Oak Forests Research Articles

Taxonomic indicators and vital status of Quercus robur L. in different forest conditions of the mouth and middle part of the ravine Yatsevo (Dnipropetrovsk region)

The influence of forest and vegetation conditions on the taxonomic characteristics and vital state of the common oak (Quercus robur L.) was analyzed. The research was conducted on four experimental plots in the Yatsevo tract: in the thalweg (CL3) and on the lower third of the slope (CL2) of the southern exposure of the mouth part and in the thalweg (CL3) and the upper third of the slope (CL1-2) of the same exposure in the middle part of the gully. In the thalweg of the middle part of the gully, a linden-pack oak forest with elm grows, the density of this stand (1700 pcs./ha) is the largest among the studied phytocoenoses. On the rest of the experimental plots, elm-pack oak forests grow with a density of 917 to 1150 pcs./ha. The average values of the main taxonomic parameters (height, diameter, cross-sectional area, and reserve) practically do not differ in Q. robur plants growing in the thalweg (CL3) and the lower third of the slope (CL2) of the mouth part of the tract. These indicators in thalweg plants (CL3) of the middle part of the gully are the highest among all experimental variants, and in individuals of the upper third of the slope (CL1-2) - are the lowest. In all studied hygrotopes, healthy trees prevail, with weakened individuals taking the second place by the number of individuals. The vital status index (Ln) shows that the thalweg stands in both the mouth and middle parts of the gully are healthy (Ln 86.3 and 84.3, respectively). The stands of the lower third of the slope (CL2) of the mouth part of the tract and the upper third of the slope (CL1-2) of the middle part are somewhat weakened (Ln 76.9 and 76.7). The pathologies of the crown and trunk of Q. robur trees in the experimental plots were analyzed. It was found that hygromesophilic conditions (CL3) are preferable for the formation of healthy stands.

Microbial community and enzyme activity respond differently to seasonal and edaphic factors in forest and grassland ecosystems

Although microbial community and function patterns have been extensively studied, little is known about whether the patterns are consistent in different ecosystems and how they are influenced by seasonality or other environmental factors. To test the driving factors of microbial communities and potential functions, we collected soil samples from five forests (mixed broadleaved-Korean pine forest, mixed pine and oak forest, deciduous broadleaved mixed forest, subtropical evergreen broad-leaved forest and tropical rainforest) and three grassland ecosystems (meadow steppe, semi-arid grassland and arid grassland) across China in three seasons (spring, summer and autumn). Microbial diversity based on the sequencing of 16S rRNA gene for bacteria and internal transcribed spacer (ITS) genes for fungi were measured, and potential functions represented by soil extracellular enzyme activities (EEAs) were analyzed. The results found that soil EEAs were significantly higher in summer than in spring and autumn, and both bacterial and fungal richness indices showed greater seasonal fluctuations than the diversity. Fungal richness indices were highest in summer in both forest and grassland ecosystems, while the lowest were observed in spring for forest and in autumn for grassland, respectively. In addition, fungal communities were closely related to ecosystem types, while bacterial communities were not significantly different across ecosystems and exhibited a broader habitat niche breadth, but the relative abundance of dominant bacterial phyla showed stronger correlations with environmental variables (including climate, soil properties and nutrients) in grassland than in forest ecosystems. The decoupling of microbial community and EEAs was observed in both forest and grassland ecosystems, indicating the function redundancy of soil microorganisms. The present study provided crucial information about the effects of ecosystem types, seasonality and edaphic factors on soil microbial communities and EEAs, and could advance the understanding of soil potential function responses to environmental changes.

Classification of Caucasian oak (Quercus macranthera) forests from Dagestan (Eastern Caucasus)

Classification of Caucasian oak (Quercus macranthera) forests from Dagestan (Eastern Caucasus)

Tardigrade diversity and community composition across Norwegian boreal forests

Abstract Tardigrades are common in many terrestrial environments and habitats. Although little is known on their ecological preferences, previous studies found diversity and community composition significantly affected by various variables. This study associated tardigrade species’ records with climatic variables, forest type, and substrate categories exploring tardigrade diversity and species communities to find associations with ecological characteristics of Norwegian forests. A total of 17 473 specimens were identified, encompassing 131 species (including putatively new species) from 305 samples of different substrates (leaf litter, bryophytes, and lichens). Bryophytes and lichens of samples were classified according to the main species, and growth form, and associated with tardigrade species and sample metadata. Tardigrade species’ richness was related to climatic variables and forest type, increased with precipitation, decreased with summer temperature, and not varied with precipitation seasonality. Although there was an unbalanced representation of substrate categories in the different forest types, some tendencies were detectable. Mixed oak and birch forests reached the highest species’ richness. Tardigrade community composition varied between substrate categories and, to a lesser degree, between forest types, but not with climatic variables. Our study highlights the importance of large-scale variables on tardigrade diversity, and substrate categories for tardigrade community composition.

