Woodland Conservation Research Articles

Airborne castanea pollen forecasting model for ecological and allergological implementation

Castanea sativa Miller belongs to the natural vegetation of many European deciduous forests prompting impacts in the forestry, ecology, allergological and chestnut food industry fields. The study of the Castanea flowering represents an important tool for evaluating the ecological conservation of North-Western Spain woodland and the possible changes in the chestnut distribution due to recent climatic change. The Castanea pollen production and dispersal capacity may cause hypersensitivity reactions in the sensitive human population due to the relationship between patients with chestnut pollen allergy and a potential cross reactivity risk with other pollens or plant foods. In addition to Castanea pollen's importance as a pollinosis agent, its study is also essential in North-Western Spain due to the economic impact of the industry around the chestnut tree cultivation and its beekeeping interest. The aim of this research is to develop an Artificial Neural Networks for predict the Castanea pollen concentration in the atmosphere of the North-West Spain area by means a 20years data set.It was detected an increasing trend of the total annual Castanea pollen concentrations in the atmosphere during the study period. The Artificial Neural Networks (ANNs) implemented in this study show a great ability to predict Castanea pollen concentration one, two and three days ahead. The model to predict the Castanea pollen concentration one day ahead shows a high linear correlation coefficient of 0.784 (individual ANN) and 0.738 (multiple ANN). The results obtained improved those obtained by the classical methodology used to predict the airborne pollen concentrations such as time series analysis or other models based on the correlation of pollen levels with meteorological variables.

Climate change and the distribution and conservation of the world's highest elevation woodlands in the South American Altiplano

Climate change is becoming an increasing threat to biodiversity. Consequently, methods for delineation, establishment and management of protected areas must consider the species' future distribution in response to future climate conditions. Biodiversity in high altitude semiarid regions may be particularly threatened by future climate change. In this study we assess the main environmental variables that best explain present day presence of the world's highest elevation woodlands in the South American Altiplano, and model how climate change may affect the future distribution of this unique ecosystem under different climate change scenarios. These woodlands are dominated by Polylepis tarapacana (Rosaceae), a species that forms unique biological communities with important conservation value. Our results indicate that five environmental variables are responsible for 91% and 90.3% of the present and future P. tarapacana distribution models respectively, and suggest that at the end of the 21st century, there will be a significant reduction (56%) in the potential habitat for this species due to more arid conditions. Since it is predicted that P. tarapacana's potential distribution will be severely reduced in the future, we propose a new network of national protected areas across this species distribution range in order to insure the future conservation of this unique ecosystem. Based on an extensive literature review we identify research topics and recommendations for on-ground conservation and management of P. tarapacana woodlands.

Desde el cámbium hasta el bosque: evaluando las respuestas de Juniperus thurifera L. a los condicionantes ambientales y antrópicos a múltiples escalas

Olano, J.M., Rozas, V. 2015. From cambium to woodland: analyzing Juniperus thurifera L. response to environmental constraints at multiple scales. Ecosistemas 24(2): 60-68. Doi.: 10.7818/ECOS.2015.24-2.09. Juniperus thurifera L. (Cupressaceae) is a dioecious tree inhabiting the Western Mediterranean Basin in areas under Mediterranean continental climate. Spain (95.1%) and Morocco (4.8%) host the largest populations. Diverse dendroecological research developed during the last years has improved our knowledge about this species functioning and its forest dynamics. This review approaches the advances produced on several topics including xylogenesis, climate forcing of secondary growth and xylem anatomy, regional variability on climate control, water-use efficiency, non-structural carbohydrates dynamics and present and future dynamics of its Iberian forests. A special point is paid on sex-related differences between male and female junipers, including non-structural carbohydrate accumulation patterns, secondary growth and response to summer drought, the main climatic factor limiting growth. This review aims to synthesize the available knowledge about this species at multiple spatio-temporal scales, being particularly useful for researchers and managers interested in the investigation, management and conservation of Iberian Juniperus thurifera woodlands.

