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Effects of invasive exotic plants on plant communities are often profound, but interactions with higher trophic levels are less evident. Postulated effects of invasive plants on arthropods include increased abundances of herbivores through refuge and improved microclimate, facilitation of other exotic species, and altered arthropod diversity. We examined the impact on the arthropod community by Lespedeza cuneata, an exotic legume with dense, chemically defended foliage, by comparing arthropod numbers in unmanipulated 1-m2 plots with L. cuneata shoots (= control) to arthropod numbers in plots from which shoots of L. cuneata were removed. Lespedeza cuneata removal produced no overall effect on arthropod abundance, but an invasive herbivore, Popillia japonica (Japanese Beetle), was twice as abundant in plots with L. cuneata. Lespedeza cuneata removal increased arthropod evenness in May then decreased it through the summer. In a second experiment we quantified chewing herbivory by placing individual potted plants from five native prairie species and L. cuneata within these same removal/no removal plots for 4 weeks. Removal of L. cuneata shoots from plots did not significantly affect herbivory of tagged leaves from the native species. However, entire L. cuneata leaves or plants disappeared more frequently regardless of plot treatment. Invasion by this exotic legume is likely due to direct effects on native plants, but indirect effects through facilitation of an exotic herbivore could contribute to its success in some areas.

Invasive plant species may alter soil characteristics or interact with the soil microbial community resulting in a competitive advantage. Our objectives were to determine: i) if invasive plant species alter soil properties; and ii) the long-term effects of invasive plant species on soil properties and subsequent implications on ecological restoration efforts. We focused on Lespedeza cuneata, a plant that may be allelopathic. Soil samples were collected from four locations in Central Missouri, USA: an old-field with abundant L. cuneata, two reconstructed sites, and a remnant prairie that has never been plowed. Soil health indictors were used to characterize soil properties at these sites. Nearly every soil property differed significantly between the unplowed prairie reference site and the other three sites. The reconstructed sites, however, generally did not differ from the invaded old-field. These results indicate that the reconstructed prairies are not fully recovered. Although above-ground traits, such as the plant community structure, appear similar to the prairie, the soil microbial community structure still resembles that of an invaded old-field site. These results indicate that more time may be needed before soil microbial populations fully recover after invasive plant removal.

Most non-native domesticated plants provide benefits without escaping cultivation, but others have become prominent invaders. A better understanding of how domestication might alter plant traits that influence the ability of species to overcome barriers to invasion could improve invasion risk predictions. We explored how variation in foliar chemistry among cultivars of a widespread invader in the U.S. (Lespedeza cuneata) might influence invasion risk through differences in herbivore interactions and a potential tradeoff with competitive ability. In a no-choice feeding bioassay a generalist herbivore performed better when fed cultivars compared to wild genotypes and native congeners, suggesting domesticated L. cuneata may be more vulnerable to herbivory compared to wild genotypes. However, in a factorial greenhouse experiment, with treatments of herbivory and competition, all cultivars had similar seed and biomass production as the wild genotype. Competition with native species reduced productivity of all L. cuneata types, while experimental herbivory alone did not. We also found far less variation in foliar chemistry among L. cuneata types than expected based on domestication history. While our findings from the bioassay suggest potentially lower invasion risk for cultivars if herbivore populations expand more rapidly when feeding on cultivars, we did not find evidence that cultivars had different responses to herbivory or competition with native species in the greenhouse experiment. Altogether, the findings from our multi-pronged approach for evaluating potential factors underlying invasion success of a domesticated species indicate that domestication has not altered invasion risk of this widespread plant invader.

Restoration of native early successional plant communities in the eastern United States is a conservation priority because of declining populations of associated plants and wildlife. Restoration typically involves seeding native species and is often fraught with problems including weedy competition, expensive seed, and slow establishment. Pairing seed bank response with strategic herbicide applications may be an alternative approach for restoring these plant communities. We compared early successional plant communities established by seeding (SD) paired with selective herbicide use to natural revegetation (NR) from the seed bank paired with selective herbicide use at 18 locations that were previously row‐crop or tall fescue (Schedonorus arundinaceus) fields in Tennessee, Alabama, and Kentucky, the United States. We did not detect differences in species diversity and richness, coverage of non‐native grasses and forbs, or number and coverage of native flowering forbs by season between NR and SD treatments at tall fescue or fallow crop sites. Species evenness was greatest in NR and coverage of native‐warm‐season grasses in SD. Species richness and coverage of native forbs were least in untreated tall fescue units (CNTL). More flexibility to use herbicides with NR reduced coverage of sericea lespedeza (Lespedeza cuneata) in NR units compared to SD units at tall fescue sites. NR was 3.7 times cheaper than seeding. Land managers should consider using an NR approach to establish native early successional plant communities.

