Native Prairie Research Articles

Conservation planning for pollinators in the U.S. Great Plains: considerations of context, treatments, and scale

AbstractPopulations of many species of grassland‐associated butterflies, moths, and bumblebees in the Great Plains of North America are experiencing steep declines due to habitat loss and degradation—primarily conversion of grasslands to row‐crop agriculture and invasion of woody plants and exotic cool‐season grasses—and insecticide use. These declines are exacerbated by the generally limited dispersal ability of insects, which make local populations susceptible to extirpation following habitat fragmentation. Interest in pollinator conservation has grown substantially in recent years, but information to guide pollinator conservation across the region is limited. We used pollinator biology along with principles of landscape ecology and metapopulation dynamics to develop a simple decision matrix based on patch size and inter‐patch distances to guide landscape‐scale grassland conservation efforts in the U.S. northern Great Plains. When applied to spatial land cover data depicting potential pollinator habitat, the matrix uses landscape characteristics to guide placement of conservation treatments to help ensure persistence of target pollinator populations. Patch size and connectivity thresholds can be set to match characteristics of target species, but in all cases, local management will be necessary to ensure that fine‐grained features such as nectar sources and host plants are present. Applying the matrix to habitat layers for a nine‐state analysis region showed substantial geographic variation in conservation needs, opportunities, and potential treatments. We also demonstrate that non‐native planted cover such as alfalfa and certain grasslands enrolled in the Conservation Reserve Program can substantially enhance landscape structure by increasing grassland patch size and core area while decreasing distance between patches. Pollinators dependent on native prairie will also benefit from planted cover that provides nectar sources and serves as a buffer from pesticides associated with croplands. Consistent with the principles of strategic habitat conservation, targeted monitoring and research will be necessary to validate and adapt the model to meet local conditions.

Estimating Perceptual Range of Female Monarch Butterflies (Danaus plexippus) to Potted Vegetative Common Milkweed (Asclepias syriaca) and Blooming Nectar Resources.

Habitat loss in the summer breeding range contributes to eastern North American monarch (Lepidoptera: Nymphalidae) population decline. Habitat restoration efforts include increasing native prairie plants for adult forage and milkweed (Asclepias spp.) for oviposition and larval development. As the monarch is a vagile species, habitat establishment at a grain that matches the monarch perceptual range will facilitate efficient movement, decrease fitness costs of dispersal, and increase oviposition. We released 188 experimental monarch females 5, 25, 50, and 75 m downwind from potted milkweed and blooming forbs in 4-32 ha sod fields. Perceptual range was estimated from monarchs that flew towards and landed on the milkweed and forbs. Flight patterns of 49 non-experimental monarchs that landed on the resources were also observed. In our experimental, resource-devoid setting, wind-facilitated movement occurred most frequently. Monarchs performed direct displacement as evidenced by shallow turn angles and similarity of Euclidian and total distances traveled. We hypothesize similar monarch flight behavior when traveling over other resource-devoid areas, such as crop fields. Although the majority of experimental monarchs flew downwind, eight experimental and 49 non-experimental monarchs were observed flying upwind toward, and landing on, the potted resources from distances ranging from 3 to 125 m (mean = 30.98 m, median = 25 m, mode = 25 m). A conservative estimate of the perceptual range is 125 m, as longer distances cannot be precluded; however, the majority of observations were ≤50 m. Our findings suggest establishing habitat patches ~ 50 m apart would create functional connectivity across fragmented agricultural landscapes.

Vegetation richness, diversity, and structure influence arthropod communities of native and restored northern mixed‐prairies

