Native Species Composition Research Articles

Socioeconomics and temperature anomalies: drivers of introduced and native plant species composition and richness in the Canary Islands (1940-2010)

Background: Islands are particularly sensitive to biological invasions. The arrival of humans with their cohort of accompanying species has been cited as one of the primary causes for ecosystem change.
 Question: The introduction of these non-native species has been largely responsible for the tragic disappearance of native island biota and the dismantling of island ecosystems worldwide.
 Methods: Ordination analyses to determined changes in native and exotic species composition along the period analysed.
 Results: Mean temperature on the island of Tenerife has increased by around 0.6 oC in the last 70 years, while minimum temperature has risen by approx. 1.5 oC. Despite overall warming being milder than in the northern hemisphere, owing to the more sensitive biota these changes may have a strong influence on biodiversity. In addition, socioeconomic indicators have also changed significantly over the last 70 years with consequences for nature conservation. In this study, we analyse which parameters are best placed to explain the increase of introduced species, not just in terms of species richness, but also in species composition. We restrict the study to thermophile invasive and introduced species, as they respond more rapidly to climate change.
 Conclusions: We found that socioeconomic aspects of development are important elements that relate closely to the increase in richness and changes in species composition for native as well for introduced species. In the case of invasive species richness, the average minimum temperature is the most closely related variable. However, mean temperature anomalies did not reveal any relationship with these changes.

Increased production and cover in a variable native pasture following intensive grazing management

Native pastures account for approximately half the grazing area of the high-rainfall zone of southern Australia and the appropriate intensity of grazing management to improve pasture production and to sustain native species composition is still debated. This paper describes differences in pasture herbage mass, ground cover and composition for a native pasture managed under three distinct grazing-management intensities (1-, 4- and 20-paddock grazing systems). Grazing-management treatments were implemented for 4 years across a variable landscape and the interaction of grazing management and landscape position (high-, medium- and low-production zones) were examined. Increasing the intensity of grazing management (number of paddocks in the grazing system) resulted in higher standing, green and litter herbage mass and ground cover of pastures, with differences most pronounced in the high-production zone where selective grazing was regulated with grazing management. Landscape position largely influenced pasture composition, with higher pasture production and more productive species (e.g. Microlaena stipoides, Lolium rigidum and legumes) in the high-production zone. Small increases in the DM of native perennial grasses and lower levels of legumes and broad-leaf weeds developed in the 20-paddock system compared with grazing in 1- and 4-paddock systems. Net pasture growth was higher in the 20-paddock than 1-paddock treatment during spring in the last 2 years of the experiment, resulting in 21% (1.6 t DM/ha) more herbage mass accumulated over the year. While productivity and cover were higher under intensive rotational grazing, grazing management had little influence on pasture composition. A stable perennial pasture (>70% perennial grasses) stocking rates that were not degrading and the strong influence of landscape on pasture composition limited management influences. Practically, the results indicated that, at the same stocking rate, increasing the intensity of grazing management can increase the average pasture herbage mass, ground cover and pasture growth by more evenly distributing grazing.

Potential trophic cascades triggered by the barred owl range expansion

ABSTRACTRecently, the barred owl (Strix varia) has expanded its range into the Pacific Northwest of the United States resulting in pronounced effects on the demography and behavior of the northern spotted owl (S. occidentalis caurina). The range expansion has brought together historically allopatric species, creating the potential for significant changes in the avian predator community with possible cascading effects on food‐web dynamics. The adverse effects of the barred owl on the behavior and demography of the northern spotted owl are well‐documented, but little is known about the immediate and long‐term effects changes in the predator community may have on native species composition and ecosystem processes. Based on northern spotted owl and barred owl selection for diet and habitat resources, there is a potential for trophic cascades within the region's predator and prey communities, differing responses by their shared and unique prey species, and possible direct and indirect effects on ecosystem processes. We explored the possible ecological consequences of the barred owl range expansion to wildlife communities of the Pacific Northwest based on the theoretical underpinnings of predator–prey relationships, interspecific competition, intraguild predation, and potential cascading trophic interactions. Negative effects on fitness of northern spotted owls because of interspecific competition with barred owls are strong selection forces that may contribute to the regional extinction of the northern spotted owl. In addition, we posit that shared prey species and those uniquely consumed by barred owls, along with other competing native predators, may experience changes in behavior, abundance, and distribution as a result of increased rates of predation by rapidly expanding populations of barred owls. © 2016 The Wildlife Society.