Above and belowground carbon stock of pine plantations and native oak forests coexisting in central Spain

Above and belowground carbon stock of pine plantations and native oak forests coexisting in central Spain

Predicting the potential ecological niche distribution of Slovenian forests under climate change using MaxEnt modelling

The aim of the article is to assess the potential impacts of climate change on Slovenian forests in the period 2080–2100 based on two climate scenarios: SSP1-2.6 (optimistic) and SSP5-8.5 (pessimistic) using the MaxEnt software. Slovenian forests are divided at the ecological community level into thirteen forest vegetation types. Analyses of changes in ecological niche areas, distances of vectors between centroids of present areas and future ecological niches, and general spatial changes are carried out. In addition, changes in the altitudinal zones of forest vegetation types were investigated. The results indicate significant changes for Thermophilous beech forests and Thermophilous hop-hornbeam, sessile oak, downy oak, Scots pine and black pine forests. The potential changes in the altitudinal zones of forest vegetation types indicate a clear trend of forest vegetation types moving to higher altitudinal zones.

A Millennial‐Scale Oscillation in Latitudinal Temperature Gradients Along the Western North Atlantic During the Mid‐Holocene

AbstractChanges in vegetation in North America indicate Holocene shifts in the latitudinal temperature gradient along the western margin of the North Atlantic. Tree taxa such as oak (Quercus) and birch (Betula) experienced opposing directions of change across different latitudes consistent with changes in temperature gradient steepness. Pollen‐inferred temperatures from 34 sites quantify the gradient changes and reconstruct a long‐term northward steepening in summer and southward steepening in winter. From 4.8 to 3.8 ka, an oscillation in tree distributions interrupted the long‐term trends as a steep temperature gradient developed north of 43.5°N. The shift likely limited cold outbreaks to the south, producing anomalously high summer temperatures at 42–43.5°N, and enabling a northward expansion of oak forests. The forest and temperature gradient changes appear consistent with orbital and ice sheet forcing as well as millennial variability in the North Atlantic pressure field analogous to the North Atlantic Oscillation on interannual time scales.

Pedunculate oak (Quercus robur L.) in Bosnia and Herzegovina – state and perspectives

Bosnia and Herzegovina is located in Southeast Europe, and more than half its area of 51.129 km² belongs to forests and forest lands. Our forests have a plenty of species, especially endemic, a great diversity of plant communities, and 93% of natural forests. We have eight oak species growing in Bosnia and Herzegovina. The most important are Quercus robur (despite being almost extinct due to over-exploitation during the late XIX and early XX century), and Quercus petraea. Quercus pubescens and Quercus cerris are also ecollogicaly crucial.
 Today in Bosnia and Herzegovina, pedunculate oak is found in mixed stands with common hornbeam and in pure stands under exceptional conditions, with the total area of about 30.000 ha. 
 The area of Bosnia and Herzegovina is the central part of the natural southern distribution of pedunculate oak. Because of that, it has a specific genetic structure and builds a connection of the south and east Balkan Peninsula provenances with the provenances of Central Europe and has a crucial role in gene movement from north to south and vice versa, and west to east and vice versa.
 According to the Ecological-vegetation regionalization of Bosnia and Herzegovina, forests of pedunculate oak and common hornbeam are potential vegetation on about 5% of the country's territory. It means that there are possibilities for the reintroduction of these valuable species, and it is necessary to work on its reintroduction to suitable habitats. Research indicates that it is a species with a potential for adaptation on climate change. Our research results showed that the remaining pedunculate oak populations in Bosnia and Herzegovina have a good genetic structure and can be used as a seed stands for collecting seed material and producing seedlings for afforestation with this species.