We studied the effects of vegetation species richness, diversity, and structure on grassland arthropod communities of 23 sites in northeastern South Dakota and southeastern North Dakota. Sites were selected to represent a vegetation species diversity gradient, and three vegetation cover types, including native unseeded grassland, low‐diversity seeding known as dense nesting cover (DNC) for waterfowl, and high‐diversity seed mix. During July of 2016, pan traps and sweep nets were used to survey the grassland arthropod community. A total of 25,521 arthropods representing 107 taxonomic families were collected. Richness, diversity, and biomass of arthropods did not differ among cover types. Vegetation richness and diversity, cover type, percent live vegetation and native cover, and litter depth were important predictors of arthropod community measures, and multivariate analysis of the arthropod community indicated significant differences between native and DNC study sites; explained by differences in vegetation richness, percent forb cover, and litter depth. Results of our study suggest that species richness of grassland restoration seeding mixes likely impacts arthropod richness and diversity, and DNC does not produce arthropod communities similar to native prairie. Additionally, because vegetation structural variables were important determinants of arthropod community measures, grassland management practices will influence the resulting arthropod community and influence the success of grassland restoration using high‐diversity seed mixes. Results of our study promote the potential for successful restoration outcomes using high‐diversity seed mixes, and indicate that low‐diversity, non‐native seed mixes, such as DNC, do not fully restore native grassland arthropod communities.

Maize yields from manure and mineral fertilizers in the 100‐year‐old Knorr–Holden Plot

AbstractIt takes years, if not decades, before measurable changes in crop productivity and soil properties due to management practices can be detected. The objective of this experiment was to evaluate the effects of long‐term cattle manure and inorganic fertilizer applications on irrigated continuous maize grain yield, yield stability and reliability, nitrogen use efficiency (NUE), and soil properties. The experiment was conducted at the Knorr–Holden Plot in Scottsbluff, NE, from 1912–2012. Maize received no fertilizer in the first 30 yr of the experiment, and yields declined as nutrient supply from the native prairie was used. In 1942–1952, there were two cattle manure rates (0 and 27 kg ha–1 yr–1), and yield significantly increased in the manure treatment. In 1953, second replication and six inorganic N treatments were added effectively, making the study a randomized complete block with manure as the main and inorganic N as subplot factor with two replications. Linear regression of yield against years in manured plots had similar slopes across N rates. There was a gradual increase in slope with increasing N rates in non‐manured plots. Yield response to inorganic N rates in the non‐manured plot had a significantly greater slope but lower intercepts than the manured plot. Manure provided greater yield stability and reliability and significantly increased soil organic matter, nitrate‐N, and P accumulation in soil. Optimized manure and inorganic fertilizer N management are necessary to provide a stable and reliable yield and help establish an economically and environmentally sustainable maize production system.

Effects of bale feeder design on hay waste, intake, and apparent diet digestibility in gestating beef cows.

Two experiments were conducted to determine the effects of feeder design on hay intake, apparent diet digestibility, and hay waste in gestating beef cows. Native tallgrass prairie hay and a protein supplement was fed throughout both experiments. In Exp. 1, 56 crossbred cows were used in a Latin square arrangement. Feeder design treatments included a conventional open bottom steel ring (OBSR), an open bottom polyethylene pipe ring (POLY); a sheeted bottom steel ring (RING), and a sheeted bottom steel ring with a basket (BASK). Cows were weighed and allotted based on BW to one of four previously grazed 2.0 ha paddocks equipped with a concrete feeding pad. Fourteen cows were assigned to each paddock and three round bales were fed consecutively within each treatment period. The cows acclimated to the feeders while the first bale was being consumed. Subsequently, hay waste data were collected while the second and third bale within each period were being consumed. Waste was measured for each bale at 24, 48, 72, and 96 h after each bale was introduced into the pen. Hay waste was significantly affected by hay feeder design with 19.7, 21.1, 12.4, and 5.5% of original bale weight wasted for OBSR, POLY, RING, and BASK, respectively (P < 0.01). There was a feeder design × day interaction (P < 0.01) with greater waste when the bale was first introduced into the pen in OBSR, POLY, and RING feeders and gradually declining thereafter, while waste from the BASK feeder was consistently low. There was a tendency (P = 0.06) for cows eating from OBSR feeders to consume less hay than cows eating from RING feeders. Feeder design did not influence apparent diet digestibility (P = 0.46). In Exp. 2, 64 crossbred cows (body weight = 590 ± 59 kg) were used to determine waste, forage intake, and apparent diet digestibility when hay was fed from a sheeted bottom steel ring (RING) or a RING feeder with a cone insert (CONE). More hay was wasted when cows were fed from RING feeders compared to CONE feeders (11.9% vs. 4.8%, P < 0.01). Feeder design had no effect on DMI or apparent digestibility (P > 0.45). Hay savings from adopting a more conservative feeder design can have a dramatic influence on hay utilization by beef cows and thus on cost of production.