Large, connected floodplain forests prone to flooding best sustain plant diversity.

Dams, levees, and water withdrawals disrupt hydrologic regimes and associated floodplain forests. Because these forests are also responding to changes in land use, species invasions, and climate change, the relative effects of these factors are hard to disentangle. Most studies of floodplain forests lack historic data, requiring us to rely on recent data or contemporary spatial relationships to these drivers to infer those causes of vegetation dynamics. Here, we use survey data from the 1950s to reconstruct plant community changes across 40 floodplain forests in Wisconsin. We applied two partial least squares regression (PLS) models to evaluate how current site and landscape scale conditions and changes in these conditions since the 1950s influence contemporary patterns of community diversity and composition. Local site variables were among the most important in explaining current composition metrics and their changes, but historic landscape variables and changes in these were also important. Current local diversity (α) was the highest at sites prone to frequent flooding, even at sites in fragmented landscapes. Sites along sinuous rivers in large watershed areas with more contiguous forest had the highest abundance of wetland indicator plants in the re-survey and had the largest increases in α diversity since the 1950s, despite having the highest presence of exotic species then. These same sites have converged in composition, reflecting increases in wetland indicator plants and common native species. These patterns of increasing α diversity coupled with declines in community distinctiveness are uncommon among long-term studies. Increases in wetland plants may indicate that sites have become wetter with hydrologic changes, but these increases may also reflect improved colonization and establishment processes involving a robust regional pool of generalist wetland taxa. Woody and exotic plants typical of upland forests increased at rarely flooded sites in fragmented and urbanizing landscapes, indicating shifts towards a later-successional conditions and a dampened disturbance regime. This has reduced local species diversity and increased regional distinctness at some sites. As hydrologic connections appear to best maintain native species diversity and composition, even in fragmented landscapes, managers should seek to recreate these whenever feasible.

Media analysis in a case study of Šumava National Park: A permanent dispute among interest groups

The proclamation of Šumava National Park as a large-scale protected territory in the early 90′s of the 20th century shortly after the change of the political regime in Czechoslovakia resulted in the onset of discussions among different interest groups. The question of the approach to its management has always been controversial because forest ecosystems were essentially modified due to intensive forest management and in particular, the indigenous vegetation with native species composition has been preserved in insignificant residues only. The discussion between supporters of the “non-intervention regime” and supporters of “forestry approaches” is also reflected in reporting of the media, which addresses the public. The authors use media content analysis and framework based on a CIMO logic to find out whether the media and way of reporting can reflect the dynamism of the acting factors, provide feedback to the policy and decision makers and interests groups, and how the media influence the perception of the forestry sector by the public and, in this connection, the communication of foresters with the public and forest policy enforcement.

Long‐term changes in communities of native coccinellids: population fluctuations and the effect of competition from an invasive non‐native species

Abstract We assessed the changes in abundance and community composition of native species of coccinellids (Coleoptera: Coccinellidae) on deciduous trees that occurred between 1970s and 2010s, in the Czech Republic. As the composition of adult communities varies with host plant and season, coccinellids were sampled in May–June from Acer, Betula and Tilia trees using a standardised sweeping method. This was done before (1976–1986) and after (2011–2014) the arrival of Harmonia axyridis in 2006, with interim samples from a period immediately before it arrived in the Czech Republic (2002–2006). Twenty‐one native species were identified in the total sample of 2674 adults. The abundance of Adalia bipunctata, Coccinella quinquepunctata and Propylea quatuordecimpunctata decreased over the whole period sampled. Declines in abundance of these species were already evident prior to the arrival of H. axyridis. Recent declines in Adalia decempunctata and Calvia quatuordecimguttata followed the arrival H. axyridis. Their abundance was increasing prior to the arrival of H. axyridis, but decreased following its invasion and the latter species might have affected their decline. The abundance of only one species, Calvia decemguttata, increased. Although the abundance of many species decreased and the frequency of some species varied, the diversity of native coccinellid populations (Shannon index) was similar over the 40 years of this study. The changes in species composition can in part be attributed to H. axyridis, the role of other factors (e.g. climate change, habitat degradation) in the long‐term fluctuations in abundance of coccinellids should be considered in future assessments.

