to Eucalyptus plantation using the DPSIR framework in Sinan and Mecha Districts of Northwestern Ethiopia

Identification of direct and indirect drivers of land use and land cover changes from agriculture to Eucalyptus plantation using the DPSIR framework in Sinan and Mecha Districts of Northwestern Ethiopia

Rational eucalypt logging site management patterns enhance soil phosphorus bioavailability and reshape phoD-harboring bacterial community structure

Continuous planting of eucalypt plantations negatively affects soil nutrient effectiveness, especially soil phosphorus (P) availability. Therefore, exploring the response characteristics of soil P-mineralising microbial communities and the distribution mechanism of soil P fractions under different transformation patterns on eucalypts logging sites holds great practical significance for improving soil nutrient effectiveness in plantations. This experiment investigated the effects and correlations between four different transformation patterns on soil phoD-harboring bacterial communities, alkaline phosphatase (ALP) activity, and P fractions. Management patterns mainly included non-forest area formed upon eucalypt stump germination suppression after two generations of Eucalyptus afforestation (TWE), the third generation of pure plantation planting (THE), mixing of Eucalyptus with Manglietia glauca (EM), and rotation of pure M. glauca plantation (MM), with previous mixed coniferous and broadleaf forest (CK) as the control. The results showed that, TWE and THE significantly reduced soil (0–10 cm and 10–20 cm) organic carbon (SOC), total nitrogen (TN), bioavailable P, and labile Po, and increased the occluded P and ALP activity compared to CK; however, SOC, TN, bioavailable P, and labile Po indices improved in plantations of EM or MM compared to TWE and THE. Meanwhile, the four management patterns on the logging site caused significant differences in phoD gene community structure and diversity. TWE and THE significantly increased the relative abundances (RAs) of Pseudomonadaceae and Comamonadaceae, which correlated negatively with soil bioavailable P and HCl-P and positively with ALP activity, suggesting a positive effect on Po mineralization and insoluble P mobilization. In contrast, Streptomycetaceae and Oxalobacteraceae were significantly enriched in EM or MM, implying that not all microorganisms carrying phoD genes play important roles in synthesizing ALP. The structure equation model showed that TN, resin-Pi, NaHCO3-Pi, and HCl-P had indirect effects on ALP through phoD-harbouring bacterial diversity and community composition. These findings provide a basis for understanding the soil P cycling mechanism after eucalypt plantations logging site transformation.

Biochar with or Without Nitrogen Fertilizer Influences Soil Microbial Carbon Utilization, Bacterial Diversity, and Nitrogen Dynamics in a Eucalyptus Plantation

Biochar with or Without Nitrogen Fertilizer Influences Soil Microbial Carbon Utilization, Bacterial Diversity, and Nitrogen Dynamics in a Eucalyptus Plantation

Climate Change Effects on Land Use and Land Cover Suitability in the Southern Brazilian Semiarid Region

Climate change is expected to alter the environmental suitability of land use and land cover (LULC) classes globally. In this study, we investigated the potential impacts of climate change on the environmental suitability of the most representative LULC classes in the southern Brazilian semiarid region. We employed the Random Forest algorithm trained with climatic, soil, and topographic data to project future LULC suitability under the Representative Concentration Pathway RCP 2.6 (optimistic) and 8.5 (pessimistic) scenarios. The climate data included the mean annual air temperature and precipitation from the WorldClim2 platform for historical (1970–2000) and future (2061–2080) scenarios. Soil data were obtained from the SoilGrids 2.1 digital soil mapping platform, while topographic data were produced by NASA’s Shuttle Radar Topography Mission (SRTM). Our model achieved an overall accuracy of 60%. Under the worst-case scenario (RCP 8.5), croplands may lose approximately 8% of their suitable area, while pastures are expected to expand by up to 30%. Areas suitable for savannas are expected to increase under both RCP scenarios, potentially expanding into lands historically occupied by forests, grasslands, and eucalyptus plantations. These projected changes may lead to biodiversity loss and socioeconomic disruptions in the study area.