Temporal Changes of Virus-Like Particle Abundance and Metagenomic Comparison of Viral Communities in Cropland and Prairie Soils.

ABSTRACTDuring the last several decades, viruses have been increasingly recognized for their abundance, ubiquity, and important roles in different ecosystems. Despite known contributions to aquatic systems, few studies examine viral abundance and community structure over time in terrestrial ecosystems. The effects of land conversion and land management on soil microbes have been previously investigated, but their effects on virus population are not well studied. This study examined annual dynamics of viral abundance in soils from a native tallgrass prairie and two croplands, conventional till winter wheat and no-till canola, in Oklahoma. Virus-like particle (VLP) abundance varied across sites, and showed clear seasonal shifts. VLP abundance significantly correlated with environmental variables that were generally reflective of land use, including air temperature, soil nitrogen, and plant canopy coverage. Structural equation modeling supported the effects of land use on soil communities by emphasizing interactions between management, environmental factors, and viral and bacterial abundance. Between the viral metagenomes from the prairie and tilled wheat field, 1,231 unique viral operational taxonomic units (vOTUs) were identified, and only five were shared that were rare in the contrasting field. Only 13% of the vOTUs had similarity to previously identified viruses in the RefSeq database, with only 7% having known taxonomic classification. Together, our findings indicated land use and tillage practices influence virus abundance and community structure. Analyses of viromes over time and space are vital to viral ecology in providing insight on viral communities and key information on interactions between viruses, their microbial hosts, and the environment.IMPORTANCE Conversion of land alters the physiochemical and biological environments by not only changing the aboveground community, but also modifying the soil environment for viruses and microbes. Soil microbial communities are critical to nutrient cycling, carbon mineralization, and soil quality; and viruses are known for influencing microbial abundance, community structure, and evolution. Therefore, viruses are considered an important part of soil functions in terrestrial ecosystems. In aquatic environments, virus abundance generally exceeds bacterial counts by an order of magnitude, and they are thought to be one of the greatest genetic reservoirs on the planet. However, data are extremely limited on viruses in soils, and even less is known about their responses to the disturbances associated with land use and management. The study provides important insights into the temporal dynamics of viral abundance and the structure of viral communities in response to the common practice of turning native habitats into arable soils.

MetFish: a Metabolomics Pipeline for Studying Microbial Communities in Chemically Extreme Environments.

ABSTRACTMetabolites have essential roles in microbial communities, including as mediators of nutrient and energy exchange, cell-to-cell communication, and antibiosis. However, detecting and quantifying metabolites and other chemicals in samples having extremes in salt or mineral content using liquid chromatography-mass spectrometry (LC-MS)-based methods remains a significant challenge. Here, we report a facile method based on in situ chemical derivatization followed by extraction for analysis of metabolites and other chemicals in hypersaline samples, enabling for the first time direct LC-MS-based exometabolomics analysis in sample matrices containing up to 2 M total dissolved salts. The method, MetFish, is applicable to molecules containing amine, carboxylic acid, carbonyl, or hydroxyl functional groups, and it can be integrated into either targeted or untargeted analysis pipelines. In targeted analyses, MetFish provided limits of quantification as low as 1 nM, broad linear dynamic ranges (up to 5 to 6 orders of magnitude) with excellent linearity, and low median interday reproducibility (e.g., 2.6%). MetFish was successfully applied in targeted and untargeted exometabolomics analyses of microbial consortia, quantifying amino acid dynamics in the exometabolome during community succession; in situ in a native prairie soil, whose exometabolome was isolated using a hypersaline extraction; and in input and produced fluids from a hydraulically fractured well, identifying dramatic changes in the exometabolome over time in the well.IMPORTANCE The identification and accurate quantification of metabolites using electrospray ionization-mass spectrometry (ESI-MS) in hypersaline samples is a challenge due to matrix effects. Clean-up and desalting strategies that typically work well for samples with lower salt concentrations are often ineffective in hypersaline samples. To address this gap, we developed and demonstrated a simple yet sensitive and accurate method—MetFish—using chemical derivatization to enable mass spectrometry-based metabolomics in a variety of hypersaline samples from varied ecosystems and containing up to 2 M dissolved salts.