Native versus non‐native invasions: similarities and differences in the biodiversity impacts of Pinus contorta in introduced and native ranges

AbstractAimTo determine whether one of the most invasive pine species introduced to the Southern Hemisphere, Pinus contorta, has changed plant species richness, composition, diversity, and litter depth where it has invaded into native open forest, shrub steppe and grassland communities and to assess whether changes were similar in its native and introduced ranges.LocationRío Negro Province, Argentina; Aysén and Araucanía Regions, Chile; Greater Yellowstone Ecosystem, USA.MethodsWe measured changes in plant species richness, species composition and cover, diversity, and litter depth associated with increasing P. contorta tree cover along the invasion front at three sites in the introduced range (Argentina and Chile) and one in the native range (Montana, USA).ResultsPlant species richness and cover generally declined with increasing P. contorta canopy cover, at similar rates in both the introduced and native ranges. However, plant cover was not affected by P. contorta in a forested setting in the introduced range. P. contorta invasion explained more of the decline in species richness in the introduced than native range. Native species composition changed more strongly across the invasion gradient in the introduced than native range. Litter depth increased more rapidly with P. contorta cover in the native than introduced range.Main conclusionsOur results highlight the potential of pines to alter plant communities whether encroaching from forests in the native range or from plantations in the introduced range. Species richness and plant cover declined in both settings; however, individual species abundance and species composition were more impacted in the introduced range than in the native range. We suggest that invading trees have a greater capacity to cause ecological impacts in their introduced than in their native range, particularly where they represent a novel life‐form.

Occurrence of entomopathogenic fungi in atlantic forest soils

Abstract Knowledge of the composition and distribution of native entomopathogenic fungal species are essential to evaluate the potential of biological control in a given ecosystem. In this study, 10 soil samples were collected in two

Patterns of loss of biodiversity associated with invasion by Chrysanthemoides monilifera subsp. monilifera (boneseed) across a large geographic region

SummaryTo investigate the impact of invasion by Chrysanthemoides monilifera ssp. monilifera (boneseed) on plant communities, sites that were invaded and uninvaded were surveyed across Tasmania, South Australia and Victoria, Australia. Above‐ground cover abundance was estimated and samples of the seed bank from invaded and uninvaded sites in each state were collected and germinated in the glasshouse. We compared species richness and composition between invaded and uninvaded sites for both above‐ground and below‐ground samples. Across this broad geographic area, C. monilifera invaded sites had 25% fewer species than uninvaded sites and twice as many exotic species. Most growth forms showed reduced richness in invaded sites. There were no differences in the composition of native species communities between invaded and uninvaded sites in most regions, except South Australia. The composition of the seed bank differed from the above‐ground vegetation, but was similar within each state. Herbs and grasses were most abundant. The species composition of the seed bank was different in invaded sites only in Victoria, suggesting that invasion may negatively influence the capacity of the seed bank to restore vegetation in some areas. However, the underlying mechanisms for the observed patterns were not tested in this study. The capacity of all sites to regenerate effectively from the seed bank was limited and, in order to ensure the conservation of biodiversity into the future, monitoring of species richness at smaller scales, particularly those where management of C. monilifera has occurred, will be needed to ensure management can facilitate the establishment of missing species. This study suggests that C. monilifera impacts a range of functional groups and different species across its distribution and is therefore non‐selective in how it influences changes in communities.

Resilience of invaded riparian landscapes: the potential role of soil-stored seed banks.

We investigated the potential role of soil-stored seed banks in driving vegetation recovery under varying intensities of invasion by the alien tree Eucalyptus camaldulensis along the Berg River in South Africa's Western Cape Province. We asked: How do richness, diversity, and composition of soil-stored seed banks vary with invasion intensity? What is the difference between the seed banks and above-ground vegetation with respect to species richness, diversity, composition, and structure? To what extent do soil-stored seed banks provide reliable sources for restoring native plant communities? Through a seedling-emergence approach, we compared seedling density, richness, and diversity in plots under varying Eucalyptus cover. Seed bank characteristics were also compared with those of the above-ground vegetation. Except in terms of diversity and density, the richness and composition of native species varied significantly among invasion conditions. Despite the paucity of native tree and shrub species in the seed bank, it was more diverse than extant vegetation. Some species occurred exclusively either in the seed bank or in the above-ground vegetation. Although this ecosystem has been degraded by several agents, including Eucalyptus invasion, soil-stored seed banks still offer modest potential for driving regeneration of native plant communities, but secondary invasions need to be managed carefully. Remnant populations of native plants in the above-ground vegetation remaining after E. camaldulensis clearing provide a more promising propagule source for rapid regeneration. Further work is needed to elucidate possible effects of invasion on successional pathways following E. camaldulensis removal and the effects of hydrochory on seed bank dynamics.

