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Nitrogen inputs for sustainable crop production for a growing population require the enhancement of biological nitrogen fixation. Efforts to increase biological nitrogen fixation include bioprospecting for more effective nitrogen-fixing bacteria. As bacterial nitrogenases are extremely sensitive to oxygen, most primary isolation methods rely on the use of semisolid agar or broth to limit oxygen exposure. Without physical separation, only the most competitive strains are obtained. The distance between strains provided by plating on solid media in reduced oxygen environments has been found to increase the diversity of culturable potential diazotrophic bacteria. To obtain diverse nitrogen-fixing isolates from natural grasslands, we plated soil suspensions from 27 samples onto solid nitrogen-free agar and incubated them under atmospheric and oxygen-reducing conditions. Putative nitrogen fixers were confirmed by subculturing in liquid nitrogen-free media and PCR amplification of the nifH genes. Streaking of the 432 isolates on nitrogen-rich R2A revealed many cocultures. In most cases, only one community member then grew on NFA, indicating the coexistence of nonfixers in coculture with fixers when growing under nitrogen-limited conditions. To exclude isolates able to scavenge residual nitrogen, such as that from vitamins, we used a stringent nitrogen-free medium containing only 6.42 μmol/L total nitrogen and recultured them in a nitrogen-depleted atmosphere. Surprisingly, PCR amplification of nifH using various primer pairs yielded amplicons from only 17% of the 442 isolates. The majority of the nifH PCR-negative isolates were Bacillus and Streptomyces. It is unclear whether these isolates have highly effective uptake systems or nitrogen reduction systems that are not closely aligned with known nitrogenase families. We advise caution in determining the nitrogen fixation ability of plants from growth on nitrogen-free media, even where the total nitrogen is very limited. [ABSTRACT FROM AUTHOR]

For acoustically signalling animals, the rate of signal degradation is critical for successful communication. Degradation is heavily influenced by habitat characteristics, with sound degrading more rapidly in the presence of environmental obstacles (e.g. vegetation). Land management strategies such as prescribed burns eliminate obstacles and should therefore lead to more efficient sound transmission. Crawfish frogs (Rana areolata) produce long-distance advertisement calls for breeding. Habitats surrounding crawfish frog breeding ponds vary in vegetative density, and prairies surrounding breeding habitat often undergo controlled burns prior to the breeding season. We hypothesised that R. areolata advertisement calls would transmit more efficiently in post-burned prairies compared to other more vegetated habitats. To test this hypothesis, we conducted a sound transmission playback experiment, broadcasting crawfish frog calls in three habitats: forest, prairie, and post-burned prairie. We compared sound degradation measures between habitat types and across distances. We found that crawfish frog calls experienced up to 6.8 dB less excess attenuation in post-burned habitats relative to other habitat types, and that in general, prairie habitats had better sound transmission than forest. These results indicate that land management and habitat structure have consequences for acoustic communication, and may also influence the findings of frog call detection surveys. [ABSTRACT FROM AUTHOR]

Disturbances are drivers of ecosystem function and play important roles in shaping ecological communities. Prescribed fire and grazing disturbances are common management tools in restored and remnant grasslands. The effects of these management actions on plant communities and on vegetation-dwelling invertebrates are generally well studied. However, less is known about their effects on ground-dwelling invertebrates, which can contribute to important ecosystem processes like herbivory, predation, and decomposition. We examined bison grazing and prescribed fire effects on abundance, diversity, and community composition of ground-dwelling invertebrate groups in restored tallgrass prairies using pitfall trap samples. Surprisingly, invertebrate Shannon diversity decreased when bison were present and was unaffected by fire or the fire–bison interaction. Bison, and to a lesser extent fire, also shifted community composition, increasing abundance of ground, rove, and dung beetles, as well as orthopterans and spiders. Prescribed fire generally increased beetles but caused declines in several ecologically diverse invertebrate groups, including harvestmen and true bugs, although these reduced abundances did not lead to differences in overall diversity. Bison presence may amplify the abundances of dominant groups, such as ground and dung beetles and orthopterans, that outcompete other invertebrates and reduce diversity. Implications for insect conservation: Prescribed fire and grazing by bison change ground-dwelling invertebrate community composition, but bison presence did not reduce the abundance of most taxonomic groups. Fire may have short-term negative impacts on some invertebrate groups that promote desirable invertebrate-driven ecosystem processes, but these effects are likely short-lived, and the resulting environmental mosaic under bison and fire management could support biodiversity over the long-term. [ABSTRACT FROM AUTHOR]

Less than 1% of native prairie lands remain in the United States. Located in eastern Washington, the rare habitat called Palouse prairie was largely converted to wheat monocropping. With this conversion came numerous physical, chemical, and biological changes to the soil that may ultimately contribute to reduced wheat yields. Here, we explored how wheat (Tritcum aestivum L.) seedling establishment, plant size, and heading, signifying the developmental transition to flowering, were affected by being planted in prairie soil versus agricultural soils. We then sought to understand whether the observed effects were the result of changes to the soil microbiota due to agricultural intensification. We found that prairie soil enhanced both the probability of wheat seedling survival and heading compared to agricultural soil; however, wheat growth was largely unaffected by soil source. We did not detect effects on wheat developmental transitions or phenotype when inoculated with prairie microbes compared with agricultural microbes, but we did observe general antagonistic effects of microbes on plant size, regardless of soil source. This work indicates that agricultural intensification has affected soils in a way that changes early seedling establishment and the timing of heading for wheat, but these effects may not be caused by microbes, and instead may be caused by soil nutrient conditions. [ABSTRACT FROM AUTHOR]

In her novel Faillir être flingué (2013), contemporary author Céline Minard revisits in her own way the Western, in a context where other writers in France and directors in the United States seize this genre that one might have thought exhausted. After so many films and books, how does it give new perception to the great prairie of the American West, this mythical and founding space? Drawing on the concept of "espace lisse" at Deleuze and Guattari, but also on the recent reflections of ecopoetics in terms of animal tracking, we will try to show that the meadow brings the many characters of this novel to a form of learning in several stages, which the reader also goes through as the pages. [ABSTRACT FROM AUTHOR]

Grassland restoration efforts typically aim to recover lost biodiversity, guided by biologically diverse old‐growth grasslands as a benchmark. In most old‐growth grasslands, forbs greatly outnumber grasses in terms of richness and therefore contribute most to diversity, but globally, restoration practitioners continue to disproportionately focus on increasing perennial grass cover. While such grass‐centric restoration approaches might be appropriate for meeting some restoration goals, an increasing number of studies reveal negative effects of perennial grass cover on forb and total plant diversity in restored grasslands—with cascading consequences for other trophic levels and grassland functionality. To that end, we urge restoration practitioners to recognize the biodiversity costs of grass‐centric approaches and embrace forb‐centric approaches to meet the goal of increasing biodiversity in restorations. Transferring knowledge between well‐studied and understudied grassland systems around the world will facilitate the shared vision of conserving and restoring global grassland biodiversity. [ABSTRACT FROM AUTHOR]