Metagenomic analysis reveals the shared and distinct features of the soil resistome across tundra, temperate prairie, and tropical ecosystems

BackgroundSoil is an important reservoir of antibiotic resistance genes (ARGs), but their potential risk in different ecosystems as well as response to anthropogenic land use change is unknown. We used a metagenomic approach and datasets with well-characterized metadata to investigate ARG types and amounts in soil DNA of three native ecosystems: Alaskan tundra, US Midwestern prairie, and Amazon rainforest, as well as the effect of conversion of the latter two to agriculture and pasture, respectively.ResultsHigh diversity (242 ARG subtypes) and abundance (0.184–0.242 ARG copies per 16S rRNA gene copy) were observed irrespective of ecosystem, with multidrug resistance and efflux pump the dominant class and mechanism. Ten regulatory genes were identified and they accounted for 13–35% of resistome abundances in soils, among them arlR, cpxR, ompR, vanR, and vanS were dominant and observed in all studied soils. We identified 55 non-regulatory ARGs shared by all 26 soil metagenomes of the three ecosystems, which accounted for more than 81% of non-regulatory resistome abundance. Proteobacteria, Firmicutes, and Actinobacteria were primary ARG hosts, 7 of 10 most abundant ARGs were found in all of them. No significant differences in both ARG diversity and abundance were observed between native prairie soil and adjacent long-term cultivated agriculture soil. We chose 12 clinically important ARGs to evaluate at the sequence level and found them to be distinct from those in human pathogens, and when assembled they were even more dissimilar. Significant correlation was found between bacterial community structure and resistome profile, suggesting that variance in resistome profile was mainly driven by the bacterial community composition.ConclusionsOur results identify candidate background ARGs (shared in all 26 soils), classify ARG hosts, quantify resistance classes, and provide quantitative and sequence information suggestive of very low risk but also revealing resistance gene variants that might emerge in the future.Aify4ac4FW_3-HKjdJXvGWVideo abstract

WINTERING HABITAT ASSOCIATIONS OF A DECLINING GRASSLAND BIRD, THE SPRAGUE'S PIPIT (ANTHUS SPRAGUEII)

The Sprague's pipit (Anthus spragueii) is a passerine of North American prairies, breeding in the northern United States and southern Canada, and overwintering in the grasslands and deserts of the southern United States and northern Mexico. In recent decades, pipit populations have declined in both breeding and wintering ranges because of degradation and loss of native prairie. Previous research on this species has focused primarily on its breeding habitat and provided limited information on its wintering habitat. To help fill in these data gaps, we assessed wintering density along the Texas Gulf Coast Plain, as well as characteristics of the associated habitat. We used a distance-based line-transect sampling technique to estimate pipit densities during the winters of 2013–2014 and 2014–2015 at seven conservation sites and found Sprague's pipits at all sites. The highest number of detections and the highest density estimates were at the Attwater Prairie Chicken National Wildlife Refuge. Habitat associated with pipits included open grasslands with mixed forbs and low vertical cover. Although wildlife biologists consider pipits to be native grassland specialists in their breeding range, our analyses did not identify proportion of native grasses as an important variable. Instead, the physical structure of the vegetation (short and sparse grass cover) was most important to pipit presence. Our results suggest that habitat management to benefit wintering populations of this species should focus on vegetation structure, though native grassland cover might be important at a larger scale.

Ambient urban N deposition drives increased biomass and total plant N in two native prairie grass species in the U.S. Southern Great Plains.