Soil legacies left by a 20-year eucalypt plantation and a secondary vegetation covers on young eucalypt plants and plant-soil feedback

Soil legacies left by a 20-year eucalypt plantation and a secondary vegetation covers on young eucalypt plants and plant-soil feedback

Optimizing multiple ecosystem services in Eucalyptus plantations: Dual effects of intercropping and restoration

Mixed plantations of Eucalyptus with native tree species can effectively improve forest ecosystem services. However, the long-term effects and ratios of Eucalyptus-native tree species mixture on plant diversity in different plant layer, multiple ecosystem services, multiservice and the underlying mechanisms remain unclear. To fill these gaps, a four-level intercropping gradient of Eucalyptus urophylla planted with eight native tree species (NS) was set up (i.e., 20%NS, 30%NS, 40%NS, 50%NS), monitored and compared with a monoculture E. urophylla plantation (EU) and a randomly mixed plantation (98%NS) in southern China. We calculated the multiple ecosystem services of the plantation and the multidimensional diversity (taxonomic diversity (TD), functional diversity (FD), and phylogenetic diversity (PD)) of different plant layers. The results showed that the long-term (13–15a) and short-term (1a) plantation communities were significantly different in multidimensional diversity in all three vertical plant layers. In the long-term, intercropping with more than 20% native trees significantly increased the multidimensional diversity in the tree layer, but not the shrub and herb layers, compared to the EU. Intercropping with 50% native trees significantly promoted biodiversity conservation service, ecosystem multiservice and synergistic relationships among ecosystem services over a decade. Both initial mixing ratio and naturally restored multidimensional diversity in shrub and herb layers influenced tree layer's multidimensional diversity, contributing to long-term multiple ecosystem services of mixed Eucalyptus-native tree species plantations. Our results highlighted the risk of applying short-term based diversity results in long-term strategy making for E. urophylla plantation, quantitatively explored the high explanatory power of plant functional and phylogenetic diversities on multiservice, and expanded understanding of the mechanisms of the triad, biodiversity-ecosystem service-ecosystem stability. To practice, intercropping 50% native trees was recommend for long-term optimizing multiservice restoration, including but not limited to biodiversity conservation, and the syngeneic development among ecosystem services of Eucalyptus plantations.

Post-fire soil water repellency under stones and forest residue mulch versus of bare soil

Abstract Soil water repellency (SWR) is commonly defined as a physical property of soil to resist wetting. Fire can induce, enhance, or reduce SWR and, consequently, lead to considerable changes in soil water infiltration and storage and increase soil erosion by water. The application of mulches to cover burned areas has been found to be an efficient emergency stabilization treatment. However, little is known about possible side effects on SWR, especially long-term effects. Under forests, SWR is known to be very heterogeneous, particularly in proximity to trees and shrubs, litter type and thickness, stones, cracks and roots. This study targeted the effects of post-fire mulching on SWR in a eucalypt plantation five years after a wildfire. The application of forest residue mulch did not significantly change SWR in bare soil patches or under stones, comparing the mulched and untreated plots. By contrast, SWR in the mulched plots was, significantly stronger under mulch than in bare soil. The same was true for both soil organic matter content (SOM) and soil moisture content (SMC), suggesting that SOM played a more important role than SMC. In turn, SWR under mulch was not significantly different from SWR under stone, while both SMC and SOM were significantly higher under mulch than stone. This could be explained by the differences in SMC overriding the effects of the differences SOM, or, alternatively, by possible differences in SOM quality, in particular of the “fresh” input from the mulch. Overall, the present results indicated that different mechanisms may drive SWR dynamics beneath mulch fragments, stones and bare soil patches. A better understanding of these mechanisms is important to improve the knowledge of post-fire overland flow generation and, thereby, to improve its prediction using hydrological models, especially during the early phases of the window-of-disturbance.

Contrasting Weather and Stocking Effects on Eucalyptus Initial Coppice Response in Brazil.

In Eucalyptus plantations, coppice rotations often yield less than initial rotations. The TECHS project (Tolerance of Eucalyptus Clones to Hydric, Thermal and Biotic Stresses) studied short rotation coppicing across a 3000 km gradient. The main objective of this work was to compare the survival, sprouting, and initial growth of Eucalyptus clones managed and to examine factors that might influence the productivity of the coppice rotation: climate, genotypes, and stocking. Eight of the TECHS sites spread from latitudes 6° S to 30° S were included in the coppice study, with 17 genotypes at each site. The initial rotation had been planted at a 3 m × 3 m spacing and also in a spacing trial at densities from 500 to 3500 trees ha-1. Six months after harvesting the initial Eucalyptus rotation, average survival was 88%, with tropical clones showing over twice the sprouting biomass (6.7 vs. 2.9 Mg ha-1) and four times the woody biomass compared to subtropical clones (4.7 vs. 1.1 Mg ha-1). Greater initial water deficits had stronger sprouting and growth. Clones with higher belowground carbon allocation in the initial rotation performed better in coppicing, and precipitation became more influential after 12 months. Drought and spacing trials significantly affected growth.