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Global warming, elevated atmospheric CO2 concentrations and increased likeliness of extreme drought and wildfires in many regions will likely favour C4 grass species. To support future management actions, we explored the effect of the encroachment of an invasive perennial C4 grass, Sporobolus cryptandrus on the composition of soil seed banks in dry sand grasslands in Central Europe. In five mass‐locality sites of the species we assessed the composition and vertical segmentation of the soil seed bank in 12 1‐m2 plots along an increasing cover of the invasive species. We found that the seed bank diversity and density decreased with increasing sampling depth; the decrease in density was affected by the increasing S. cryptandrus cover. Neither the diversity nor the seed bank density of other species were affected by increasing S. cryptandrus cover but both were affected by the sampling site. Most of the studied seed bank characteristics were affected by the sampling depth, but none of them were affected by the increasing cover of S. cryptandrus. Increasing cover of S. cryptandrus in the vegetation was associated with an increasing proportion of S. cryptandrus seeds in the seed bank, and we found a low‐density soil seed bank of the species even in plots with no S. cryptandrus cover. Our finding that S. cryptandrus forms a massive soil seed bank, together with the predicted decrease in the precipitation of the summer months and increase in the frequency of droughts in the region, projects further rapid spread of the species. [ABSTRACT FROM AUTHOR]

In many regions, the climate is changing faster during winter than during the other seasons, and a loss of snow cover combined with increased temperature variability can expose overwintering organisms to harmful conditions. Understanding how species respond to these changes during critical developmental times, such as seed germination, helps us assess the ecological implications of winter climate change. To address this concern, we measured the breaking of seed dormancy and cold tolerance of temperate grassland species in the lab and field. In the lab, we ran germination trials testing the tolerance of 17 species to an extreme cold event. In the field, we deployed seeds of two species within a snow manipulation experiment at three locations and measured germination success biweekly from seeds subjected to ambient and reduced snow cover from winter into spring. From lab trials, cold tolerance varied among species, with seed germination decreasing <10%–100% following extreme cold events. Cold tolerance was related to seed traits, specifically less round seeds, seeds that required cold stratification, and seeds that mature later in the season tended to be more impacted by extreme cold temperatures. This variation in seed cold tolerance may contribute to altered community composition with continued winter climate change. In the field, germination increased through late winter, coinciding with the accumulation of days where temperatures were favorable for cold stratification. Through spring, germination success decreased as warm temperatures accumulated. Collectively, species‐specific seed cold tolerances and mortality rates may contribute to compositional changes in grasslands under continued winter climate change. [ABSTRACT FROM AUTHOR]

Juvenile survival is critical to population persistence and evolutionary change. However, the survival of juvenile plants from emergence to reproductive maturity is rarely quantified. This is especially true for long‐lived perennials with extended pre‐reproductive periods. Furthermore, studies rarely have the replication necessary to account for variation among populations and cohorts. We estimated juvenile survival and its relationship to population size, density of conspecifics, distance to the maternal plant, age, year, and cohort for Echinacea angustifolia, a long‐lived herbaceous perennial. In 14 remnant prairie populations over seven sampling years, 2007–2013, we identified 886 seedlings. We then monitored these individuals annually until 2021 (8–15 years). Overall, juvenile mortality was very high; for almost all cohorts fewer than 10% of seedlings survived to age 8 or to year 2021. Only two of the seedlings reached reproductive maturity within the study period. Juvenile survival increased with distance from the maternal plant and varied more among the study years than it did by age or cohort. Juvenile survival did not vary with population size or local density of conspecific neighbors. Our results suggest that low juvenile survival could contribute to projected population declines. [ABSTRACT FROM AUTHOR]

Monitoring snow cover in prairie environments is important for understanding water and energy fluxes, agricultural production, and flooding, but difficult due to shallow snowpack and considerable snow heterogeneity. Cosmic ray neutron sensors (CRNS) are sensitive to snow within a radius of 150–250 m, which allows for continuous estimation of snow water equivalent (SWE) over a large footprint and may better represent area‐averaged snow cover in prairies than conventional SWE instruments, such as snow pillows. A CRNS was installed at Montana State University's Central Agricultural Research Center (CARC; 47.06°, −109.95°) in Moccasin, MT in coordination with NASA's SnowEx 2021 field campaign. This work assesses the feasibility of a CRNS for SWE monitoring in prairies by comparing CRNS SWE estimates to spatially distributed SWE derived from uninhabited aerial vehicle lidar snow depths within the sensor's footprint and manual snow pit measurements. Lidar observations show snow cover was highly spatially variable, with the largest snow accumulation near barriers and the least in barren fields. Additionally, we evaluate our CRNS SWE estimates using Ultra Rapid Neutron Only Simulation (URANOS) Monte Carlo simulations. Comparisons of SWE estimates derived from lidar, CRNS, and URANOS for shallow snowpack at the site yielded root mean square values of about 2 mm (approximately 30% of the mean SWE). These results suggest that the CRNS is effective at integrating over significant spatial variability within its footprint at this site. However, the spatial distribution of snow exerts a strong influence on the CRNS signal and must be considered when interpreting CRNS observations. Plain Language Summary: Snow in prairie environments can be highly variable due to a lack of tree cover and generally low relief, combined with windy conditions. In this study, we determine how accurately a cosmic ray neutron sensor (CRNS) can estimate snow water equivalent (SWE) for an agricultural site in central Montana. We found that our CRNS was sensitive to changes in the amount of water within a radius of 100–200 m from the instrument. For winter 2020–2021, the site experienced high spatial variability in snow depth, ranging from 1.7 m deep snowdrifts along a major windbreak to shallow snow or bare conditions in the agricultural fields that covered most of our 1 km2 study site. We compared CRNS SWE estimates at the site to independent SWE estimates derived from lidar snow depth maps and model simulations, and generally found agreement within the uncertainty of each SWE estimation method. This study supports that CRNS can integrate over the significant spatial variability common in prairie snowpacks, but how the snow varies around a given sensor has a strong influence on CRNS SWE estimates and must be considered when interpreting these types of observations. Key Points: We evaluate cosmic ray neutron sensor (CRNS) snow water equivalent (SWE) estimates using spatially distributed snow observations from lidar at a prairie siteWe use neutron transport model simulations to calibrate a site‐specific weighting function to represent the spatial sensitivity of a CRNSComparison to model‐ and lidar‐derived SWE show that our CRNS effectively estimates SWE for this heterogenous snowpack [ABSTRACT FROM AUTHOR]