Stand competition determines how different tree species will cope with a warming climate.

Plant-plant interactions influence how forests cope with climate and contribute to modulate species response to future climate scenarios. We analysed the functional relationships between growth, climate and competition for Pinus sylvestris, Quercus pyrenaica and Quercus faginea to investigate how stand competition modifies forest sensitivity to climate and simulated how annual growth rates of these species with different drought tolerance would change throughout the 21st century. Dendroecological data from stands subjected to thinning were modelled using a novel multiplicative nonlinear approach to overcome biases related to the general assumption of a linear relationship between covariates and to better mimic the biological relationships involved. Growth always decreased exponentially with increasing competition, which explained more growth variability than climate in Q. faginea and P. sylvestris. The effect of precipitation was asymptotic in all cases, while the relationship between growth and temperature reached an optimum after which growth declined with warmer temperatures. Our growth projections indicate that the less drought-tolerant P. sylvestris would be more negatively affected by climate change than the studied sub-Mediterranean oaks. Q. faginea and P. sylvestris mean growth would decrease under all the climate change scenarios assessed. However, P. sylvestris growth would decline regardless of the competition level, whereas this decrease would be offset by reduced competition in Q. faginea. Conversely, Q. pyrenaica growth would remain similar to current rates, except for the warmest scenario. Our models shed light on the nature of the species-specific interaction between climate and competition and yield important implications for management. Assuming that individual growth is directly related to tree performance, trees under low competition would better withstand the warmer conditions predicted under climate change scenarios but in a variable manner depending on the species. Thinning following an exponential rule may be desirable to ensure long-term conservation of high-density Mediterranean woodlands, particularly in drought-limited sites.

Socio-economic factors affecting the conservation of natural woodlands in Central Riyadh Area – Saudi Arabia

This study aimed to identify some socioeconomic factors affecting local people in central Riyadh area for the utilization of wood and other energy sources in cooking and heating in order to develop some recommendations for conserving woodlands. The study results revealed that gas is the most common energy source used for cooking with a mean usage level of 2.79 (SD=0.58). On the other hand, wood ranked first for heating with the highest mean, usage level of 1.90 (SD=1.06). However, electricity and gas as sources of energy for heating ranked second and third with mean usage level of 1.81 and 0.80 respectively. The study revealed that local people with the university education were significantly making higher use of electricity for both cooking and heating and those with no formal education ranked the highest on wood use for both cooking and heating. In addition, those living in traditional houses significantly used more wood for cooking than those living in villas and apartments. Also, local people with high income levels significantly were using more electricity for heating than others. The study recommended conducting extension and environmental awareness raising programs to enhance local residents’ adoption of wood substitutes, promoting employment opportunities for unemployed locals, and subsidizing prices of alternative energy sources.

Residents’ preference and willingness to conserve homestead woodlands: Coastal villages in Okinawa Prefecture, Japan

Fukugi (Garcinia subelliptica Merr.) homestead woodlands spread through the Ryukyu Islands, the southernmost part of Japan. Homestead woodlands have played a key role in protecting settlements from strong winds, as well as providing timber, green manure, and other services. However, with rapid urbanization and economic and societal change, homestead woodlands in Japan have largely vanished.The primary purpose of this study was to assess residents’ perceptions of homestead woodlands. The secondary purpose was to evaluate residents’ willingness to conserve homestead woodlands using the contingent valuation method (CVM).A survey was conducted in three hamlets with the best-preserved Fukugi homestead woodlands in Okinawa Prefecture. The overwhelming majority of respondents (91%) favored the conservation of homestead woodlands. Residents highly valued the amelioration of the microclimate by homestead woodlands such as serving as windbreaks (85.6%) and cooling the air in summer (60.9%). In contrast, the contribution to biodiversity was only modestly (16.8%) valued. A hierarchical multiple regression model revealed that residents of small islands valued Fukugi trees highly for their function of protection from typhoons. Fukugi homestead woodlands were considered as private goods by the residents as well as by local authorities. Approximately half of the respondents felt that homeowners and/or a local authority such as the hamlet community should be responsible for their conservation. Estimated mean and median WTP values were JPY 1451 (approximately USD14)/household and JPY 1000/household, respectively. The low CV value by the residents and perception of woodlands as private property suggests a relatively low concern for conservation. A BLR model suggested that respondents with better education and higher income were more concerned about conservation. It is suggested that fostering environmental education and awareness will contribute to better conservation of their homestead woodlands. This research result provides information to local policy makers for coastal settlement landscape planning and conservation strategies.