Remnants of native tallgrass prairie experience elevated atmospheric nitrogen (N) deposition in urban areas, with potential effects on species traits that are important for N cycling and species composition. We quantified bulk (primarily wet) inorganic N (NH4+-N + NO3--N) deposition at six sites along an urban development gradient (6–64% urban) in the Dallas-Fort Worth metropolitan area from April 2014 to October 2015. In addition, we conducted a phytometer experiment with two common native prairie bunchgrass species––one well studied (Schizachyrium scoparium) and one little studied (Nasella leucotricha)––to investigate ambient N deposition effects on plant biomass and tissue quality. Bulk inorganic N deposition ranged from 6.1–9.9 kg ha-1 yr-1, peaked in spring, and did not vary consistently with proportion of urban land within 10 km of the sites. Total (wet + dry) inorganic N deposition estimated using bulk deposition measured in this study and modeled dry deposition was 12.9–18.2 kg ha-1 yr-1. Although the two plant species studied differ in photosynthetic pathway, biomass, and tissue N, they exhibited a maximum 2-3-fold and 2-4-fold increase in total biomass and total plant N, respectively, with 1.6-fold higher bulk N deposition. In addition, our findings indicate that while native prairie grasses may exhibit a positive biomass response to increased N deposition up to ~18 kg ha-1 yr-1, total inorganic N deposition is well above the estimated critical load for herbaceous plant species richness in the tallgrass prairie of the Great Plains ecoregion and thus may negatively affect these plant communities.

Utilizing mycorrhizal responses to guide selective breeding for agricultural sustainability

Societal Impact StatementAgriculture touches all aspects of society and global environmental health. Dwindling phosphorous reserves are a looming crisis for civilization, and soil erosion typically far outpaces pedogenesis. Improving plant–mycorrhizal symbioses can enhance sustainable agriculture because mycorrhizas typically improve host‐plant nutrition and stabilize soils. Selective breeding of plants that gain greater benefits from mycorrhizas can provide considerable economic and environmental benefits. Our assessments demonstrate switchgrass genetic improvement increased or maintained production of two populations, and low‐input breeding increased mycorrhizal responsiveness, compared to parent lines. Selecting for increased mycorrhizal reliance may be an effective strategy for more sustainable and economical agricultural production.Summary Plant–mycorrhizal interactions are not typically assessed in crop breeding programs. Our experiment addresses this by determining host‐plant outcomes of newly developed synthetic (agronomic) populations compared with parent lines, following low‐input selective breeding. Assessing the potential of low‐input breeding to enhance crop mycorrhizal benefits is a critical step toward more sustainable agricultural production. We compared four synthetic populations of Panicum virgatum, from a low‐input biofuel breeding program at Oklahoma State University, to corresponding parent lines. Plants were grown in a greenhouse in native prairie soils that were either steam‐pasteurized (nonmycorrhizal) or non‐steamed (mycorrhizal). We assessed shoot and root biomass, shoot P concentration and P content, mycorrhizal growth response (MGR), and mycorrhizal phosphorous response (MPR). Importantly, we provide novel evidence that low‐input selective breeding increased mycorrhizal reliance of switchgrass synthetics compared to parent lines, with implications for global agricultural systems. There are substantial opportunities for plant traits associated with increased MGR and MPR to be transferred to a wide array of crops. Our findings indicate low‐input selective breeding can improve MGR and MPR. We propose these traits serve as a useful proxy for host‐plant mycorrhizal reliance, facilitating successful hologenome breeding to reduce fertilizer requirements.

Evidence of Adaptation of Little Bluestem to the Local Environment of Central Kansas

Little bluestem is a North American grass species found in native prairie remnants which is used for range, pasture, CRP, and restoration planting. In this study we asked whether the distance between planting site and seed source influenced the growth and survival of little bluestem. In a collaborative project with high school teachers and students, we planted seed at 2 sites in central Kansas, from 7 sources ranging from 6.9 to 814 km distant from the planting sites. We found that our measures of fitness (survival and tiller number) together declined significantly with the distance of the seed source from the site. Our results suggest that local adaptation is important to little bluestem survival and productivity and therefore recommend that land managers seek local sources of seed for range or prairie plantings.

Origin of agricultural plant pathogens: Diversity and pathogenicity of Rhizoctonia fungi associated with native prairie grasses in the Sandhills of Nebraska.