Recently exposed reservoir sediments, prone to colonization by invasive species, provide novel settings to test hypotheses related to soil conditions and propagule supply as potential drivers of plant assembly in disturbed ecosystems. We used a dam removal site in southwestern Wisconsin to examine the relationship between the physiochemical properties of dewatered sediments, seeding density, and plant community assembly. The plant communities from five seed densities (1000, 500, 250, 125, and 0 seed m−2) were annually assessed over four years. We hypothesized (1) that the native aboveground biomass and the proportion of native to invasive (non-seeded species) aboveground biomass would increase with the seeding density and (2) that the diversity of seeded native species would increase with a higher seeding density. We found evidence that sowing at least 500 seeds m−2 of prairie species increased their abundance, establishment, and plot diversity compared to non-seeded plants that persisted four years after seeding (p < 0.05). The seeding density treatments led to the assembly of two distinct communities: "native" and "invasive". The "native" community, assembled in plots seeded with at least 500 seeds m−2, had a greater aboveground biomass and diversity (i.e., richness) of seeded plants compared to plots with lower seed densities, and its productivity was positively related to this richness. In the "weedy" community, the diversity of invasive species had no relationship to their aboveground biomass, likely because these species share similar traits (i.e., redundancy) and may have performed similar functions within the plant community. These findings suggest that the seeding density interacted with the disturbed soil resources to increase the diversity and productivity of seeded native species and may serve as a positive feedback mechanism for the establishment of native communities in dewatered sediments. [ABSTRACT FROM AUTHOR]

Abstract Monoculture switchgrass and restored prairie are promising perennial feedstock sources for bioenergy production on the lands unsuitable for conventional agriculture. Such lands often display contrasting topography that influences soil characteristics and interactions between plant growth and soil C gains. This study aimed at elucidating the influences of topography and plant systems on the fate of C originated from switchgrass plants and on its relationships with soil pore characteristics. For that, switchgrass plants were grown in intact soil cores collected from two contrasting topographies, namely steep slopes and topographical depressions, in the fields in multi-year monoculture switchgrass and restored prairie vegetation. The 13C pulse labeling allowed tracing the C of switchgrass origin, which X-ray computed micro-tomography enabled in-detail characterization of soil pore structure. In eroded slopes, the differences between the monoculture switchgrass and prairie in terms of total and microbial biomass C were greater than those in topographical depressions. While new switchgrass increased the CO2 emission in depressions, it did not significantly affect the CO2 emission in slopes. Pores of 18–90 µm Ø facilitated the accumulation of new C in soil, while > 150 µm Ø pores enhanced the mineralization of the new C. These findings suggest that polyculture prairie located in slopes can be particularly beneficial in facilitating soil C accrual and reduce C losses as CO2.

Nitrogen inputs for sustainable crop production for a growing population require the enhancement of biological nitrogen fixation. Efforts to increase biological nitrogen fixation include bioprospecting for more effective nitrogen-fixing bacteria. As bacterial nitrogenases are extremely sensitive to oxygen, most primary isolation methods rely on the use of semisolid agar or broth to limit oxygen exposure. Without physical separation, only the most competitive strains are obtained. The distance between strains provided by plating on solid media in reduced oxygen environments has been found to increase the diversity of culturable potential diazotrophic bacteria. To obtain diverse nitrogen-fixing isolates from natural grasslands, we plated soil suspensions from 27 samples onto solid nitrogen-free agar and incubated them under atmospheric and oxygen-reducing conditions. Putative nitrogen fixers were confirmed by subculturing in liquid nitrogen-free media and PCR amplification of the nifH genes. Streaking of the 432 isolates on nitrogen-rich R2A revealed many cocultures. In most cases, only one community member then grew on NFA, indicating the coexistence of nonfixers in coculture with fixers when growing under nitrogen-limited conditions. To exclude isolates able to scavenge residual nitrogen, such as that from vitamins, we used a stringent nitrogen-free medium containing only 6.42 μmol/L total nitrogen and recultured them in a nitrogen-depleted atmosphere. Surprisingly, PCR amplification of nifH using various primer pairs yielded amplicons from only 17% of the 442 isolates. The majority of the nifH PCR-negative isolates were Bacillus and Streptomyces. It is unclear whether these isolates have highly effective uptake systems or nitrogen reduction systems that are not closely aligned with known nitrogenase families. We advise caution in determining the nitrogen fixation ability of plants from growth on nitrogen-free media, even where the total nitrogen is very limited.

Restoration outcomes are variable, which impairs our ability to plan projects, meet goals, and predict restoration outcomes. Understanding the drivers of this variation is an important research need, especially within urban ecosystems, which support altered abiotic and biotic conditions and face higher rates of loss and degradation than non‐urban areas. Despite the importance of urban areas for restoration, research and practice have largely focused on non‐urban areas. It is unclear if we can extend current knowledge from restoration ecology to urban systems. Here, we surveyed 30 urban prairie restoration plantings across southern Michigan. We collected plant community and site condition data (e.g. soil attributes) and we quantified landscape context as the percentage of urban land surrounding each site. Variation in plant community composition among restorations was related primarily to site‐level factors, such as soil compaction, texture, and water‐holding capacity, rather than landscape context. Non‐prairie species were structured primarily by the local site conditions. There was an increase in non‐prairie richness for sites that experienced warmer local climate conditions, while there was a decrease in non‐prairie richness for sites where soils were less compacted, sandier, and had elevated water‐holding capacity. Prairie species richness responded oppositely. Overall, our study revealed specific factors structuring restoration outcomes in urban contexts and illustrated the importance of local site conditions, not surrounding landscape context, for shaping plant community composition. Restoration practices developed in non‐urban areas should be extended to urban contexts to better understand the impact of local site conditions on plant community development. [ABSTRACT FROM AUTHOR]

Monoculture switchgrass and restored prairie are promising perennial feedstock sources for bioenergy production on the lands unsuitable for conventional agriculture. Such lands often display contrasting topography that influences soil characteristics and interactions between plant growth and soil C gains. This study aimed at elucidating the influences of topography and plant systems on the fate of C originated from switchgrass plants and on its relationships with soil pore characteristics. For that, switchgrass plants were grown in intact soil cores collected from two contrasting topographies, namely steep slopes and topographical depressions, in the fields in multi-year monoculture switchgrass and restored prairie vegetation. The 13C pulse labeling allowed tracing the C of switchgrass origin, which X-ray computed micro-tomography enabled in-detail characterization of soil pore structure. In eroded slopes, the differences between the monoculture switchgrass and prairie in terms of total and microbial biomass C were greater than those in topographical depressions. While new switchgrass increased the CO2 emission in depressions, it did not significantly affect the CO2 emission in slopes. Pores of 18–90 µm Ø facilitated the accumulation of new C in soil, while > 150 µm Ø pores enhanced the mineralization of the new C. These findings suggest that polyculture prairie located in slopes can be particularly beneficial in facilitating soil C accrual and reduce C losses as CO2. [ABSTRACT FROM AUTHOR]