Melissopalynological study of Melipona (Eomelipona) torrida Friese, 1916: a native stingless bee from southern Brazil

Few data are on bee–plant interactions for the Melipona torrida bee in southern Brazil. This is a native bee vulnerable to extinction that pollinates native plants and produces honey that is especially appreciated by local populations. Aiming to evaluate the floral sources visited by Melipona torrida bee in southern Brazil a palynology investigation on honeys of this bee were carried out. Honeys were extracted each month from March 2020 to November 2021 of hives from two locations of Rio Grande do Sul (Cachoeirinha and Canoas). The 34 samples were analysed with a light microscope. In the honey samples of the Melipona torrida bee were identified 39 pollen types, principally tree plants. Melipona torrida bee visited frequently the plants of Myrcia type, Eucalyptus sp., Schinus terebenthifolia, Mimosa bimucronata, Parapiptadenia rigida, Morus nigra and Solanum sisymbrifolium. The pollen diagram show differences in pollen percentages throughout the year and CONISS grouped the samples in five groups (MT-1–MT-5). Richness of pollen types of samples was low in the months of winter and March and high in the honeys of months of Spring and Summer. The honeys were monofloral and heterofloral, and native plants were more visited than exotic species. The 33 pollen types from honey of Melipona torrida bee from southern Brazil can help in the knowledge of the bee–plant interaction of this native bee and propose appropriate plant management around the hives.

Combined transcriptomic, metabolomic and physiological analysis reveals the key role of nitrogen, but not phosphate and potassium in regulating anthocyanin biosynthesis induced by nutrient deficiency in Eucalyptus

Anthocyanin biosynthesis in Eucalyptus plants can be flexibly and rapidly modulated in response to hormones or environmental stimuli, including nutrient deprivation (ND). However, the underlying mechanism of ND in inducing anthocyanin biosynthesis in plants remains largely elusive. In this study, we discovered that anthocyanin levels in leaves and stems could well reflect nitrogen availability in Eucalyptus. Supplementation with nitrogen, but not with phosphate or potassium, effectively inhibited ND-induced anthocyanin biosynthesis. To further investigate how nitrogen regulates this process, comprehensive time-resolved transcriptomic and targeted metabolomic analyses were conducted. The results revealed that 3405, 2706, and 3153 genes were differentially regulated by nitrogen treatment at 1, 2, and 3 d, respectively. Pathway analysis indicated the majority of the enriched KEGG pathways were associated with cellular metabolism, such as amino acid and flavonoid biosynthesis. Moreover, metabolomic analysis showed that the most abundantly accumulated anthocyanins, cyanidin-3-O-galactoside and cyanidin-3-O-glucoside, along with key intermediates in the flavonoid pathway, were downregulated by nitrogen treatment. Furthermore, nitrogen-responsive MYB-bHLH-WDR complex genes were identified, including six EgrMYB113 family members. Overexpression of one of the EgrMYB113-like genes induced anthocyanin biosynthesis in the transgenic hairy roots of Eucalyptus. Interestingly, mutation of AtMYB113 inhibited nitrogen deficiency-induced anthocyanin biosynthesis in Arabidopsis, suggesting that MYB113 is a novel N-responsive MYB transcriptional regulator of anthocyanin biosynthesis. Additionally, nitrogen treatment upregulated a few GA biosynthesis genes while simultaneously downregulated the expression of several GA2ox genes. Exogenous application of GA3 decreased ND-induced anthocyanin biosynthesis. Conclusively, this study provides novel insights into the molecular mechanism of nitrogen in the regulation of anthocyanin biosynthesis in Eucalyptus.

Host location of gall parasitoids—A case study using the Quadrastichus mendeli–Leptocybe invasa system

AbstractGalls are thought to be induced by insects for protection, yet many gall‐forming insects experience heavy parasitization. Little is known about how parasitoids locate gall‐forming insects. Quadrastichus mendeli Kim & La Salle (Hymenoptera: Eulophidae) is an obligate ectoparasitoid of the larvae of Leptocybe invasa Fisher et La Salle (Hymenoptera: Eulophidae), which is an invasive gall‐forming pest in eucalyptus (Eucalyptus spp., Myrtaceae) plantations. In this study, Q. mendeli and L. invasa were used to explore parasitoid behavior when locating gall‐forming insects. Our results revealed that host location by Q. mendeli involved five discrete steps: walking, resting or grooming, antennating, probing and stinging. Antennation was the most frequent behavior, accounting for about half of the total time. Host location behavior of Q. mendeli occurred in the photophase. Female Q. mendeli exhibited a clear circadian rhythm: Almost all behaviors occurred during the photophase, and behavior peaked at the sixth hour of the light phase. The olfactory response rates of Q. mendeli to volatiles from galls decreased significantly after their antennae were detached. However, there was no significant difference in the host location behavior of Q. mendeli after their eyes were obscured. Our results provide essential information to explore the host location mechanisms in gall parasitoids.