Conifer encroachment study will inform efforts to preserve and restore North Coast oak woodlands

Research news Conifer encroachment study will inform efforts to preserve and restore North Coast oak woodlands O Redwood National Park “It’s one of those things that creeps up on you — not a radical change, but just a clearly shifting trend,” said Dina Moore, a rancher in the Van Duzen River watershed near Eureka. Conifer encroachment on the North Coast mat- ters because it shrinks the already limited acreage of oak woodlands, one of the state’s iconic A 1987 study estimated that 30% landscapes. Oak wood- lands are valuable of the white oak woodlands in one for several reasons, region of Redwood National Park including grazing, hunting and habitat for had been lost to encroachment by oak-associated wildlife Douglas fir since 1850. communities. Several counties are prepar- ing oak woodland conservation plans, and the U.S. Fish and Wildlife Service and the Natural Resources Conservation Service have been providing grants to landowners to pay for tree removal to counter the trend. But these efforts have been hampered by both a Encroaching conifers poor understanding of the extent of conifer encroach- obscure a stand of ment in the region and a lack of research on the best oak in Redwood National Park. ways to address it. A 1987 study estimated that 30% of 12 CALIFORNIA AGRICULTURE • VOLUME 69 , NUMBER 1 Lenya Quinn-Davidson n California’s North Coast, landowners have noticed for decades the steady expansion of conifer stands into grassy oak woodlands. Fire suppression helps to create conditions that allow conifers to sprout and mature among oaks, as in this woodland in Redwood National Park. the white oak woodlands in one region of Redwood National Park had been lost to encroachment by Douglas fir since 1850, but there has been limited re- search since on the encroachment issue. Better information is coming this fall, with the publication of results from a three-year investigation funded by UC Agriculture and Natural Resources (UC ANR) and led by UC Cooperative Extension (UCCE) researchers. The project, “Tools for a changing landscape: Understanding disturbance and vegetation dynam- ics in Northern California oak woodlands,” is using aerial photography and satellite data to generate the first comprehensive map of oak woodland areas in Humboldt and Mendocino counties. Researchers will compare current conditions with historic photos and other data, along with field measurements of tree ages and other characteristics, to evaluate the extent and impact of Douglas fir encroachment. The project has established field sites in multiple locations to study climate, moisture and other condi- tions that may influence encroachment patterns. The information gathered will also help researchers to

Conservation and management of coastal slope woodlands with particular reference to Wales

It now seems likely that the first human colonists to reach this part of the world would have had to negotiate a coastal zone largely comprising a combination of towering sea cliffs, sand dunes, or closed canopy woodland even on some of the steepest slopes. On a few coastal slopes in Wales there are still remnants of these ancient woodlands now considered to be of major conservation interest and representing a coastal habitat that was no doubt much more widespread before human influence. Nevertheless, there are few detailed studies of these woodlands. The purpose of this study, therefore, was to carry out a basic assessment of their ecology and conservation, and to provide both a collation of all existing stands in Wales (Table 1, Fig. 4) and review of all existing ecological surveys. In terms of arboreal species many of the most natural examples are characterised by Quercus petraea (sessile oak) and Corylus avellana (hazel). Some examples, including Gallt y Bwlch in North Wales, are extremely stunted typically growing to a maximum height of about three metres but in places canopy height can be lower than head height. These woodlands are distinctive in other ways and experience environmental conditions that differ from those just a few kilometres inland including less precipitation and more solar radiation. Reflected light from sea water is thought to provide additional solar radiation. Their species composition typically appear very natural with little evidence of management although in some cases there is evidence that coppicing took place many years ago. In Britain there are very few remaining examples of these distinctive coastal woodland and most have not been described in the terms of the United Kingdom’s National Vegetation Classification (Rodwell 1991). However, some appear to have affinities with the so-called Atlantic hazel woodlands of Scotland. After the last Ice Age, hazel and birch were the earliest woody species to become established in the UK dating back some 10,000 years BP. They predate both oak woodlands and the pine forests of Scotland. Hazel became well established in the coastal zones of Wales and Scotland from about 9500 years BP. The evidence provided here suggests a need to further review both the conservation and protection status of these distinctive woodlands.