The Sandhills of Nebraska is a complex ecosystem, covering 50,000 km2 in central and western Nebraska and predominantly of virgin grassland. Grasslands are the most widespread vegetation in the U.S. and once dominated regions are currently cultivated croplands, so it stands to reason that some of the current plant pathogens of cultivated crops originated from grasslands, particularly soilborne plant pathogens. The anamorphic genus Rhizoctonia includes genetically diverse organisms that are known to be necrotrophic fungal pathogens, saprophytes, mycorrhiza of orchids, and biocontrol agents. This study aimed to evaluate the diversity of Rhizoctonia spp. on four native grasses in the Sandhills of Nebraska and determine pathogenicity to native grasses and soybean. In 2016 and 2017, a total of 84 samples were collected from 11 sites in the Sandhills, located in eight counties of Nebraska. The samples included soil and symptomatic roots from the four dominant native grasses: sand bluestem, little bluestem, prairie sandreed, and needle-and-thread. Obtained were 17 Rhizoctonia-like isolates identified, including five isolates of binucleate Rhizoctonia AG-F; two isolates each from binucleate Rhizoctonia AG-B, AG-C, and AG-K, Rhizoctonia solani AGs: AG-3, and AG-4; one isolate of binucleate Rhizoctonia AG-L, and one isolate of R. zeae. Disease severity was assessed for representative isolates of each AG in a greenhouse assay using sand bluestem, needle-and-thread, and soybean; prairie sandreed and little bluestem were unable to germinate under artificial conditions. On native grasses, all but two isolates were either mildly aggressive (causing 5-21% disease severity) or aggressive (21-35% disease severity). Among those, three isolates were cross-pathogenic on soybean, with R. solani AG-4 shown to be highly aggressive (86% disease severity). Thus, it is presumed that Rhizoctonia spp. are native to the sandhills grasslands and an emerging pathogen of crops cultivated may have survived in the soil and originate from grasslands.

Long-term multidecadal data from a prairie-pothole wetland complex reveal controls on aquatic-macroinvertebrate communities

Interactions between climate and hydrogeologic settings contribute to the hydrologic and chemical variability among depressional wetlands, which influences their aquatic communities. These interactions and resulting variability have led to inconsistent results in terms of identifying reliable predictors of aquatic-macroinvertebrate community composition for depressional wetlands. This is especially true in the Prairie Pothole Region of North America where, in addition to pronounced climate variability, studies are often confounded by fish introductions. We used environmental monitoring data collected over a 24-year period from a complex of sixteen depressional wetlands and structural equation modeling techniques that incorporated theoretical and empirical relationships outlined in the Wetland Continuum to identify key environmental (climate and hydrogeologic setting) and biotic (competition and predation) drivers of aquatic-macroinvertebrate community composition for prairie-pothole wetlands. Uplands in the study area were primarily native prairie, thus, embedded wetlands were impacted minimally by agricultural influences. Additionally, study wetlands were predominately fishless. In the absence of the overwhelming influence of fishes, major drivers influencing aquatic-macroinvertebrate communities were revealed through the use of data spanning multidecadal-long climate cycles. We found variables related to the placement of wetlands along axes of the Wetland Continuum, e.g., hydrogeologic setting (relative wetland elevation) and hydroclimatic setting (proportion of wetland ponded), to be influential drivers of within-wetland habitat characteristics, such as the proportion of open-water area, which in turn was the strongest predictor of macroinvertebrate community composition. In contrast, predatory invertebrate and salamander abundance and non-predatory invertebrate biomass (i.e., predation and competition) were found to have minimal influence on community composition.

Balancing the need for seed against invasive species risks in prairie habitat restorations.

Adequate diversity and abundance of native seed for large-scale grassland restorations often require commercially produced seed from distant sources. However, as sourcing distance increases, the likelihood of inadvertent introduction of multiple novel, non-native weed species as seed contaminants also increases. We created a model to determine an “optimal maximum distance” that would maximize availability of native prairie seed from commercial sources while minimizing the risk of novel invasive weeds via contamination. The model focused on the central portion of the Level II temperate prairie ecoregion in the Midwest US. The median optimal maximum distance from which to source seed was 272 km (169 miles). In addition, we weighted the model to address potential concerns from restoration practitioners: 1. sourcing seed via a facilitated migration strategy (i.e., direct movement of species from areas south of a given restoration site to assist species’ range expansion) to account for warming due to climate change; and 2. emphasizing non-native, exotic species with a federal mandate to control. Weighting the model for climate change increased the median optimal maximum distance to 398 km (247 miles), but this was not statistically different from the distance calculated without taking sourcing for climate adaptation into account. Weighting the model for federally mandated exotic species increased the median optimal maximum distance only slightly to 293 km (182 miles), so practitioners may not need to adjust their sourcing strategy, compared to the original model. This decision framework highlights some potential inadvertent consequences from species translocations and provides insight on how to balance needs for prairie seed against those risks.