Native and exotic plant species respond differently to wildfire and prescribed fire as revealed by meta‐analysis

AbstractQuestionsWildfire is a natural disturbance that shapes vegetation characteristics worldwide, while prescribed fire is increasingly used to modify vegetation composition and structure. Due to invasion of many ecosystems by exotic species, a concern of land managers is whether wildfire and prescribed fire alter plant communities in favour of exotics. We assessed the global literature describing community‐level responses of native and exotic species groups to wildfire and prescribed fire and characterized the geographic and temporal scope of the data to inform research needs.LocationPredominantly the United States of America and Australia.MethodsWe used meta‐analysis to (1) test whether native and exotic species composition (richness or diversity) and performance (cover, density and biomass) differ in response to wildfire and prescribed fire, and (2) assess how the composition and performance of these species groups vary with time elapsed since fire and habitat types.ResultsMost community‐level research on how native and exotic species respond to fire has been conducted in the US and Australia, typically over short time scales, and with a focus on temperate forest and grassland ecosystems. Prescribed fire benefited native composition over short time scales (<1 yr) but, on average, had no effect on native performance, nor on exotic composition or performance. In contrast, wildfire consistently enhanced exotic composition and performance over all time scales, while having no effect on native species composition and significantly reducing native performance. Additionally, responses varied by habitat: native species groups responded positively to prescribed fire in heathlands and to a lesser extent in temperate grasslands, while responding negatively to wildfire in arid shrublands and heathlands, and to a more modest degree in tropical savannas. Exotic species groups responded positively to wildfire in arid shrublands, temperate forests and heathlands.ConclusionsThis quantitative assessment of the literature revealed strong evidence for a positive response of exotics to wildfire, coupled with a striking near‐absence of negative responses. The assessment additionally suggests that while prescribed fire does benefit native composition, on average, it does not appear to greatly facilitate native performance; however site‐specific variation in how communities responded to fire was pronounced, underscoring the importance of local assessments in determining mechanistic drivers and management policy.

Charles A. Geyer Agricultural Botanical Survey of 1838-1839: A Comparison of the Composition of Minnesota Prairies Then and Now

Prairie remnants often serve as targets for restoration despite little knowledge of how they have altered over the past +150 years due to changes in the biotic and abiotic environment including suppression of fire, increased inputs of exogenous nitrogen, extirpation of bison, climate warming associated with the mid-19th century termination of the ‘Little Ice Age’ and 20th century anthropogenic forcing, and invasive introduced species. In this paper I assess the utility of prairie remnants as targets for restoration and management of prairies by examining compositional change of native plants in western Minnesota over the past~170 years. This analysis is made possible by the recent discovery of an unpublished manuscript by Charles A. Geyer as well as the relocation of 100s of herbarium specimens collected by Geyer. Geyer was a botanist with the 1838–1839 expeditions of J.N. Nicollet in western Minnesota and the eastern Dakotas. Comparison of the Geyer data with modern lists taken from the Natural Heritage Information System Releve Database indicates that there has been surprisingly little change in composition of native species. This suggests that, in the aggregate, remnants retain much of their original flora and provide a good target for prairie restoration and management.

Changes in the understorey of mixed coniferous forest plant communities dominated by the American black cherry (Prunus serotina Ehrh.)

In the managed mixed forests of Europe, Prunus serotina increases its territory easily and gradually becomes the predominant component of the shrub layer. However, its impact on species diversity in the invaded stands remains a matter of debate. To assess the relationship between the black cherry and the understorey plant community, 120 relevés of comparable habitat properties but of variable intensity of infestation by P. serotina were made in three forest districts in south-western Poland, where the plant has been present for more than 50years. Habitat features were estimated indirectly for study plots using selected Ellenberg’s species indicator values (nitrogen availability, soil reaction, soil moisture and light conditions). The forest floor of the areas infested with black cherry showed higher proportions of certain plant species with higher requirements for nitrogen supply, soil reaction and moisture content. Furthermore, a significant negative correlation has been found between the abundance of P. serotina and the species richness of the understorey. Also in multiple regression analysis black cherry occurring in the shrub layer has appeared as the variable significantly related to the decrease of species number. Despite those established relationships, feeding species composition data into the redundancy analysis (RDA) procedure showed that the black cherry’s impact on the herb and moss layer explained only a limited proportion of the general variance. Therefore, it is likely that the effect of P. serotina on the native species composition in different forest stands is significantly modified by a set of site-specific environmental variables, interacting with a number of disturbances caused by natural factors and human activity.