Development of a spatially-distributed hydroecological model to simulate cottonwood seedling recruitment along rivers

Dam operations have altered flood and flow patterns and prevented successful cottonwood seedling recruitment along many rivers. To guide reservoir flow releases to meet cottonwood recruitment needs, we developed a spatially-distributed, GIS-based model that analyzes the hydrophysical requirements for cottonwood recruitment. These requirements are indicated by five physical parameters: (1) annual peak flow timing relative to the interval of seed dispersal, (2) shear stress, which characterizes disturbance, (3) local stage recession after seedling recruitment, (4) recruitment elevation above base flow stage, and (5) duration of winter flooding, which may contribute to seedling mortality. The model categorizes the potential for cottonwood recruitment in four classes and attributes a suitability value at each individual spatial location. The model accuracy was estimated with an error matrix analysis by comparing simulated and field-observed recruitment success.The overall accuracies of this Spatially-Distributed Cottonwood Recruitment model were 47% for a braided reach and 68% for a meander reach along the Kootenai River in Idaho, USA. Model accuracies increased to 64% and 72%, respectively, when fewer favorability classes were considered. The model predicted areas of similarly favorable recruitment potential for 1997 and 2006, two recent years with successful cottonwood recruitment. This model should provide a useful tool to quantify impacts of human activities and climatic variability on cottonwood recruitment, and to prescribe instream flow regimes for the conservation and restoration of riparian woodlands.

Population variation and natural selection on leaf traits in cork oak throughout its distribution range

A central issue in evolutionary biology is the exploration of functional trait variation among populations and the extent to which this variation has adaptive value. It was recently proposed that specific leaf area (SLA), leaf nitrogen concentration per mass (Nmass) and water use efficiency in cork oak play an important role in adaptation to water availability in the environment. In order to investigate this hypothesis, we explored, first, whether there was population-level variation in cork oak (Quercus suber) for these functional traits throughout its distribution range; if this were the case, it would be consistent with the hypothesis that different rainfall patterns have led to ecotypic differentiation in this species. Second, we studied whether the population-level variation matched short-term selection on these traits under different water availability conditions using two fitness components: survival and growth. We found high population-level differentiation in SLA and Nmass, with populations from dry places exhibiting the lowest values for SLA and Nmass. Likewise, reduced SLA had fitness benefits in terms of growth for plants under dry conditions. However, contrary to our expectations, we did not find any pattern of association between functional traits and survival in nine-year-old saplings despite considerable drought during one year of the study period. These results together with findings from the literature suggest that early stages of development are the most critical period for this species. Most importantly, these findings suggest that cork oak saplings have a considerable potential to cope with dry conditions. This capacity to withstand aridity has important implications for conservation of cork oak woodlands under the ongoing climate change.