Genetic and Morphological Consequences of Inter-haplogroup Hybridization in Faxonius virilis

Faxonius virilis were sampled from native population and introduced populations within a narrow range of the South Saskatchewan River in southern Alberta. We hypothesize that introduced Great Lake F. virilis has hybridized with native prairie F. virilis. Tissue samples were taken for genetics, multiple specimens were collected to compare geometric morphometrics between the two known species and the hybrids. COI and GAPDH along with microsatellite markers show distinction within the grouping. The importance of this study is to identify populations of hybrids for future management plans.

Restorative recreation: One landowner's experience restoring a cedar‐infested native prairie remnant in Iowa's Loess Hills

Abstract Over 80% of pre‐settlement Iowa was a prairie landscape, but conversion and neglect has reduced that to less than 0.1% of the original 30 million acres (12 million hectares). Much of the remaining remnant prairie lies within the Loess Hills landform in western Iowa. Here I describe my experience as a landowner identifying and restoring a native Loess Hills prairie remnant overtaken by Eastern redcedar (Juniperus virginiana). Archived aerial photographs confirm its native remnant status and have been used to monitor restoration progress. Both shearing and hand clearing of cedars have been undertaken at this site, providing an opportunity to compare patterns of ecosystem recovery within one remnant prairie. I find that cedar shearing, though effective at rapidly clearing a large swath of land, was associated with greater abundance of weedy and woody species compared to hand clearing that occurred more gradually over a longer period of time. However, consistent, targeted herbicide application to woody growth, as well as two prescribed fires, have led to good recovery and stabilization of the grassland with minimal annual recruitment of new brush. Photographs of faunal associations with Pasque flowers (Anemone patens) provide an indicator of the biodiversity on this prairie and suggest Pasque flowers, due to their abundance at this site, function as a keystone species that drives early spring ecosystem productivity. Based on my experience, I introduce a paradigm called restorative recreation to provide a framework for integrating ecosystem restoration activities with outdoor recreation to maximize benefits to personal health and well‐being, while improving the landscape for other species that share our common home.

Effects of prescribed fire timing on grazing performance of yearling beef cattle, forage biomass accumulation, and plant community characteristics on native tallgrass prairie in the Kansas Flint Hills.

Recent research demonstrated that mid- or late-summer prescribed fires can be employed to manage sericea lespedeza (Lespedeza cuneata) infestations in the Kansas Flint Hills. The effects of prescribed fire applied during the growing season (i.e., August to October) on grazing performance of yearling cattle have not been evaluated. Native pastures (n = 18; 22 ± 4.0 ha) were grouped by watershed and assigned randomly to one of three prescribed-fire treatments: spring (7 April ± 2.1 d), summer (21 August ± 5.7 d), or autumn (2 October ± 9.9 d). Yearling beef cattle were grazed from May to August at a targeted stocking density of 280 kg live-weight/ha following prescribed-fire application. Forage biomass accumulations, soil cover, plant species composition, and root carbohydrate concentrations in four native plant species were evaluated. Total body weight (BW) gains and average daily gain were greater (P = 0.01) for cattle that grazed the spring and summer prescribed-fire treatments compared with those that grazed the autumn prescribed-fire treatment. As a result, final BW were greater (P = 0.04) in the spring and summer treatments than the autumn treatment. Conversely, forage biomass accumulations did not differ (P = 0.91) between fire regimes. Proportions of bare soil were greater (P < 0.01) in the spring treatment compared with the summer and autumn treatments, whereas proportions of litter on the soil surface were greater (P < 0.01) in summer- and autumn-burned pastures compared with spring-burned pastures. Total basal cover of graminoids and forbs did not differ (P ≤ 0.15) between prescribed fire treatments. Likewise, total basal cover of C3 or C4 perennial grasses did not differ (P ≥ 0.23) between prescribed-fire treatments. No treatment differences (P = 0.24) in root starch or root water-soluble carbohydrate concentrations in big bluestem (Andropogon gerardii), little bluestem (Schizachyrium scoparium), Indiangrass (Sorghastrum nutans), or purple prairieclover (Dalea purpurea) were detected. These data were interpreted to suggest that summer or autumn prescribed fire can be applied without reducing forage biomass accumulations, root carbohydrate concentrations in key native plant species, or considerably altering native plant populations compared with conventional spring-season prescribed fire; however, summer prescribed fire could be favored over spring or autumn prescribed fire both to maintain stocker cattle growth performance and to achieve control over sericea lespedeza.