Water returned to the atmosphere as evapotranspiration (ET) is approximately 1.6x global river discharge and has wide‐reaching impacts on groundwater and streamflow. In the U.S. Midwest, widespread land conversion from prairie to pasture to cropland has altered spatiotemporal patterns of ET, yet there is not consensus on the direction of change or the mechanisms controlling changes. We measured ET at three locations within the Long‐Term Agroecosystem Research network along a latitudinal gradient with paired rainfed cropland and prairie sites at each location. At the northern locations, the Upper Mississippi River Basin (UMRB) and Kellogg Biological Station (KBS), the cropland has annual ET that is 84 and 29 mm/year (22% and 5%) higher, respectively, caused primarily by higher ET during springtime when fields are fallow. At the southern location, the Central Mississippi River Basin (CMRB), the prairie has 69 mm/year (11%) higher ET, primarily due to a longer growing season. Differences in climate and that the CMRB prairie is remnant native prairie, while the UMRB and KBS prairies are restored, make it challenging to attribute differences to specific mechanisms. To accomplish this, we examine the energy balance using the Two‐Resistance Method (TRM). Results from the TRM demonstrate that higher surface conductance in croplands is the primary factor leading to higher springtime ET from croplands, relative to prairies. Results from this study provide insight into impacts of warm season grasses on the hydrology of the U.S. Corn Belt by providing a mechanistic understanding of how land use change affects the water budget. Plain Language Summary: Evapotranspiration (ET) consists of evaporation from bare soil and plant leaves. ET is ∼1.6x greater than global river flow and has wide‐reaching impacts on groundwater and streamflow. In the U.S. Midwest, widespread land conversion from prairies to croplands has altered patterns of ET, yet there is no consensus on the direction of this change or the mechanisms controlling changes. In this study we use measurements of ET at three locations within the Long‐Term Agroecosystem Research (LTAR) network that have paired cropland and prairie sites. Surprisingly, we found that in the two northern sites, the croplands had higher ET than the prairies, particularly during springtime when the croplands are fallow. We used mathematical analysis of the energy budget to show that a parameter called the surface conductance controls the differences in ET between the croplands and prairies. During springtime in prairies, the standing, dormant vegetation blocks transfer of water vapor from the land surface, reducing the surface conductance, and limits the ET. Results from this study provide insight into the impact of land conversion from prairies to croplands on the hydrology of the U.S. Corn Belt by providing a mechanistic understanding of how land use change affects the water budget. Key Points: Differences in evapotranspiration between croplands and prairies was quantified by a mechanistic Two Resistance MethodBowen ratio during springtime is higher in prairies than croplandsSurface resistance is the primary factor causing springtime evapotranspiration differences between croplands and prairies [ABSTRACT FROM AUTHOR]

Groundplum milkvetch (Astragalus crassicarpus Nutt. [Fabaceae]) is a native herbaceous forb found in the Great Plains of North America that has high seed dormancy. Previous research found that despite 100% viability, no seeds germinated without treatments to alleviate dormancy (scarification with sandpaper). The goal of this project is to expand on that research and examine the efficacy of additional treatments to alleviate dormancy in groundplum milkvetch seeds. Treatments were designed to mimic fire cues (dry heat, flaming, and smoke) along with a control (no treatment) and scarification. Historically, the Great Plains had frequent fires to which native plants were exposed so it is a reasonable question to ask if fire cues promote germination. We found that the seeds responded to treatment. Final germination percentage was greatest in seeds treated with dry heat or scarification. Smoke treatment did not impact germination differently than the control. Flaming resulted in a faster rate (seeds per day) of germination but longer time to germination compared to the control. Results suggest that groundplum milkvetch seeds did sense and respond to temperature-driven fire cues, but not chemical-driven (smoke), and that dry heat may be the best treatment to promote germination of groundplum milkvetch seeds. [ABSTRACT FROM AUTHOR]

Dispersal by grazing and browsing animals has the potential to structure plant-associated microbes in plant communities. Bison are one of the largest grazing animals in North America and charismatic symbols of the Great Plains. They have an important role in maintaining plant communities in tallgrass prairie and may have played a significant role in microbial dispersal across the Great Plains, along with other grazers and herbivores in general. To determine whether bison saliva could maintain viable fungal propagules, we sampled saliva from bison at Konza Prairie Biological Station. Fifty-nine internal transcribed spacer sequences were recovered from distinct fungal colonies on media selective for Fusarium species and Macrophomina phaseolina, representing at least 26 fungal species. Most sequences were identified as originating from potential plant pathogens, indicating that bison may play a role in spreading plant pathogens throughout the prairie. Given their historic numbers and extensive migration across North America, bison may have had a role in establishing the current structure of the prairie microbiome. [Figure: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Myxospermy, the release of seed mucilage upon hydration, plays multiple roles in seed biology. Here, we explore whether seed mucilage occurs in a suite of temperate grassland species to test if the prevalence of species producing seed mucilage is associated with habitat type or seed characteristics. Seventy plant species found in wet or dry North American temperate grasslands were tested for the presence of seed mucilage through microscopic examination of seeds imbibed with histochemical stain for mucilage. Mucilage production was compared among species with different moisture requirements and seed mass. In this study, 43 of 70 of species tested produced seed mucilage. Seed mucilage did not differ based on habitat type, species moisture requirements, or seed mass. Most seed mucilage was non‐adherent and did not remain stuck to the seed after extrusion. Seed mucilage was a common trait in the surveyed temperate grassland species and was observed in 61% of evaluated species. Surprisingly, seed mucilage was more common in temperate grasslands than in previous ecological surveys from arid/semiarid systems, which found 10%–31% myxospermous species. Given the high prevalence, seed mucilage may influence seedling ecology in temperate grasslands and requires further investigation. [ABSTRACT FROM AUTHOR]

We established a tallgrass prairie restoration experiment on a high school campus in Kansas. This easily accessible natural environment provides students and teachers many options including scientific research, artistic ventures, or simply relaxing in nature. Our restoration project has four main objectives: (1) practicing science; (2) increasing prairie habitat; (3) fostering a sense of place by getting students outside; and (4) facilitating community collaboration. Here, we present an overview of our restoration as a general model that is adaptable for a variety of ecosystems and circumstances. [ABSTRACT FROM AUTHOR]

Prairie moonwort, Botrychium campestre, was discovered in 1990 in the Bonny Prairie Natural Area of eastern Colorado, the species' southernmost occurrence in the Great Plains. In the years following discovery, the population was monitored by recording the number of aboveground plants. From the initial discovery of three plants in 1990, numbers remained low through 1996, and none were observed from 1997 through 2009. An analysis of soil samples collected in 2007 from the site confirmed belowground viable gemmae (vegetative sporophytic propagules produced by the sporophyte stem). Following two years of above-average precipitation in 2008 and 2009, plus artificial watering in those years, 12 aboveground plants were found in 2010. In 2011, another wet year, 63 aboveground plants were recorded. In the following two drought years, the number returned to zero and has remained low in subsequent years. We address the belowground biology of Botrychium and its mycorrhizal symbiont that make possible the persistence of populations in the absence of aboveground plants, as well as correlation with precipitation and implications for detection and conservation of Botrychium populations. [ABSTRACT FROM AUTHOR]