Role of Social-Ecological Systems in Forest and Woodland Conservation in Zimbabwean Resettlement Areas

This study investigates the importance of social-ecological systems in the conservation of forest and woodland resources in a planned resettlement area in Zimbabwe. The study uses methodological integration, comprising a questionnaire survey and participatory rural appraisal that were conducted on five randomly selected farms to explore the way resettled communities interact with tree resources and the cultural and traditional practices that they employ to conserve the resources. The study concludes that forest and woodland resource conservation is a function of complex and dynamically linked processes that are not only embedded in biophysical space but also connected to socio-economic and political realms depicting the livelihoods, social needs and culture of members of the resettled communities. This knowledge is important for designing conservation strategies in future resettlement areas.

Woodland Dynamics at the Northern Range Periphery: A Challenge for Protected Area Management in a Changing World

Managers of protected natural areas increasingly are confronted with novel ecological conditions and conflicting objectives to preserve the past while fostering resilience for an uncertain future. This dilemma may be pronounced at range peripheries where rates of change are accelerated and ongoing invasions often are perceived as threats to local ecosystems. We provide an example from City of Rocks National Reserve (CIRO) in southern Idaho, positioned at the northern range periphery of pinyon-juniper (P-J) woodland. Reserve managers are concerned about P-J woodland encroachment into adjacent sagebrush steppe, but the rates and biophysical variability of encroachment are not well documented and management options are not well understood. We quantified the rate and extent of woodland change between 1950 and 2009 based on a random sample of aerial photo interpretation plots distributed across biophysical gradients. Our study revealed that woodland cover remained at approximately 20% of the study area over the 59-year period. In the absence of disturbance, P-J woodlands exhibited the highest rate of increase among vegetation types at 0.37% yr−1. Overall, late-successional P-J stands increased in area by over 100% through the process of densification (infilling). However, wildfires during the period resulted in a net decrease of woody evergreen vegetation, particularly among early and mid-successional P-J stands. Elevated wildfire risk associated with expanding novel annual grasslands and drought is likely to continue to be a fundamental driver of change in CIRO woodlands. Because P-J woodlands contribute to regional biodiversity and may contract at trailing edges with global warming, CIRO may become important to P-J woodland conservation in the future. Our study provides a widely applicable toolset for assessing woodland ecotone dynamics that can help managers reconcile the competing demands to maintain historical fidelity and contribute meaningfully to the U.S. protected area network in a future with novel, no-analog ecosystems.

마을숲 보전 사업에 대한 마을 주민의 참여가능성 -남원시 2개 마을의 경우

마을숲 보전 사업에 대한 마을 주민의 참여가능성 -남원시 2개 마을의 경우

The Social and Environmental Context of Argan Oil Production

In recent decades, argan oil has become one of the most expensive cosmetic oils on world markets. This review outlines the social and environmental context of the argan boom, highlighting its consequences on local livelihoods and conservation. It examines the claims that the argan oil boom has benefited the local population and that it encourages the conservation of argan woodlands.

Effect of proximity of buloke (Allocasuarina luehmannii) trees on buloke early sapling survival in a semiarid environment

Agricultural intensification has led to the dramatic decline of buloke (Allocasuarina luehmannii) and the plant communities it dominates in southern Australia. Conservation of remnant buloke woodlands and revegetation of agricultural land are both required for the persistence and improved ecological function of this threatened community. We examined the effect of proximity of mature buloke trees on early sapling survival, to provide guidelines for revegetation aimed at enhancing degraded remnants. We planted buloke saplings at different distances from the base of remnant mature trees at a site in western Wimmera, Victoria, with and without herbaceous competition. Mature buloke trees altered most soil nutrients (positively), soil water content (negatively) and soil conductivity (positively) at different gradients from the tree base, depending on the factor measured. Mature buloke trees had a strong negative effect on conspecific sapling survival in the first summer after planting in both the presence and absence of an herbaceous understorey, possibly because of the strong effect of trees on soil moisture. Competition from mature buloke was high nearest to the trees (up to 9 m from tree base), but competition from the native understorey also appeared important for saplings in the tree gaps, as evidenced by their improved survival when the understorey was removed. We suggest that to establish buloke saplings in areas where mature trees already occur (i.e. enhancement plantings around isolated paddock trees), planting tubestock outside the canopy of mature buloke is necessary to enhance establishment success.