Consumer roles of small mammals within fragmented native tallgrass prairie

AbstractGrassland ecosystems globally are being negatively impacted by changes in climate, disturbance regimes, nutrient flux, and consumer guilds. Changes in the trophic ecology of consumers can substantially influence local resources, contributing to shifting diversity, community turnover, and other processes of ecosystem change. Small mammals are diverse and abundant within grasslands and yet the impact of changing ecosystems on small mammals and the role of these mammals as consumers are still both under‐studied. We assessed small mammal resource use within grassland and woodland vegetation types that have resulted from landscape‐scale experimental disturbance through fire treatments within the tallgrass prairie ecoregion of the North American Great Plains. We predicted that resource use would vary significantly among grassland vs. woodland communities, in turn reducing the role of small mammals in contributing to future maintenance of native prairies. We sampled five dominant species of rodents across three years and multiple habitats. Using stable isotope analysis, we investigated isotopic niche area and overlap to infer variation in diet, both within and among species. Resource use shifted in bivariate isotopic space seasonally but not across years when combining all species and habitats. Inferred spring diet (based on fur samples) was highly diverse and overlapping. Summer isotopic values (based on liver tissue) in woody habitat treatments were narrower and overlapped less than within grassland habitats. Consumers generally shifted from C4 herbivory to C3 herbivory, or greater omnivory, when analyzing grassland, shrubland, and woodland habitats respectively. Within the tallgrass prairie ecosystem, small mammal populations in herbaceous‐dominated habitats use a broader variety of resources than small mammals in proximate woody‐dominated habitats. As native grasslands experience woody encroachment, small mammal assemblages experience turnover of dominant species and associated changes in diet. Ecosystem changes such as cessation of frequent fire resulting in more woody habitats may include reduced roles by native small mammals as consumers/dispersers/propagators of native grassland plants.

A comparison of plant communities in restored, old field, and remnant coastal prairies

Temperate grasslands are experiencing worldwide declines due to habitat conversion. Grassland restoration efforts are employed to compensate for these losses. However, there is a need to better understand the ecological effects of grassland restoration and management practices. We investigated the effects of three different grassland management regimes on plant communities of coastal prairie ecosystems in southwest Louisiana (the United States). We compared old fields, prairie remnants, and restored prairies. Coastal prairies are a unique type of grassland historically present across southeast Texas and southwest Louisiana. Old fields represent former coastal prairie habitats allowed to revegetate naturally without active management. Remnant coastal prairies are small, isolated patches of comparatively intact prairie. Restored coastal prairies have been actively restored by planting native coastal prairie vegetation and managed with prescribed burning, mowing, and/or removal of invasive non‐native species. Our work was conducted in three old fields, four remnants, and four restored prairies. Old fields were dominated by non‐native species with low conservation value, whereas remnant prairies were dominated by native species with high conservation value. Remnants had a mean species richness of 75 species per site, which is higher than most other tallgrass prairie ecosystems in North America. Restored sites were dominated by native species with high conservation value, although the composition differed between restored and remnant sites. Collectively, our results: (1) reinforce the importance of identifying and preserving remnant coastal prairies; and (2) show that restoration of degraded coastal prairies is a viable strategy for supporting the persistence of these unique grassland ecosystems.