Investigating the nexus of urban expansion, wetlands, and livelihoods from 1991 to 2021: evidence from Hawassa, Ethiopia

ABSTRACT Urban expansion in Ethiopia, particularly informal construction, has led to complex and dynamic changes in livelihoods and wetlands. This study examined the effects of urban expansion on the Cheleleka Wetland and the livelihood of the peripheral community in Hawassa. A mixed research design was used to quantitatively analyze Landsat imagery (1991, 2001, 2011, 2021) and socioeconomic data. Key informant interviews and focus group discussion data were narrated qualitatively. The built-up area substantially increased from 718.11 ha in 1991 to 4820.71 ha in 2021. However, agricultural and wetland areas decreased from 8807.58 ha and 8177.04 ha in 1991 to 6382.44 ha and 7030.26 ha in 2021, respectively. Water and forest areas fluctuated. Built-up areas had a significant advantage over other land use and cover classes, with agricultural, wetland, and forest areas being converted into built-up areas throughout the study period. As a result, the area of Lake Hawassa expanded. Currently, the Cheleleka Wetland has been negatively impaired by overgrazing, cutting of grass, animal dung dumps, eucalyptus plantations, agricultural expansion, and urban expansion. Urban expansion has exacerbated social and economic divisions, resulting in the concentration of poor-quality neighborhoods in the peripheral community. To protect the wetlands, alternative livelihoods and participatory land-use planning are crucial.

Exploring the diversity of leafrollers (Lepidoptera: Tortricidae) associated with eucalypts in South African forestry nurseries and plantations, with a new report of Strepsicrates sp.

A number of insect pests cause damage to eucalypts in South Africa. Their accurate identification is a key part of managing and controlling these pests. The aims of this study were to identify leafroller insect species in South African eucalypt nurseries and plantations, and to determine whether the species were native insects that had developed new host associations with eucalypts or introduced non-native species. A section of the mitochondrial cytochrome c oxidase subunit 1 (CO1) gene of multiple specimens from nurseries and plantations was sequenced. The sequence data were compared and validated using sequences available in BOLD systems and GenBank databases. Results revealed the presence of an introduced non-native Strepsicrates sp. in both nurseries and plantations. In addition, the native species Choristoneura occidentalis and Eccopsis incultana were confirmed as present in plantations only and the native species Lozotaenia capensana was confirmed as present in one of the nurseries. Eucalypts are reported as host plants of C. occidentalis, E. incultana and Lozotaenia capensana for the first time. The findings contribute valuable insights into the identification and diversity of leaf rollers in eucalypt plantations in South Africa, with potential implications for pest management.

Distribution patterns of Calonectria (Ascomycota, Sordariomycetes, Hypocreales, Nectriaceae) species complexes related to diseased leaves and soil habitats during leaf blight outbreak season in Eucalyptus plantations in southern China.

Calonectria leaf blight caused by Calonectria species is one of the most important diseases associated with Eucalyptus plantations in Asia and South America. This study aimed to clarify the distribution patterns of Calonectria species residing in different species complexes associated with diseased trees and soils during leaf blight outbreak season in Eucalyptus plantations in southern China. In this study, 482 Calonectria isolates obtained from diseased Eucalyptus trees and soils under these trees in eight sampling sites in three provinces were identified by DNA sequence analyses of tef1, tub2, cmdA, and his3 gene regions. Six species residing in three species complexes were identified: Calonectriapseudoreteaudii and C.acaciicola in the Calonectriareteaudii species complex; C.hongkongensis, C.aconidialis, and C.chinensis in C.kyotensis species complex; and C.auriculiformis in C.cylindrospora species complex. The habitats of Calonectria in different species complexes differed, C.reteaudii species complex inhabits in both diseased trees and soils, C.kyotensis species complex only in soils. The Calonectria leaf blight in the sampled regions was caused by species in the C.reteaudii species complex but not by the species in the C.kyotensis species complex. These findings suggest that the species in the C.reteaudii species complex should receive more attention in disease management, as they are the primary cause of the disease in the sampled regions.