CLIMATE CHANGE IMPACTS ON WOODLAND SPECIES: IMPLICATIONS FOR THE CONSERVATION OF WOODLAND HABITATS IN IRELAND

Global climate is rapidly changing and, while many studies have investigated the potential impacts of climate change on the distribution of woodland species in the wider European context, few have focused on the impacts of climate change on the distribution of woodland species in Ireland. This study evaluates the potential impact of climate change on the distribution of species characteristic of woodlands and assesses the implications for the conservation of woodlands in Ireland. Only some 2% of the land area of Ireland is covered in semi-natural woodlands, including communities which are conservation priorities such as bog woodland, alluvial forests and Taxus baccata (Yew) woods. We applied an ensemble of species distribution modelling techniques, using atlas data for 104 vascular plant, bryophyte, bird and butterfly species from Ireland, baseline climate data (1961-1990) and projected future climate data (HadCM3 GCM; 2031-2060), at a 10km² resolution. Of the 104 species, 44 modelled well in at least 6 of the 8 models. Under a scenario of unlimited dispersal, almost 50% of species which modelled well were projected to lose climate space, with the largest range contraction projected for the butterfly Aphantopus hyperantus (Ringlet; — 47.7%). The remainder were projected to have increased climate space, with Thecla betulae (Brown hairstreak) and Frángula alnus (Alder buckthorn) having the largest projected increases of 886% and 532% of their current ranges. When a scenario of limited long-range dispersal was considered, all species were projected to lose some of their current range, from a decrease of 52.4% for Carex strigosa (thin-spiked woodsedge) to a decrease of 10.9% for Saxífraga spathularis (St Patrick's cabbage). These results have significant implications for the future of woodlands in Ireland. Conservation management plans for these habitats need greater focus on potential climate change impacts in order to ensure these communities' long-term survival.

Biological fire prevention method: Evaluating the effects of goat grazing on the fire-prone mediterranean scrub

The effect of goat grazing on the shrubby understory of a pine forest in Doñana Natural Park was evaluated using non-destructive measures of vegetation volume over a period of twenty-four months. After establishing grazing exclusion fenced plots 350 adult Payoyas goats were introduced. Vegetation was sampled before the introduction of goats and afterwards twice a year, using the point intercept method and thereby obtaining data of height, frequency, cover and biovolume of species. After two years the total biovolume of the vegetation of the ungrazed area had increased significantly by 32.9%, while at grazed area, vegetation biovolume decreased significantly by 23.1%, leading to a significant decrease in mean height of the species. Although the number of species remained unchanged throughout the study, significant changes in their relative abundance were found in grazed area. The different responses of scrub species to grazing can be used as a tool to control species sensitive to grazing in shrubby forested areas. Significant reduction of total biovolume due to a reduction in vegetation height will help to reduce fire risk, thus contributing to the conservation of Mediterranean woodlands and forests while also fulfilling an important role in the economic and social lives of the rural population of Mediterranean countries.

Patterns of habitat use by female brown long‐eared bats presage negative impacts of woodland conservation management

AbstractReinstating forestry practices, such as coppicing, thinning the understorey and grazing, has become a key element of proposals for improving the conservation value of broadleaved woodlands in Europe. However, the consequences of such woodland management for bats are poorly understood because of a lack of knowledge concerning their habitat requirements. We studied the brown long‐eared bat Plecotus auritus in South East England to determine how their patterns of habitat use could inform conservation management. Radio‐tracking of 38 adult females showed that they foraged primarily in woodland and that each had a foraging area (mean = 4.4 ha) that they returned to on successive nights. Core foraging areas (mean = 2.1 ha) were characterized by more cover and greater species diversity in the understorey layer than more peripheral areas. Hedgerows were also used for foraging in the late summer and autumn. Most conservation activities for this species have focused on protecting roosts in houses and other buildings. While such protection is important for bat conservation, efforts should also be made to protect foraging habitats in woodlands by maintaining cover of native species in the understorey layer and hedgerows that provide connectivity between woodland patches. Common conservation management practices, such as reinstating coppicing or grazing in semi‐natural broadleaved woodlands, could be detrimental for P. auritus and other woodland bats. Their impact on bats should be tested experimentally before they are widely promoted as a woodland conservation strategy.