Using the Alternative Stable States Framework to understand the persistence of secondary shrubland within a Mexican oak forest with livestock and agricultural legacies

Many forests exist in human-modified mosaic landscapes subject to logging, agriculture, and livestock grazing. These disturbances can reduce ecosystem resilience and ultimately result in crossing thresholds, leading to the transition of the ecosystem into new stable states with different plant communities. The interaction between these disturbances and forest succession is still poorly understood, despite the growing need to manage these human-modified landscapes for biodiversity and productivity. We studied abrupt changes in vegetation composition in a Central Mexican oak forest and explored how these changes could indicate the coexistence of various alternative stable states caused by agricultural and livestock legacies. We established 36 strip transects covering 9000 m2 in patches with various land use legacies where we sampled vegetation, soil characteristics, and human disturbance. We assessed future and past tendencies in vegetation spatial patterns by evaluating seedling composition and analyzed time series of NDVI signals recorded by LANDSAT images (1972–2019). We utilized NMDS, PERMANOVA, and ANOVA analyses to assess if stable states can be distinguished based on historical and current variations in vegetation composition and structure in patches with different management legacies. We then assess potential factors that may contribute to differences in plant community composition by fitting edaphic, topographic, and anthropogenic disturbance variables to the ordination analyses.We identified three distinct plant communities: oak forest (dominated by late-successional Oak species), secondary shrubland (dominated by Vachellia-Dodonaea association), and a transitional forest-shrub community (a mixture of the first two communities). Time-series analyses and seedling composition provide evidence of long-term community segregation. Variation partition analysis demonstrated that anthropogenic disturbance (particularly livestock browsing), had a greater impact on species composition differentiation than environmental variables.A state-and-transition model is proposed, where cattle browsing and agricultural legacies trigger the transition from oak forests to a stable secondary shrubland community. Three potential self-reinforcing and interacting feedbacks are suggested: (i) micro-environmental filtering, (ii) plant-trait mediated assembly process, and (iii) cascading effects on tree recruitment caused by cattle browsing. The proposed state-and-transition model explains forest successional dynamics in systems with multiple anthropogenic disturbances and provides a conceptual framework for understanding and guiding successional trajectories.

What burned the forest? Wildfires, climate change and human activity in the Mesolithic – Neolithic transition in SE Iberian Peninsula

Climate variability such as higher or lower temperatures, changing precipitation patterns, shifts in plant communities and other climate-related changes have particularly affected areas with Mediterranean-type climates. A multi-proxy analysis including pollen, sedimentary charcoal, mineralogy and Summed Probability Distributions (SPD) of archaeological 14C dates, allowed the reconstruction of landscape change, geomorphological evolution and fire history at the Laguna de Villena, in the southeastern Iberian Peninsula, during the Mesolithic-Neolithic transition. The Villena paleolake was sensitive to Early Holocene and Middle Holocene regional climatic variability that included several arid phases (around 8.2 ka cal BP, 6.8 ka cal BP and 5.9 ka cal BP) according to geochemical and pollen data. During this period, landscape dynamics show the degradation of oak forests and expansion of pyrophytic pine forests and shrublands, as well as open spaces predominated by grasses. The charcoal record shows a decreasing trend of biomass burned from 8.5 ka cal BP onwards, although fire peaks occurred recurrently during the Early and Middle Holocene. The most intense phase of fire activity was experienced in the last millennia of the Early Holocene, with five fire episodes from 9.1 to 8.4 ka cal BP, coinciding with a phase of higher archaeological evidence in the area. A decrease in archaeological evidence coincides with a gap in fire episodes during the Early Holocene-Middle Holocene transition, suggesting an effect of the abrupt 8.2 ka cal BP event on human activity and on landscape dynamics. After 8.0 ka cal BP, lowerer biomass burned is explained by the configuration of a more open landscape due to the combination of climate (increasing aridity) and increasing human activities in the region. The mineralogical and palynological data highlighted the interaction between human activities, climate and fire dynamics. The sedimentary charcoal record evidenced how most of the fire peaks did not occur in the context of dry episodes, as often assumed, deriving on an anthropogenic explanation related to Early and Late Mesolithic burning practices during a phase of higher archaeological evidence in the Villena paleolake surroundings. Afterwards, combined agropastoral activities from the Early Neolithic onwards and increasing aridity during the Middle Holocene maintained the forest clearances, in the context of fire episodes characterised by decreased biomass burned. This study shows how Middle Holocene palaeoecological records reflect complex histories blending climate and anthropogenic processes that derived in major landscape changes explaining the origin of current landscapes.