Restoration of plant communities can be hindered by the legacy of previously established invaders, despite their physical removal from the community. Current evidence, mainly built on short‐term greenhouse experiments, suggests that Sericea lespedeza (Lespedeza cuneata) invasion not only suppresses native plant species, but also alters soil conditions in host communities. As a result, L. cuneata may create a soil legacy that impedes plant community restoration. We examined the response of a Kansas grassland following L. cuneata removal to determine if historical L. cuneata abundance affected (1) plant community composition and (2) the establishment of additional native species. To address these questions, L. cuneata seeds were sown into 300 plots at a wide range of densities under different combinations of simulated disturbance and soil fertilization. After a three‐year establishment period, L. cuneata was removed from the community, and 13 native forb species were sown into all plots. Over 4 years, we found little evidence for a soil legacy effect that influenced community response post‐removal. Although there was a detectable relationship between community composition and L. cuneata, the variation explained by this relationship was very low. Similarly, the establishment of sown native species was unrelated to the historical abundance of L. cuneata. These results indicate that, regardless of initial density, L. cuneata does not impede plant community recovery in this system if effectively controlled within the first 3 years of invasion, and legacy effects inferred from greenhouse experiments may not translate to impacts on the plant community in the field.

We examined effects of the invasive species Lespedeza cuneata on native plants and foliar arthropod communities in a tallgrass prairie. Through observational and manipulative experiments, we examined plant and arthropod responses to L. cuneata over one growing season. The observational study found little impact of the invasive plant on arthropods. By the end of the manipulative experiment, the combined biomass of native grasses and forbs was reduced by approximately 50% in Lespedeza-present plots, while total arthropod numbers were only about 15% lower. Seasonal differences were evident; L. cuneata-absent plots showed lower arthropod numbers in May, but higher abundances in June. Some feeding groups, notably carnivorous arthropods, appeared unaffected by L. cuneata. We tested three hypotheses (one bottom-up and two top-down processes) to explain the relatively weak response of the arthropod community to the invasive plant. Nitrogen content of native plants adjacent to L. cuneata areas was significantly higher compared to plants more distant. Ground arthropod predators were higher during mid-summer in L. cuneata areas, which may partially explain seasonal variation in foliar arthropods. Insectivorous birds were unaffected by L. cuneata abundance, suggesting that arthropod predation rates by birds are unchanged. We suggest that while L. cuneata has strong effects on native plants, its ability to increase neighboring plant quality compensates for the lower biomass of native plants in L. cuneata areas, moderating the arthropod response. While management of this invasive species remains a priority, tallgrass prairie food webs may be partly resistant to L. cuneata invasion.

International audience; Henan Province is a major area of peanut production in China but the rhizobia nodulating the crop in this region have not been described. A collection of 217 strains of peanut rhizobia was obtained from six field sites across four soil types in Henan Province, North China, by using peanut as a trap host under glasshouse conditions. The 217 strains separated into 8 distinct types on PCR-RFLP analysis of their IGS sequences. Phylogenetic analysis of the 16S rRNA, recA, atpD, and glnII genes of 11 representative strains of the 8 IGS types identified Bradyrhizobium guangdongense, B. ottawaense and three novel Bradyrhizobium genospecies. Bradyrhizobium guangdongense was dominant, accounting for 75.0% of the total isolates across the field sites while B. ottawaense covered 5.1% and the three novel Bradyrhizobium genospecies 4.1 to 8.8% of the total. The symbiosis-related nodA and nifH gene sequences were not congruent with the core genes on phylogenetic analysis and separated into three groups, two of which were similar to sequences of Bradyrhizobium spp. isolated from peanut in south-east China and the third identical to that of B. yuanmingense isolated from Lespedeza cuneata in northern China. A canonical correlation analysis between the distribution of IGS genotypes and soil physicochemical characteristics and climatic factors indicated that the occurrence of IGS types/species was mainly associated with soil pH and available phosphorus.