The Environment, Not Space, Dominantly Structures the Landscape Patterns of the Richness and Composition of the Tropical Understory Vegetation

The mechanisms driving the spatial patterns of species richness and composition are essential to the understanding of biodiversity. Numerous studies separately identify the contributions of the environment (niche process) and space (neutral process) to the species richness or composition at different scales, but few studies have investigated the contributions of both types of processes in the two types of data at the landscape scale. In this study, we partitioned the spatial variations in all, exotic and native understory plant species richness and composition constrained by environmental variables and space in 134 plots that were spread across 10 counties in Hainan Island in southern China. The 134 plots included 70 rubber (Hevea brasiliensis) plantation plots, 50 eucalyptus (Eucalyptus urophylla) plantation plots, and 14 secondary forest plots. RDA based variation partitioning was run to assess the contribution of environment and space to species richness and composition. The results showed that the environmental variables alone explained a large proportion of the variations in both the species richness and composition of all, native, and exotic species. The RDA results indicated that overstory composition (forest type here) plays a leading role in determining species richness and composition patterns. The alpha and beta diversities of the secondary forest plots were markedly higher than that of the two plantations. In conclusion, niche differentiation processes are the principal mechanisms that shape the alpha and beta diversities of understory plant species in Hainan Island.

Do environmental attributes, disturbances and protection regimes determine the distribution of exotic plant species in Bangladesh forest ecosystem?

Introduction of exotic plant species in the tropics has occurred since the colonial period, and has mostly been for timber production. However, due to uncontrolled distribution and lack of awareness, many of these species became invasive, and have been increasingly reported as a source of threats to native ecosystems. We investigated the exotic species richness, their traits, and biogeographic origin in the Satchari Forest in the north-eastern region of Bangladesh, one of the very few intact terrestrial ecosystems remaining in the country. Boosted Regression Trees and Detrended Correspondence Analysis were performed to determine the contribution of various environmental attributes, protection regimes, and disturbances to explain the distribution of exotic species within Satchari Forest. Among the environmental variables, native species richness, elevation gradient, and soil nutrient parameters were found as good predictors of both exotic species’ presence and richness in the area. In our analysis, number of exotic species showed a unimodal relationship with native species in the reserved forest, where the relationship was negative in the surrounding area. An increase in exotic species with the presence of higher anthropogenic disturbance events, thereby with lower conservation restrictions as well as with lower protection status, was also evident. Our study suggests that enforcing greater protection status and preventing human use can be the best ways to protect native species composition in forest ecosystems with greater conservation values in tropical developing countries.

Eucalyptus invasions in riparian forests: Effects on native vegetation community diversity, stand structure and composition

Effects of alien plant invaders on native ecosystems are widely acknowledged, although the evidence is sometimes speculative, especially in riparian zones. We examined the changes in floristic diversity, stand structure and composition of resident species associated with invasions of Eucalyptus camaldulensis in riparian zones of the Western Cape, South Africa. Using a gradient comparative approach, we compared the richness, diversity (H′) and evenness (J) of resident vegetation in a riparian forest under varying levels of E. camaldulensis percentage canopy cover. We found that species richness, diversity and structural attributes (e.g. height, relative cover and mean basal area) of native species decreased consistently along the invasion gradient. However, evenness did not change significantly with increasing Eucalyptus invasion. Invasion by E. camaldulensis was associated with changes in native plant species composition; although some native species occurred in alien invaded sites, they were more abundant in uninvaded sites. This research offers a baseline from which further experimental work can be conducted to determine the mechanisms responsible for changes attributed to Eucalyptus invasion.

Seed bank responses to wetland restoration: Do restored wetlands resemble reference conditions following sediment removal?