Elucidating factors driving post-fire vegetation recovery in the Mediterranean forests using Landsat spectral metrics

Wildfires represent one of the primary disturbance agents in the Mediterranean, significantly affecting the ecological integrity of forests. Therefore, understanding the spatial patterns of post-fire vegetation recovery is crucial to improving forest restoration planning and assessing the regeneration capacity of different forest stands that have been impacted by wildfires. In this study, we analysed post-fire vegetation recovery rates within the context of fire severity, pre-fire vegetation, and post-fire climate conditions, for different Mediterranean forest classes, namely, Mediterranean pine, holm, deciduous oak forests, sclerophyllous vegetation, and thermophilous shrublands. Basilicata, in Italy, was chosen as a study area, as it represents a wide range of forests.The Relative Recovery Indicator (RRI) was derived from Normalized Burn Ratio (NBR) patterns extracted from 30-meter Landsat time series for different wildfires that occurred during the 2004–2016 within Google Earth Engine (GEE) environment. A Linear Mixed Model (LMM) was used to test the effect of the different variables on the RRI. Results showed a general decrease in recovery rate within five-years post-fire for each forest cover class, which is mainly related to pre- and post-fire conditions. Pre-fire vegetation conditions significantly influenced post-fire vegetation recovery, especially in sclerophyllous and deciduous oak forests. Post-fire climate conditions (e.g., temperature) were also important predictors of vegetation recovery explaining the variation in post-fire RRI patterns. The proposed method could provide new insights into the restoration and management of forest ecosystems in the Mediterranean.

Economically optimised target state of uneven-aged forest management for main forest types in Slovakia

Abstract The study presented a bioeconomic modelling approach for an uneven-aged mixed forest management planning. Regression models for transition (increment), and ingrowth (regeneration) used the National Forest Inventory (NFI) of Slovakia and regional inventory data. Mortality was based on salvage logging records. Models were specific for five tree species within three forest types (FT) (oak with hornbeam and beech, beech, mixed fir-beech-spruce). Net timber prices were calculated with regard to stem quality. Tree growth depended on crown characteristics. The regression models were adjusted to three main geobiotope (GBT) sites per FT. Forest growth was simulated with the density-dependent stand-level matrix transition model. Financial optimisation of harvest was sensitive to an interest rate. Long-time optimisation stabilised in a steady state equilibrium characterised by a stable diameter distribution. Target diameters were specific for site and tree species, and were highest for fir, a dense crown, a good stem quality, and a lower interest rate. Standing timber volume varied from 150 m3 ha–1 (oak forests, 2% interest rate) to 400 m3 ha–1 (beech and fir-beech-spruce forests, 0.5% interest rate). Harvested volume varied from 38 to 93 m3 ha–1 per 10 years, stand basal area (ba) varied from 19 to 36 m2 ha–1 depending on the site, timber price, and interest rate. The discussion pointed out that the relative low volume of the oak FT resulted from the light-demanding characteristics of oak. The mean of oak mosaic structures was lower compared to the high level of more storeys present in the single tree selection structures in beech and mixed fir-beech-spruce forests.

A Quantitatively Divided Approach for the Vertical Belt of Vegetation Based on NDVI and DEM—An Analysis of Taibai Mountain

Vertical vegetation differentiation is the most important form of spatial pattern in mountainous areas. It is of great significance to accurately divide vegetation into vertical zones for the study of mountain ecosystems and ecological protection. In order to accurately divide the vertical zone of mountain vegetation and determine the spatial distribution of mountain vegetation, the relationship between the vegetation index of various vegetation types and altitude was examined using remote sensing and geographic information technology. Taking Taibai Mountain, the main peak of the Qinling Mountains in China, as the study area, based on the difference in NDVI between summer and autumn (DNSA), this work constructed a DEM-NDVI scatter plot and quantified the boundary of the vertical zone by the half-peak width calculation method. The findings showed that: (1) the vertical distribution pattern of mountain vegetation may very well be reflected in the scatterplot that NDSA and DEM created; (2) Six vertical belts could be accurately identified to the meter level on Taibai Mountain’s south slope. Up to the altitude, the oak forest zone from the bottom of the mountain to the elevation of 1919 m, the pine-oak mixed forest zone is distributed in 1919–2331 m, the birch forest is distributed in 2115–2585 m, the fir forest is distributed in 2516–3150 m, the redwood forest is distributed in 3109–3551 m, and the alpine scrub meadow is distributed in 3551 m to the peak. On the north slope, 1053–2087 m above sea level is oak forest, 2087–2693 is birch forest, 2562–3006 is fir forest, 2987–3513 m is redwood forest, and 3513 to the top of the mountain is alpine scrub meadow; and (3) the distribution pattern of the vegetation vertical belt on the DEM-NDVI scatter plot was essentially compatible with the vegetation classification results derived from remote sensing images. The DEM-NDVI scatter plot can reflect the average distribution of vegetation population and can more accurately express the characteristics of vegetation vertical zone changes with altitude.