Fire is a vital management tool for maintaining prairie ecosystems. Prescribed burns control invasive species, regulate succession, stimulate plant growth, and are a cheap and effective method for removing excess biomass; however, fire can also inadvertently cause wildlife mortality, placing land managers in a challenging situation. Turtles are especially at risk of mortality from fire because of their low mobility and population sensitivity to reductions in adult survival. We studied ornate box turtles (Terrapene ornata) at 3 sites in Illinois, USA, from 2019–2022 to determine the best predictors of above‐ground activity so land managers can conduct prescribed burns when turtles are underground. We used turtle shell temperature, air temperature, soil temperature, and precipitation data to develop a predictive model of above‐ground activity. The best model for predicting above‐ground activity included an interaction between day of year and current air temperature. Earlier in spring and later in fall, above‐ground activity is more likely at higher air temperatures compared to later in spring and earlier in fall when the same likelihood of above‐ground activity is predicted at lower air temperatures. In spring, we recommend burning in Illinois ornate box turtle habitat before 1 April when air temperature is <10°C and in fall after 1 November when air temperature is <15°C. Above these temperature thresholds, there is a >5% likelihood that turtles in northern populations are above ground. [ABSTRACT FROM AUTHOR]

Abiotic stressors can be major sources of selection, resulting in diverse demographic responses operating via multiple direct and indirect mechanisms. However, unusual weather events are notoriously difficult to study due to their spatial and temporal unpredictability. A severe drought affected the Flint Hills of Kansas in 2018, occurring during the ongoing population‐level studies of three species of declining grassland songbirds: Eastern Meadowlarks (Sturnella magna), Grasshopper Sparrows (Ammodramus savannarum), and Dickcissels (Spiza americana). We compared nest survival, nest initiation date, and potential behavioral drivers of reproductive differences (i.e., nest orientation, investment) between the 2018 drought year and 2–6 years of average‐to‐wet years. Nest initiation in the drought year was concentrated early in the season, suggesting that birds did not renest or attempt second broods. The two species that build domed nests shifted the orientation of nest entrances away from early morning sun and toward the direction of prevailing winds in the drought year. Multiple nest‐level metrics of investment and success were similar in drought and nondrought years. These results suggest that demographic changes during droughts can reflect both direct responses and may also involve biotically mediated trophic consequences. [ABSTRACT FROM AUTHOR]

Phylogenetic and functional diversity are theorised to increase invasion resistance. Experimentally testing whether plant communities higher in these components of diversity are less invasible is an important step for guiding restoration designs.To investigate how phylogenetic and functional diversity of vegetation affect invasion resistance in a restoration setting, we used experimental prairie restoration plots. The experiment crossed three levels of phylogenetic diversity with two levels of functional diversity while species richness was held constant. We allowed invaders to colonise plots; these included native species from neighbouring plots and non‐native invasive species from a surrounding old field. We tested if invader biomass was influenced by phylogenetic and functional diversity, and phylogenetic and hierarchical trait distances between invaders and planted species. We binned each invader into three categories: native species from neighbouring experimental plots (site‐specific invaders), native species not part of the experimental species pool (native invaders) or non‐native species (non‐native invaders).Counter to expectation, both non‐native and native invaders became more abundant in more phylogenetically diverse plots. However, plots with higher abundance of planted Asteraceae, a dominant family of the tallgrass prairie, had lower invader biomass for both native and non‐native invaders.We also found that hierarchical trait differences shaped invasion. The species that became most abundant were non‐native invaders that were taller, and native invaders with low specific leaf area relative to planted species. Site‐specific invaders were not influenced by any plot‐level diversity metrics tested.Synthesis and application: Our results suggest that greater phylogenetic diversity may lower resistance to invasion. This effect may be due to more even but sparser niche packing in high‐diversity plots, associated with greater availability of unsaturated niche space for colonisation. However, trait composition fostered invasion resistance in two ways in our study. First, establishment of native species with strongly dominant traits may confer invasion resistance. Second, species mixes that optimise trait differences between planted vegetation and likely invaders may enhance invasion‐resistance. [ABSTRACT FROM AUTHOR]

Grasslands are among the most impacted ecosystems globally. In the midcontinent of North America, a > 80% loss of grasslands has made their conservation a major priority for resource managers. Grassland ecosystems evolved under periodic disturbances; consequently, grassland management often involves regular actions such as grazing, haying, or burning to maintain ecosystem integrity. The timing of such practices has direct implications on grassland ecology, agricultural economics, and survival and fecundity of grassland nesting birds (hereafter grassland birds). We conducted a meta-analysis on the nesting phenology of grassland birds throughout North America, focusing on nest-survival literature. We constructed a well-fitting model to predict median date of expected nest departure (hereafter fledge date) for grassland birds across the midcontinent. Predictions from our model demonstrate considerable spatial variation in median nesting phenology that is predictable using a spatially explicit spring phenology index. Median fledge dates were 8 or 13 days earlier in years of extreme weather conditions (dry or wet, respectively) than in years of average conditions. Species that generally nest in taller vegetation tended to have later median nest phenologies than those using shorter vegetation. Our results incorporate the most rigorous information available in the literature on nesting phenology of 36 grassland bird species and improve information available to managers about nesting phenology of grassland birds in the midcontinent of North America. Our predictions approximate the day when one-half of the nesting efforts would be complete for a given area within the midcontinent grasslands and can inform management and conservation decisions about the timing of management actions in grassland ecosystems.