Sedimentation and alterations of natural hydroperiods from watershed cultivation have affected most depressional wetlands in the Great Plains. This can result in altered plant community structure through changes in water availability and depth as well as burial of seed banks. The vegetation and seed banks of 15 wetlands were sampled within the Rainwater Basin Region of Nebraska. Our objectives were to: (1) compare wetland seed bank communities among wetlands with different watershed land uses (reference, restored and impacted by watershed cultivation); (2) determine the available seed bank following sediment removal and establish if wetland zonation occurs in the deeper sediment layer of pre-scraped agricultural wetlands; and (3) determine the similarity between extant vegetation and the seed banks for each wetland land use treatment. There were no significant differences in seed bank species richness and the number and composition of annual, perennial, native, or exotic species among reference, restored, and agricultural playas. Restored wetlands had a greater number of upland species germinate from the surface soil seed bank compared to reference and agricultural playas. Availability of seeds after 30cm of soil was removed (to simulate available seed bank if the wetland was to be restored) in crop land use wetlands was low (2–52 seeds/wetland) making determination of wetland zonation difficult. There was no difference in the similarity between the seed bank and extant vegetation among the three land use treatments. Sediment removal appears to be successful in removing weedy and exotic species from the seed bank; however, the seed bank is not the primary source for playa wetland revegetation. Restored and reference wetlands have similar seed bank community characteristics (i.e., richness) however, each wetland land use treatment was associated with differing plant species and plant guilds.

Does soil seed bank diversity limit post-fire regeneration in small, fragmented, long-unburnt remnants of fire adapted vegetation?

Soil collected from 38 sites on Kangaroo Island in South Australia, containing small remnants of senescent Eucalyptus cneorifolia-dominated mallee, was subject ex situ to both smoke aerosol and heat treatment to simulate burning. Further soil from a subset of 29 of the sites was left untreated as a control. A total of 113 native plant species and 50 introduced species germinated across all sites. Fifty-three of the native plant species that germinated were absent in the above-ground vegetation, including twelve rare or threatened species, and three species previously unrecorded from Kangaroo Island. Fourteen native species and six introduced species germinated in heat plus smoke treated soil but not in untreated soil from the same sites. Non-metric multidimensional scaling ordination indicated differences in native species composition between sites with a long history of sustained livestock grazing (“grazed” sites) and largely ungrazed sites (“ungrazed” sites). On average, significantly more native species germinated from treated soil sampled from “ungrazed” sites than were found in the standing vegetation, while for “grazed” sites this difference was not significant. This indicates the greater potential for post-fire regeneration of native vegetation from the soil seed bank of ungrazed sites than from that of long grazed sites. Both “ungrazed” and “grazed” sites contained weeds in their soil seed banks, including some species which were stimulated by heat plus smoke. This indicated that competition from weeds is potentially a problem when fire is used as a management tool to regenerate senescent understoreys.

Aboveground plant community and seed bank composition along an invasion gradient

Invasive plants can reduce plant diversity and abundance in native grassland communities; however, the effect on the native seed bank is less clear. The objective of this study was to assess the effects of invasion by the exotic grass old world bluestem (OWB; Bothriochloa spp.) on native aboveground plant species composition and seed bank diversity and abundance (i.e., cover, density). In this central Great Plains grassland, OWB invasion had differential effects on native diversity and abundance of both aboveground and seed bank plant communities. Native plant species diversity and cover showed a steep decline as OWB cover increased. No change in native seed density or richness was observed in response to OWB invasion, however, OWB seed density increased with increasing invasion, thus increasing total seed density. Our results indicate that as OWB invasion increases, the native plant community decreases in diversity and abundance. Although, no effect on native seed bank diversity and density was observed in this study, as native seeds are lost through a loss of native species in the plant communities, native seed bank diversity and density is expected to decline.

Effects of elevated nitrogen and exotic plant invasion on soil seed bank composition in Joshua Tree National Park

We investigated the effects of exotic species invasion and 3 years of nitrogen (N) fertilization on the soil seed bank in Joshua Tree National Park, California, USA at four sites along an N deposition gradient. We compared seed bank composition and density in control (no N added) and fertilized (30 kg N ha−1 year−1) plots to determine if the seed bank would reflect aboveground changes due to N fertilization. Soil samples were collected and germinated in a greenhouse over 2 years. In the field, invasive species cover responded positively to N fertilization. However, we did not observe increased seed density of exotic invasive species in fertilized plots. While no significant differences were detected between treatments within sites, exotic invasive grass seeds overwhelmed the seed bank at all sites. Significant differences between sites were found, which may be due to differences in level of invasion, historic N deposition, and soil surface roughness. Sites experiencing low N deposition had the highest seed bank species richness for both control and fertilized treatments. Aboveground plant density did not correlate well with seed bank density, possibly due to the inherent patchiness of soil seed banks and differential ability of species to form seed banks. This seed bank study provided insight into site-specific impacts on native versus invasive species composition of soil seed banks, as well as magnitude of invasion and restoration potential at invaded sites.