Биоэкологическая характеристика уникальных природных и искусственных популяций дуба на полупустынных ландшафтах Волгоградской области

Биоэкологическая характеристика уникальных природных и искусственных популяций дуба на полупустынных ландшафтах Волгоградской области

Morphological and Molecular Characterization of Ectomycorrhizas of Phylloporus (Boletales) and Quercus sapotifolia from Tropical Oak Forest of Eastern Mexico

Morphological and Molecular Characterization of Ectomycorrhizas of Phylloporus (Boletales) and Quercus sapotifolia from Tropical Oak Forest of Eastern Mexico

Biotic Factors Drive Woody Plant Species Diversity across a Relative Density Gradient of Quercus aliena var. acuteserrata Maxim. in the Warm–Temperate Natural Oak Forest, Central China

Woody plants are crucial components of forest ecosystems and play critical roles in regulating community succession and ecosystem function. Studying woody plant diversity and its influencing factors is thus important for understanding and protecting forest ecosystems. Quercus aliena var. acutiserrata is an important deciduous broadleaf species in the warm–temperate forest of central China. Multiple regression and structural equation modelling were used to discuss the effect of biotic and soil factors on tree species diversity across seven relative density gradients of Q. aliena var. acutiserrata trees in this zone. Our results showed that the following: (1) Species diversity showed significant decreasing trends with increasing relative density of Q. aliena var. acutiserrata. (2) As the relative density of the oak tree increased, some biotic factors (canopy density, and mean DBH) and soil factors (Soil SOC, AP, and AK) all showed significantly increasing trends, whereas the DBH variation (CVD) and soil pH displayed decreasing trends. (3) Biotic factor (e.g., mean DBH, CVD, and competition interaction) had strong direct effect on species diversity, and soil factors exerted indirect roles on tree diversity via biotic factors. Our results provide insight into biodiversity protection and scientific management in this warm–temperate natural oak forest.

Heat Budget of Sub-Mediterranean Downy Oak Landscapes of Southeastern Crimea

This article presents the findings of a research endeavor focused on the diurnal and seasonal dynamics of heat balance and its constituent elements within an oak forest situated in the expanse of the Karadag Nature Reserve. Computed are the values corresponding to the elements of heat balance, encompassing radiation balance, latent heat fluxes corresponding to heat consumption for evaporation, turbulent heat exchange transpiring within the atmosphere, and heat flux coursing through the soil. The features of changes in the heat balance in two key areas are considered: in the zone of growth of the downy oak forest in an open area and in the forest itself. The study discloses patterns characterizing the apportionment of radiation balance into heat and energetic fluxes within the context of the downy oak landscapes native to the southeastern Crimea. Scrutiny of the data established that a substantial proportion of radiation balance finds application in propelling turbulent heat flux, while a minor share is channeled into processes of evaporation and soil heat flux. Evidenced is that the magnitudes of heat balance components, encompassing radiation balance, latent heat fluxes corresponding to heat consumption for evaporation, turbulent heat exchange transpiring within the atmosphere, and heat flux through the soil within the sub-canopy realm, undergo modifications contingent upon the seasons of the year and the vegetative phases of the downy oak forest. The correlation between air temperature and the constituents of heat balance is subject to analysis both within the confines of the territory in the zone of growth of the downy oak forest in an open area and in the forest itself. Manifest is the constancy of the influence exerted by forest vegetation upon heat balance; nevertheless, the degree of its impact is circumscribed by the cyclical dynamics of foliage upon the trees: a well-developed canopy serves to amplify the influence exerted upon the distribution of heat and energetic fluxes. This study of heat balance and its constituents assumes significance in engendering comprehension regarding the operation of downy oak landscapes that are situated on the periphery of their habitudinal range. Also, it helps to reveal deeper patterns of climate change in forest ecosystems.