Whole-Genome sequencing of Calonectria dianii: An important pathogen causing Eucalyptus leaf blight

Eucalyptus leaf blight, caused by Calonectria spp., significantly impacts the global Eucalyptus industry. Calonectria dianii, as one of the predominant causal agents, poses a serious threat to Eucalyptus plantations in China. To enhance our understanding of its pathogenic mechanisms, we sequenced the genome of C. dianii RIFT 6520 using both Nanopore PromethION and Illumina NovaSeq PE150 platforms. Our analysis revealed a 61.76 Mb genome comprising 30 contigs with an N50 of 4,726,631 bp, a GC content of 49.74 %, and 10,184 predicted coding genes. Additionally, comparative genomic analysis between C. dianii and seven other significant plant-pathogenic Calonectria species was conducted. This analysis provided insights into the evolutionary relationships and adaptive mechanisms of these pathogens. Our study elucidates the genetic basis of C. dianii's pathogenicity and evolution, providing valuable information for future research on its molecular interactions with Eucalyptus and aiding in the development of precise control measures for Eucalyptus leaf blight.

Evaluation of Automated Object-Detection Algorithms for Koala Detection in Infrared Aerial Imagery.

Effective detection techniques are important for wildlife monitoring and conservation applications and are especially helpful for species that live in complex environments, such as arboreal animals like koalas (Phascolarctos cinereus). The implementation of infrared cameras and drones has demonstrated encouraging outcomes, regardless of whether the detection was performed by human observers or automated algorithms. In the case of koala detection in eucalyptus plantations, there is a risk to spotters during forestry operations. In addition, fatigue and tedium associated with the difficult and repetitive task of checking every tree means automated detection options are particularly desirable. However, obtaining high detection rates with minimal false alarms remains a challenging task, particularly when there is low contrast between the animals and their surroundings. Koalas are also small and often partially or fully occluded by canopy, tree stems, or branches, or the background is highly complex. Biologically inspired vision systems are known for their superior ability in suppressing clutter and enhancing the contrast of dim objects of interest against their surroundings. This paper introduces a biologically inspired detection algorithm to locate koalas in eucalyptus plantations and evaluates its performance against ten other detection techniques, including both image processing and neural-network-based approaches. The nature of koala occlusion by canopy cover in these plantations was also examined using a combination of simulated and real data. The results show that the biologically inspired approach significantly outperformed the competing neural-network- and computer-vision-based approaches by over 27%. The analysis of simulated and real data shows that koala occlusion by tree stems and canopy can have a significant impact on the potential detection of koalas, with koalas being fully occluded in up to 40% of images in which koalas were known to be present. Our analysis shows the koala's heat signature is more likely to be occluded when it is close to the centre of the image (i.e., it is directly under a drone) and less likely to be occluded off the zenith. This has implications for flight considerations. This paper also describes a new accurate ground-truth dataset of aerial high-dynamic-range infrared imagery containing instances of koala heat signatures. This dataset is made publicly available to support the research community.

Impact of Skidding and Slope on Grapple Skidder Productivity and Costs: A Monte Carlo Simulation in Eucalyptus Plantations

Background: In the context of mechanized timber harvesting, alterations in technical parameters, such as skidding distance and terrain slope, have the potential to influence the productivity and production costs associated with the self-propelled grapple skidder. Furthermore, these variables are inherently uncertain, which could potentially cause forest managers to make inaccurate decisions. The objective was to analyze whether four skidding distances and two slope classes influence the productivity and production costs of the grapple skidder in Eucalyptus planted forests from a stochastic perspective using the Monte Carlo method. Methods: Productivity was estimated using the time study protocol. To calculate the cost per scheduled hour of the grapple skidder, both fixed and variable costs were considered, and subsequently, the production cost was determined. Results: The mean productivity of the grapple skidder on flat slopes was 114.35 m3 h−1, while on wavy to strong wavy slopes it was 80.43 m3 h−1. In flat slopes, considering all skid distance ranges, the mean production cost was 0.82 USD m−3, while in wavy to strong wavy slopes it was 1.48 USD m−3. The mean values for operator labor costs and fuel account for 58.1% of the cost per scheduled hour of the grapple skidder. Conclusions: The mean productivity of the grapple skidder in Eucalyptus planted forests decreased with increasing skidding distance in both slope classes but was 29.7% lower on wavy to strong wavy slopes compared to flat slopes. The mean production cost of the grapple skidder during timber skidding on flat slopes is 80.0% lower than on wavy to strong wavy slopes. For future investigations, the impact of other slope classes, skid distances, and silvicultural aspects on productivity and production costs can be considered from a stochastic perspective using the Monte Carlo method.