American Kestrel (Falco sparverius) populations are generally declining across the species' North American distribution but the population in the Southern High Plains region currently appears to be stable. Historical evidence suggests the region formerly had a low abundance of kestrels, and that their current numbers are due to landscape changes associated with European settlement. We conducted monthly surveys for American Kestrels across 2 yr to estimate seasonal densities and identify land cover associations in the Southern High Plains of Texas. We found an overall estimated density of 0.99 birds/km2 (95% CI = 0.406, 1.582) across the 2-yr period, with seasonal estimated densities highest in autumn and winter (0.92–2.53/ km2), and lowest in spring (0.49–0.67/km2). Whereas other studies have found that temperature influenced detection of wintering kestrels, we found an interaction of drought conditions and snow most strongly influenced the number of kestrels in our study area. Kestrels largely used land cover types in proportion to availability but there was some evidence of seasonal shifts. Generally, they tended to avoid cotton fields and sometimes selected for areas with woodlots, abandoned or occupied houses, and barns, all of which likely provided nesting and roosting opportunities. Our study provides the first contemporary assessment of seasonal abundance and habitat associations of American Kestrels in the Southern High Plains, where their presence and abundance has been unintentionally facilitated by landscape changes following settlement. We provide a baseline for population monitoring and studies assessing response to additional landscape changes (e.g., development of wind energy facilities) and a changing climate. [ABSTRACT FROM AUTHOR]

To our knowledge, the study interconnection between inherent chemical functional group spectral features and nutrient utilisation is still limited. The objective of this study was to test the adequacy of vibrational Fourier transform infrared attenuated total reflectance (ATR‐FTIR) spectroscopy as a fast tool to assess the interactive relationship between the nutritive value of the Prairie cool‐season oat (Avena sativa L.) varieties in dairy cows and inherent chemical functional group spectral features. The chemical functional group spectral features of the Prairie cool‐season oat varieties in western Canada were determined by Fourier transform infrared attenuated total reflectance spectroscopy. The protein‐related spectral parameters of chemical functional groups included peak height and peak area intensity of Amide I, Amid II, protein structural α‐helix and β‐sheet, and their ratios. The rumen degradation kinetics were determined using in situ techniques with four rumen‐canulated lactating dairy cows. The intestinal digestion was evaluated using a three‐step in vitro technique with 12 h preincubation. The experiment was an randomized complete block design. The data were analysed using the mixed‐model procedure of the Statistical Analysis System. The results showed that the interconnection between rumen degradation kinetics, intestinal digestion and true nutrient supply to dairy cows and protein‐related chemical functional group spectral features could be revealed by ATR‐FTIR with univariate and multi‐variate spectral analyses. These findings indicate that ruminant relevant nutritive value of cool‐season oats could be rapidly evaluated and predicted using oat‐specific functional group spectral characteristics which could be obtained by a non‐distractive bioanalytical tool of ATR‐FTIR spectroscopy. [ABSTRACT FROM AUTHOR]

Premise: Fire induces flowering in many plant species worldwide, potentially improving reproductive fitness via greater availability of resources, as evident by flowering effort, and improved pollination outcomes, as evident by seed set. Postfire increases in flowering synchrony, and thus mating opportunities, may improve pollination. However, few studies evaluate fire effects on multiple components of fitness. Consequently, the magnitude and mechanism of fire effects on reproductive fitness remain unclear. Methods: Over multiple years and prescribed burns in a prairie preserve, we counted flowering stems, flowers, fruits, and seeds of three prairie perennials, Echinacea angustifolia, Liatris aspera, and Solidago speciosa. We used aster life‐history models to assess how fire and mating opportunities influenced annual maternal fitness and its components in individual plants. Results: In Echinacea and Liatris, but not in Solidago, fire increased head counts, and both fire and mating opportunities increased maternal fitness. Burned Echinacea and Liatris plants with many flower heads produced many seeds despite low seed set (fertilization rates). In contrast, plants with an average number of flower heads had high seed set and produced many seeds only when mating opportunities were abundant. Conclusions: Fire increased annual reproductive fitness via resource‐ and pollination‐dependent mechanisms in Echinacea and Liatris but did not affect Solidago fitness. The consistent relationship between synchrony and seed set implies that temporal mating opportunities play an important role in pollination. While fire promotes flowering in many plant species, our results reveal that even closely related species exhibit differential responses to fire, which could impact the broader plant community. [ABSTRACT FROM AUTHOR]

Ecosystem restoration is a critical conservation strategy, especially for increasing resilience and resistance to climate change. Current restoration efforts that convert reclaimed agricultural land to native tallgrass prairies typically focus on aboveground communities, but it can take decades to restore soil microbial biodiversity and function using these strategies, if they recover at all. This incomplete restoration can have detrimental impacts on longer-term restoration goals, such as supporting late-successional plant species and facilitating soil carbon sequestration. Soil microorganisms are key components in determining the fate of organic material that enters the soil. They mediate decomposition rates and contribute to plant-microbe-soil interactions, produce microbial biomass, necromass, and metabolic products, and physically protect soil carbon through aggregation. Interactions with plants and controls over soil carbon vary widely depending on the specific microbial taxa present, their physiology, their functional capabilities, and their responses to environmental stressors. Thus, the ability for new restorations, prairie conservation corridors, and prairies planted in marginal lands to act as carbon sinks and help balance greenhouse gas emissions can depend on the success of microbial restoration. Next-generation sequencing approaches can support novel methods for evaluating existing restoration practices and developing microbially focused management strategies. This review summarizes the growing body of literature describing microbially focused tallgrass prairie restoration and considers when and how integrating next-generation sequencing approaches into management efforts can be beneficial. We provide a roadmap for future restoration efforts where microbial ecologists, restoration ecologists, and land managers can work together to meet their goals to promote climate-ready restored ecosystems. [ABSTRACT FROM AUTHOR]

As anthropogenic factors continue to degrade natural areas, habitat management is needed to restore and maintain biodiversity. However, the impacts of different habitat management regimes on ecosystems have largely focused on vegetation analyses, with limited evaluation of downstream effects on wildlife. We compared the effects of grassland management regimes (prescribed burning, cutting/haying, or no active management) on rodent communities and the viruses they hosted. Rodents were trapped in 13 existing grassland sites in Northwest Arkansas, USA during 2020 and 2021. Rodent blood samples were screened for antibodies against three common rodent‐borne virus groups: orthohantaviruses, arenaviruses, and orthopoxviruses. We captured 616 rodents across 5953 trap nights. Burned and unmanaged sites had similarly high abundance and diversity, but burned sites had a higher proportion of grassland species than unmanaged sites; cut sites had the highest proportion of grassland species but the lowest rodent abundance and diversity. A total of 38 rodents were seropositive for one of the three virus groups (34 orthohantavirus, three arenavirus, and one orthopoxvirus). Thirty‐six seropositive individuals were found in burned sites, and two orthohantavirus‐seropositive individuals were found in cut sites. Cotton rats and prairie voles, two grassland species, accounted for 97% of the rodents seropositive for orthohantavirus. Our study indicates that prescribed burns lead to a diverse and abundant community of grassland rodent species compared with other management regimes; as keystone taxa, these results also have important implications for many other species in food webs. Higher prevalence of antibodies against rodent‐borne viruses in burned prairies shows an unexpected consequence likely resulting from robust host population densities supported by the increased habitat quality of these sites. Ultimately, these results provide empirical evidence that can inform grassland restoration and ongoing management strategies. [ABSTRACT FROM AUTHOR]