Conserving threatened Lepidoptera: Towards an effective woodland management policy in landscapes under intense human land-use

Although intensive forestry practices have greatly reduced the biodiversity of native woodland, sympathetic management offers much potential to reverse these negative trends. We tested, using a species-rich group, whether woodland conservation management practices could be of overall benefit, for threatened generalists and specialists alike. Our landscape-scale light-trap experiment compared presence/absence, abundance and species richness of macro-moths at 36 repeatedly sampled sites from six experimental ‘woodland management’ treatments. We recorded 11,670 individuals from 265 species.Our results show that the sheltered, dark, humid, late-successional, high deciduous forest biotope is characterised by high numbers of both individuals and species of moth, and is especially important for some scarce and specialist species of conservation concern.Coppicing and ride widening, which open up dense forest structures, are also valuable woodland conservation tools for macro-moths. Specifically, we show that the mechanism behind the pattern of increased species richness at the woodland-scale involved an increased structural and hence increased micro-climatic and resource diversity for species with an affinity for more open biotopes. This benefits generalist species of conservation concern. Additionally, we show that woodland area is an important factor affecting both moth abundance and species richness in coppiced plots, especially so for nationally declining and severely declining species, suggesting that larger woodlands offer the best opportunities to increase biodiversity through active coppice management.Based on these complementary findings we recommend zoning woodland conservation management practices to take into account the differential value of successional stages for different ecological groups of Lepidoptera.

The fencing paradigm in woodland conservation: consequences for recruitment of a semi‐arid tree

AbstractQuestionHow does long‐term fencing against large domestic herbivores affect regeneration of the dominant tree, Prosopis flexuosa, and hence the structure of semi‐arid woodlands?LocationWoodlands in the Central Monte Desert biome of Argentina, Ñacuñán Man and the Biosphere Reserve area (34° 20′ S, 67° 58′ W) and surrounding cattle‐grazed ranches.MethodsWe compared seedling emergence and survival, the spatial distribution of seedlings and saplings, and the population stage‐based structure of P. flexuosa between paired sites inside and outside the Reserve of Ñacuñán (Argentina), which has been fenced to exclude domestic cattle for ca. 40 yr.ResultsReserve sites had lower tree recruitment and seedling emergence, in spite of having greater seed production and seedling survival. Outside the reserve, survival was higher for seedlings in high‐density clumps than for isolated seedlings. Seedling clumps occurred mostly near adult individuals, where cattle dung was abundant, suggesting an effect of cattle on seed dispersal. The balance between the effects of cattle exclusion on seedling emergence and on seedling survival was reflected in the stage structure of P. flexuosa woodlands, as populations at fenced sites were dominated by adult individuals, whereas those at cattle‐grazed areas presented greater proportions of seedlings and saplings.ConclusionFencing is a common practice used worldwide to exclude conservation areas from human disturbance. For example, it is assumed that disturbed woodlands may recover after fencing, thanks to increased tree recruitment after the exclusion of large herbivores. However, the actual effectiveness of fencing as a tool for forest conservation in overgrazed environments could be controversial because sequential effects of herbivores during the tree regeneration cycle may hamper predictions of the overall balance of the recruitment process. Our results suggest that dispersal by cattle influences the regeneration of P. flexuosa woodlands, and that the positive effects of cattle on seedling emergence compensate for the negative effects on seed production and seedling and sapling survival. Future management of P. flexuosa woodlands in the Central Monte Desert should consider that tree recruitment is closely related to land use, and that cattle exclusion does not necessarily guarantee woodland recovery in the long term.