We propose combining the filter framework model of community assembly with the passenger-driver model of non-native species behavior to help clarify the impacts of invasive species in the communities they invade and to guide sustainable management protocols. Observational field surveys and a greenhouse experiment explored the role of the invasive legume Lespedeza cuneata in the communities it invades and how natives in three functional groups&mdash, grasses, forbs, and legumes&mdash, respond to its presence. Within-site analyses from the field survey revealed differences in invaded and uninvaded areas in half of the sites, suggesting that site-specific characteristics influences whether L. cuneata&rsquo, s presence corresponds to local differences in species composition. The greenhouse experiment found higher levels of saprophytic and arbuscular mycorrhizal fungi in soil conditioned by L. cuneata than in unconditioned soil. However, competition between L. cuneata or the native congener L. capitata and nine native species illustrated stronger aboveground competitive effects than belowground soil effects due to soil conditioning, with impacts differing among functional groups. The response of L. cuneata was reduced in the presence of grasses and other legumes but not forbs. Assessing the impact of L. cuneata with the combined community assembly model revealed this invasive plant acts as a driver because it alters abiotic and biotic filters to impact species composition. Managing for high grass abundance and planting native legumes will help sustain grasslands from L. cuneata invasion.

Models for community invasion can inform grassland management if patterns involving the environment, other species, and invader success are evident. We evaluated unplanned invasion by Lespedeza cuneata into an experiment on a reconstructed tallgrass prairie. Our goal was to determine whether the pattern of invasion by this exotic legume was consistent with either the limiting similarity hypothesis (LSH), which predicts poorer establishment of exotic species in communities with related species, or the biotic resistance hypothesis, which predicts a negative association between species richness and invasion. We also examined how the abiotic environment and hemiparasite abundance affect spread of L. cuneata. From 2006 to 2015 we manipulated fertilizer and presence of the hemiparasitic plant, Pedicularis canadensis, in 1-m2 plots, and manipulated shade for the first 5 years. We found greater support for the LSH. Biomasses of legumes and other forbs in 2008 were negatively associated with change in L. cuneata biomass over the next 7 years but species richness was not a significant effect. Lespedeza cuneata cover in 2015 was lower in fertilized plots relative to unfertilized plots and was negatively associated with a composite variable that described the number and combined cover of legume species and number of exotic species currently in the plots. Shading for five seasons reduced L. cuneata growth, but only significantly in fertilized plots from which the hemiparasite had been removed. Other analysis suggested that L. cuneata increased more as the hemiparasite abundance increased. Prairie management that increases the kinds and abundances of native legume species and increases soil fertility may slow the spread of L. cuneata, but we caution against adding P. canadensis to large areas without greater knowledge of site-specific effects.

The genus Lespedeza (tribe: Desmodieae) consists of about 40 species that have high medicinal and economic value. However, in this genus, using morphological characters, the species identification is quite complicated, which can be solved by the analysis of the complete chloroplast genomes. As primary organelle genomes, the complete genome sequences of chloroplasts (cp) provide unique molecular information to study the divergence of species, RNA editing, and phylogeny. Therefore, to the best of our knowledge, for the first time, we sequenced the complete cp genomes of two representative Lespedeza species: Lespedeza davurica and Lespedeza cuneata. The cp genomes of both the species were found to be 149,010 bp in length, exhibiting the typical angiosperm chloroplast structure containing four regions. The Lespedeza cp genomes showed similar conserved gene contents, order, and orientations with a total GC content of 35.0%. A total of 128 genes, including 83 protein-coding genes, 37 tRNAs, and eight rRNAs, were identified from each genome. Unique molecular features of the two Lespedeza cp genome sequences were obtained by performing the analysis of repeats, sequence divergence, codon usage, and predicting the RNA editing sites in addition to phylogenetic analysis with other key genera in tribe Desmodieae. Using the two datasets, the phylogenetic relationship of Lespedeza species among Deasmodieae was discovered, suggesting that whole cp genomes provided useful information for phylogenetic studies of these species.