Purpose: Climate change may alter interactions between plants and their associated soil microbial communities, including microbe-mediated plant-soil feedbacks (PSF). If PSF influence plant performance and abundance in natural communities, climate-induced changes in soil communities might affect local extinction. Here, we examine whether warming-induced shifts in plant-soil interactions are associated with local species loss in tallgrass prairie. Methods: We conducted a traditional two-phase PSF experiment. In phase 1, phylogenetic pairs of locally extinct and extant prairie species were grown under ambient or elevated temperature conditions in the field. In phase 2, soil microbial communities were collected from below those plants and inoculated onto conspecific and heterospecific seedlings grown in the greenhouse. We compared warming effects on plant performance in soil conditioned by locally extinct and extant species as well as net-pairwise PSF between phylogenetic pairs. Results: Locally extinct prairie species were more sensitive to soil biota than extant species, generally performing better when grown in soils cultivated by certain extant species. Meanwhile, extant species were more responsive to warming effects on soil communities than locally extinct species, although the direction and magnitude of temperature effects varied across species. We detected no significant overall effects of warming on net-pairwise PSF. Conclusion: These findings suggest that soil biota might have affected historical plant species losses via negative effects of locally extinct species' soil on their own growth. Warming-induced shifts in soil communities might influence extant prairie species' performance under climate change, indicating a need to consider plant–microbe interactions in future prairie conservation efforts. [ABSTRACT FROM AUTHOR]

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Invasive plant species' success may be a result of allelopathy, or the release of secondary metabolites that are harmful for surrounding plant species. Allelopathy can be mediated through the abiotic environment by chemical sorption or transformation, so the substrate on which interactions occur can lead to differential outcomes in allelopathic potential. One aggressive invader, Pyrus calleryana, has become dominant in many ecosystems throughout Eastern US, and has reduced the abundance of native species where it invades. Thus, our goal was to identify if P. calleryana had allelopathic potential by testing the impact of leaf and flower leachate on gemination of six common grassland species (three grasses and three forbs) in either sterilized sand or field collected soils. Germination of five out of six tested species was reduced by P. calleryana leaf litter, with weaker impacts from flower leachate. This suggests that allelopathy is one mechanism driving the success of P. calleryana and that allelopathic effects may change with plant phenology. For instance, P. calleryana has late leaf senescence in the fall and copious blooming in the spring that may elongate the timeframe that allelopathic inhibition can occur. Further, germination was higher in sand than in soil, suggesting that the context of the abiotic environment can mediate this relationship. In our study, two grass species that could be overabundant in restored grasslands had higher germination rates in soil than sand and one was not altered by P. calleryana suggesting that this relationship could further promote the overabundance of grass species. Taken together, P. calleryana likely inhibits the germination of native species where it invades, but there is context dependency of this relationship with both soil chemistry and seasonality. [ABSTRACT FROM AUTHOR]

Changes in precipitation due to climate change will have consequences for plant and herbivorous insect communities alike. Multiple hypotheses explain how changes in plant diversity and productivity can lead to changes in herbivore community composition. Yet as rainfall patterns change, the bottom‐up effects on the relationships between plant and herbivore communities are less well understood.Using a long‐term rainfall manipulation experiment in a remnant patch of Garry oak (Quercus garryana) savanna, we examined how plant diversity and productivity have responded to variation in soil moisture over 6 years. This highly endangered ecosystem is predicted to experience significantly wetter springs and drier summers by 2080. We also investigated plant‐mediated, indirect effects of manipulated rainfall on herbivore diversity and abundance, drawing on multiple hypotheses describing the relationships between plant and herbivore communities. For example, the more individuals hypothesis predicts that increased plant productivity results in increased herbivore abundance which, in turn, results in increased herbivore diversity.We found that plant productivity was influenced by soil moisture, but the direction and magnitude of the response varied across years, and found no support for plant diversity influencing productivity. We also found that the cover and productivity of grasses increased significantly with increasing precipitation. In addition to a direct negative effect on herbivore diversity, soil moisture had an indirect negative effect on herbivore abundance, via the negative effect of plant productivity on abundance, contradicting the more individuals hypothesis.Synthesis. Our results highlight that not only can drought result in significant reductions in plant productivity in this threatened ecosystem, but that these changes will also result in increases in herbivore abundance. In contrast, where soil moisture is higher, grasses will become more dominant resulting in decreased herbivore abundance. Ultimately, predicting how this system responds to changes in precipitation will depend on the ability to predict whether growing season soil moisture will be consistently drier or wetter in the future, a significant challenge. Going forward, investigating how variation in precipitation due to climate change affects the links between trophic levels, including how herbivores affect plant communities, remains critical for understanding ecosystem processes and stability. [ABSTRACT FROM AUTHOR]

The oriental High Atlas mountains in southeast of Morocco are characterized by small natural wet grasslands called “Almous”, they are suitably well managed by the local population. They are destined to feed cattle and mullets. This trial was implemented in order to assess the effects of nitrogen fertilization on the phytomass production on the Tissila meadow (6.5 Ha) in Imilchil region. The experimental design consisted in dividing the meadow into 3 parcels. One parcel is leaved as control and the other two parcels have received two doses of nitrogen during three periods in the year (D1 =67 kg N/ha (split in three applications October, April and May) plus 46 Kg P2O5/ha (split in two applications April and May); D2 (with applications as D1=134kg N/ha more 46 Kg P2O5/ha; D3 = control). The phytomass production has doubled in Tissila region due to the effect of fertilization basically for dose (D2). The assessment of flora revealed a great specific richness (79 species) and some endemism.

Invasive plant species’ success may be a result of allelopathy, or the release of secondary metabolites that are harmful for surrounding plant species. Allelopathy can be mediated through the abiotic environment by chemical sorption or transformation, so the substrate on which interactions occur can lead to differential outcomes in allelopathic potential. One aggressive invader, Pyrus calleryana, has become dominant in many ecosystems throughout Eastern US, and has reduced the abundance of native species where it invades. Thus, our goal was to identify if P. calleryana had allelopathic potential by testing the impact of leaf and flower leachate on gemination of six common grassland species (three grasses and three forbs) in either sterilized sand or field collected soils. Germination of five out of six tested species was reduced by P. calleryana leaf litter, with weaker impacts from flower leachate. This suggests that allelopathy is one mechanism driving the success of P. calleryana and that allelopathic effects may change with plant phenology. For instance, P. calleryana has late leaf senescence in the fall and copious blooming in the spring that may elongate the timeframe that allelopathic inhibition can occur. Further, germination was higher in sand than in soil, suggesting that the context of the abiotic environment can mediate this relationship. In our study, two grass species that could be overabundant in restored grasslands had higher germination rates in soil than sand and one was not altered by P. calleryana suggesting that this relationship could further promote the overabundance of grass species. Taken together, P. calleryana likely inhibits the germination of native species where it invades, but there is context dependency of this relationship with both soil chemistry and seasonality.