Ecological and biological features and nectariferous value of elm trees

Bee pasturages and natural-climatic conditions in the forest fund of the steppe Pridonye are characterized by great variability. Plantations of European white elm, Scotch elm and English elm occupy 2.2% of the area of the steppe Pridonye. The purpose of this study was to identify honey-bearing species by the forest phytocenosis components in ravine elms and floodplain forests and to determine the honey productivity of plant formations. Accepted methods of scientific research in beekeeping were utilized. The silvicultural and taxational characteristics of the forest stand were obtained, the species composition of the honey-bearing flora was specified and the honey productivity by forest types was determined. Honey productivity of the plant formation of ravine elms is 106.4–203.3 kg/ha. European white elm (Ulmus laevis) provides honey productivity of 32.9 kg/ha in the forest phytocenosis on the shady banks of the ravine oak forests. Field maple (Acer campestre) contributes to this significant index (203.3 kg/ha) in the stand composition on high and steep gully slopes. On the light banks honey production is characterized by honey-bearing undergrowth species, which are found mainly in forest glades and woodsides, as well as the carpet plants representatives. In elm-herbage-nettle-blackberry floodplain forests, the main honey yield (35.3 kg/ha) is given by European white elm and white willow (Salix alba), while in the undergrowth it is given by common buckthorn (Rhamnus cathartica), alder (R. alnus), and European cranberry bush (Viburnum opulus). Skillful use of the honey-bearing potential of forest plants not only makes it possible to successfully develop beekeeping, but also to ensure a significant increase in the forest fund of the southern regions of the European part of the Russian Federation.

Comparison of two enthalpic models for the thermodynamic characterization of the soil organic matter in beech and oak forests

The thermodynamic characterization of the soil organic matter could be achieved by different enthalpic models little explored for soil. This paper compares two of them for calculating the enthalpy change, the Gibbs energy change and the entropy change of the soil organic matter combustion reaction, by simultaneous differential scanning calorimetry and thermogravimetry. Soil samples were collected in beech and oak forests from different geographical areas, and at different depths to represent the L/F horizon and the mineral soil, at each sampling site. The thermodynamic state variables were calculated using two different enthalpic models, to examine how they differed in relation to different types of SOM and different forest ecosystems. Both models yielded thermodynamic variables, which although closely and significantly correlated, were statistically significantly different. All the thermodynamic variables depended on the different forest types and the different nature of the soil organic matter under study. Results allowed to discern which of the models applied better to the SOM combustion reaction designed.

Predator odor can reduce acorn removal by granivorous rodents in mixed oak forest stands

Developing better practices for rodent pest control is of high importance to reduce damage during forest restoration and in crop production. For example, during direct seeding with large and highly attractive seeds such as acorns, most seeds will disappear due to consumption or dispersal if not protected. An unexplored concept in reducing rodent damage is the use of repellents derived from predators. We tested the efficiency of three volatile compounds (2-propylthietane, 2-phenylethylamine and indole) associated with predators as rodent repellent candidates and scored the reduction of acorn (Quercus petraea) removal at two field sites in southern Sweden. We further investigated at what distance (5 cm, 10 cm, and 15 cm) from the odor source the odors were efficient in lowering the removal of acorns. Removal was lowest with 2-propylthietane (25–45 % of acorn removal), followed by 2-phenylethylamine (75–95% acorn removal) at 5 cm. Indole failed to decrease acorn removal and did not differ significantly from the control treatments. In the control treatments, almost all acorns (95–100%) were removed from the plots during the 48-hour sessions at both sites, and the acorns were removed faster than in the other treatments. Removal increased with distance from the 2-propylthietane odor dispenser at both field sites. Here, the lowest acorn removal occurred at 5 cm from the odor disperser. Our short time experiment shows for the first time the potential of using 2-propylthietane for short-term protection of acorns from foraging by granivorous rodents in oak woodlands. To help increase the reliability of direct seeding as a method for regenerating and restoring forests, future studies should investigate whether the range and longevity in the field of predator odor formulations can be improved.