Control of invasive exotic species in restorations without compromising the native plant community is a challenge. Efficacy of exotic species control needs to consider collateral effects on the associated plant community. We asked (1) if short-term control of a dominant exotic invasive, Lespedeza cuneata in grassland restorations allows establishment of a more diverse native plant community, and (2) if control of the exotic and supplemental seed addition allows establishment of native species. A manipulative experiment tested the effects of herbicide treatments (five triclopyr and fluroxypyr formulations plus an untreated control) and seed addition (and unseeded control) on taxonomic and phylogenetic diversity, and community composition of restored grasslands in three sites over three years. We assessed response of L. cuneata through stem density counts, and response of the plant community through estimates of canopy cover. Herbicide treatments reduced the abundance of the exotic in the first field season leading to a less dispersed community composition compared with untreated controls, with the exotic regaining dominance by the third year. Supplemental seed addition did not provide extra resistance of the native community to reinvasion of the exotic. The communities were phylogenetically over-dispersed, but there was a short-term shift to lower phylogenetic diversity in response to herbicides consistent with a decrease in biotic filtering. Native plant communities in these grassland restorations were resilient to short-term reduction in abundance of a dominant invasive even though it was insufficient to provide an establishment window for native species establishment.

Surface coal mining and subsequent reclamation of surface mines have converted large forest areas into early successional vegetative communities in the eastern United States. This reclamation can provide a novel opportunity to conserve northern bobwhite (Colinus virginianus). We evaluated the influence of habitat management activities on nest survival, nest-site selection, and brood resource selection on managed and unmanaged units of a reclaimed surface mine, Peabody Wildlife Management Area (Peabody), in west-central Kentucky, USA, from 2010 to 2013. We compared resource selection, using discrete-choice analysis, and nest survival, using the nest survival model in Program MARK, between managed and unmanaged units of Peabody at 2 spatial scales: the composition and configuration of vegetation types (i.e., macrohabitat) and vegetation characteristics at nest sites and brood locations (i.e., microhabitat). On managed sites, we also investigated resource selection relative to a number of different treatments (e.g., herbicide, disking, prescribed fire). We found no evidence that nest-site selection was influenced by macrohabitat variables, but bobwhite selected nest sites in areas with greater litter depth than was available at random sites. On managed units, bobwhite were more likely to nest where herbicide was applied to reduce sericea lespedeza (Lespedeza cuneata) compared with areas untreated with herbicide. Daily nest survival was not influenced by habitat characteristics or by habitat management but was influenced by nest age and the interaction of nest initiation date and nest age. Daily nest survival was greater for older nests occurring early in the breeding season (0.99, SE

Range extensions to Butler County (Albizia julibrissin Durazz., Maclura pomifera (Raf.) C.K. Schneid., and Magnolia kobus DC.), Mercer County (Bellis perennis L.), Venango County (Lespedeza cuneata (Dum. Cours.) G. Don), and both Allegheny and Lawrence Counties (Arundinaria gigantea (Walter) Muhl.) are reported. All species are nonnative to Pennsylvania, and L. cuneata and A. julibrissin are considered invasive species in the commonwealth. The occurrence of M. kobus from a wet lowland forest in Butler County represents the first naturalized report of the species from the western half of the commonwealth. The reports of A. gigantea from Allegheny and Lawrence Counties are notable because they represent the second known occurrences of naturalized populations in Pennsylvania.

The developmental responses of insects to temperature are important considerations in gaining a better understanding of their ecology and life histories. Temperature-dependent phenology models permit examination of the effects of temperature on the geographical distributions, population dynamics, and management of insects. Measurements of insect developmental and survival responses to temperature pose practical challenges that depend on the chosen modality, variability among individuals, and high mortality rates near the lower and upper threshold temperatures. Different temperature levels can significantly affect larval development of Eurema hecabe. The development of E. hecabe reared on leaves of Lespedeza cuneata was investigated at three temperature regimes (20, 25, and 30°C), a relative humidity of 60%, and a light:dark photoperiod of 14:10 h. The developmental time from larva to adult was 34.3, 20.6, and 17.9 d at temperatures of 20, 25, and 30°C, respectively. Pupal rate was 47.6%, 47.6%, and 61.9% at temperatures of 20, 25, and 30°C, respectively. The developmental threshold temperature estimated from larva to pupae was 8.1°C with 381.7 degree-days. There is an increasing need for a standardized manual for rearing this butterfly species based on adequate knowledge of its ecology.