Mounting evidence suggests that plant–soil feedbacks (PSF) may determine plant community structure. However, we still have a poor understanding of how predictions from short‐term PSF experiments compare with outcomes of long‐term field experiments involving competing plants. We conducted a reciprocal greenhouse experiment to examine how the growth of prairie grass species depended on the soil communities cultured by conspecific or heterospecific plant species in the field. The source soil came from monocultures in a long‐term competition experiment (LTCE; Cedar Creek Ecosystem Science Reserve, MN, USA). Within the LTCE, six species of perennial prairie grasses were grown in monocultures or in eight pairwise competition plots for 12 years under conditions of low or high soil nitrogen availability. In six cases, one species clearly excluded the other; in two cases, the pair appeared to coexist. In year 15, we gathered soil from all 12 soil types (monocultures of six species by two nitrogen levels) and grew seedlings of all six species in each soil type for 7 weeks. Using biomass estimates from this greenhouse experiment, we predicted coexistence or competitive exclusion using pairwise PSFs, as derived by Bever and colleagues, and compared model predictions to observed outcomes within the LTCE. Pairwise PSFs among the species pairs ranged from negative, which is predicted to promote coexistence, to positive, which is predicted to promote competitive exclusion. However, these short‐term PSF predictions bore no systematic resemblance to the actual outcomes of competition observed in the LTCE. Other forces may have more strongly influenced the competitive interactions or critical assumptions that underlie the PSF predictions may not have been met. Importantly, the pairwise PSF score derived by Bever et al. is only valid when the two species exhibit an internal equilibrium, corresponding to the Lotka–Volterra competition outcomes of stable coexistence and founder control. Predicting the other two scenarios, competitive exclusion by either species irrespective of initial conditions, requires measuring biomass in uncultured soil, which is methodologically challenging. Subject to several caveats that we discuss, our results call into question whether long‐term competitive outcomes in the field can be predicted from the results of short‐term PSF experiments. [ABSTRACT FROM AUTHOR]

The development and assessment of Piedmont upland grassland restoration efforts is hampered in part by continued challenges in identifying immature individuals of three associated pines, Pinus echinata, P. taeda, and P. virginiana, the penultimate of which is thought alien to the system. To help fill this gap, we studied three quantitative and 25 qualitative characters in 174, 2- to 5-year-old saplings in managed stands in Durham County (North Carolina) and 169 herbarium specimens of mature individuals from 94 Piedmont counties from Georgia to Virginia. Although mean short-shoot needle and fascicle sheath lengths differed significantly between lifestage classes of the three species (F8,335=185, p<0.0001 and F8,335=173.5, p<0.0001, respectively), there was substantial range overlap, likely contributing to diagnostic confusion in the field when existing keys are applied. For example, needle length ranges of all lifestage classes of all species overlapped with those of mature P. echinata and 2-year-old P. virginiana. In addition, at the apex of the previous season's growth, 2-year-old saplings of P. echinata and P. virginiana exhibited needles either predominantly or in higher percentages of threes, than the contrasting described preponderance of pairs for mature individuals. Of the 25 qualitative characters evaluated, we found (1) absence of decurrency glaucescence distinguishes 2- to 5-year-old saplings of P. taeda from P. echinata and P. virginiana, and (2) absence of stomatal plugs distinguishes P. virginiana from the others. A diagnostic key to saplings is provided. [ABSTRACT FROM AUTHOR]

An understanding of interactions between anthropogenic stressors and intrinsic population drivers is needed to fully understand wildlife population declines. Density dependence is a key aspect of population regulation for many species, especially for species that have high reproductive potential, such as amphibians. However, patterns of density dependence have been characterized for only a few species and little work has evaluated how density‐dependent interactions may be altered by anthropogenic stressors. We combined the results of a mesocosm experiment with demographic population modeling to investigate how the conversion of native prairie to agricultural grasslands dominated by Tall Fescue grass (Lolium arundinacea) affected larval density dependence and adult population size of an imperiled amphibian, Lithobates areolatus (Crawfish Frog). Overall, density dependence was overcompensatory, suggesting that L. areolatus exhibits scramble competition as larvae. Both vegetation treatments had low survival at high densities, but more individuals survived to metamorphosis at moderate densities in Fescue treatments compared to Prairie treatments. We evaluated the implications of our experimental results using a stochastic density‐dependent matrix population model to project long‐term population dynamics. Simulated populations breeding in Fescue‐dominated wetlands had a more variable population size and up to 400% higher probability of quasi‐extinction within 200 years, compared to populations breeding in ponds with prairie vegetation. Without varying density in experimental treatments and using mathematical models to project emergent population dynamics, our mesocosm experiment results would have suggested a slightly positive effect of Fescue grass on amphibian development and survival. Vegetation changes surrounding breeding wetlands might play an important role in the decline of amphibian populations persisting in low‐intensity agricultural areas. [ABSTRACT FROM AUTHOR]

The subject of the article is Henryk Sienkiewicz's three-year- long stay in the United States (1876–1878), as well as its result—"Letters from a Trip to America" and short stories inspired by this trip (with particular emphasis on "Sachem"). The article concentrates on the way the author presents both geographic and social aspects of America as well as ideological and artistic interpretation. Sienkiewicz in his writings presents the nature of American democracy, ideas of freedom and equality at the same time noticing unjust treatment and extermination of the Indigenous Americans. In his "American" works Sienkiewicz hones his writing skills, in particular abilities of description. This article also shows how the stay in America influenced Sienkiewicz's worldview and his later works, in particular his historical novels. [ABSTRACT FROM AUTHOR]

Dichanthelium caerulescens is documented for the first time in Louisiana, as the result of floristic fieldwork performed in 2019 through 2021. Louisiana records extend the range of D. caerulescens westward by approximately 265 mi (426.5 km) into the Western Gulf Coastal Plain ecoregion. These findings also identify a new habitat, coastal prairie, utilized by D. caerulescens. [ABSTRACT FROM AUTHOR]

Summary: Shifts in flowering phenology are important indicators of climate change. However, the role of precipitation in driving phenology is far less understood compared with other environmental cues, such as temperature.We use a precipitation reduction gradient to test the direction and magnitude of effects on reproductive phenology and reproduction across 11 plant species in a temperate grassland, a moisture‐limited ecosystem. Our experiment was conducted in a single, relatively wet year. We examine the effects of precipitation for species, functional types, and the community.Our results provide evidence that reduced precipitation shifts phenology, alters flower and fruit production, and that the magnitude and direction of the responses depend on functional type and species. For example, early‐blooming species shift toward earlier flowering, whereas later‐blooming species shift toward later flowering. Because of opposing species‐level shifts, there is no overall shift in community‐level phenology.This study provides experimental evidence that changes in rainfall can drive phenological shifts. Our results additionally highlight the importance of understanding how plant functional types govern responses to changing climate conditions, which is relevant for forecasting phenology and community‐level changes. Specifically, the implications of divergent phenological shifts between early‑ and late‐flowering species include resource scarcity for pollinators and seed dispersers and new temporal windows for invasion. [ABSTRACT FROM AUTHOR]