There is building interest in the use of ecological restoration to enhance the biotic invasion resistance of disturbed lands. However, few studies have rigorously examined the effect of community restoration on biotic invasion resistance under conditions of controlled invader propagule pressure. Results are presented from a field experiment conducted in a post-agricultural grassland in eastern Kansas to explore the interplay of tallgrass prairie restoration and invader propagule pressure in modulating plant invasion. Seed additions of multiple native and non-native species were used to provide a general test of biotic invasion resistance under varied propagule availability. Restoration increased plant diversity, increased above ground productivity, reduced the availability of light, soil moisture and bare soil microsites and strongly suppressed the invasion of all species sown into the experiment, including the highly invasive exotic legume, Lespedeza cuneata. In the absence of restoration, L. cuneata rapidly dominated plots where it had been sown, particularly at the highest propagule pressure. Results of multiple regression modelling suggested that restoration most likely increased community resistance to L. cuneata invasion through changes in functional guild composition rather than through changes in species diversity. Overall our study indicates that restoration of abandoned agricultural land to native tallgrass prairie can enhance invasion resistance in the face of substantial invader propagule pressures by altering community composition to dominance by native species that are efficient in utilizing resources.

More than 600,000 ha of mine land have been reclaimed in the eastern United States, providing large contiguous tracts of early successional vegetation that can be managed for northern bobwhite (Colinus virginianus). However, habitat quality on reclaimed mine land can be limited by extensive coverage of non-native invasive species, which are commonly planted during reclamation. We used discrete-choice analysis to investigate bobwhite resource selection throughout the year on Peabody Wildlife Management Area, a 3,330-ha reclaimed surface mine in western Kentucky. We used a treatment-control design to study resource selection at 2 spatial scales to identify important aspects of mine land vegetation and whether resource selection differed between areas with habitat management (i.e., burning, disking, herbicide; treatment) and unmanaged units (control). Our objectives were to estimate bobwhite resource selection on reclaimed mine land and to estimate the influence of habitat management practices on resource selection. We used locations from 283 individuals during the breeding season (1 Apr–30 Sep) and 136 coveys during the non-breeding season (1 Oct–Mar 31) from August 2009 to March 2014. Individuals were located closer to shrub cover than would be expected at random throughout the year. During the breeding season, individuals on treatment units used areas with smaller contagion index values (i.e., greater interspersion) compared with individuals on control units. During the non-breeding season, birds selected areas with greater shrub-open edge density compared with random. At the microhabitat scale, individuals selected areas with increased visual obstruction >1 m aboveground. During the breeding season, birds were closer to disked areas (linear and non-linear) than would be expected at random. Individuals selected non-linear disked areas during winter but did not select linear disked areas (firebreaks) because they were planted to winter wheat each fall and lacked cover during the non-breeding season. Individuals also selected areas treated with herbicide to control sericea lespedeza (Lespedeza cuneata) throughout the year. During the breeding season, bobwhites avoided areas burned during the previous dormant season. Habitat quality of reclaimed mine lands may be limited by a lack of shrub cover and extensive coverage of non-native herbaceous vegetation. Managers aiming to increase bobwhite abundance should focus on increasing interspersion of shrub cover, with no area >100 m from shrub cover. We suggest disking and herbicide application to control invasive species and improve the structure and composition of vegetation for bobwhites. © 2015 The Wildlife Society.

The North Carolina Division of Parks and Recreation manages 32,063 ha of coastal plain lands divided among 26 properties comprised of state parks, state natural areas, and a state recreation area. Of 35 invasive plant species found at 25 reporting sites, Japanese honeysuckle (Lonicera japonica) and privets (Ligustrum spp.) occurred most frequently, followed by sericea (Lespedeza cuneata), Japanese stiltgrass (Microstegium vimineum), alligatorweed (Alternanthera philoxeroides), Bermuda grass (Cynodon dactylon), common reed (Phragmites australis ssp. australis), silverberries (Elaeagnus spp.), mimosa (Albizia julibrissin), and wisterias (Wisteria spp.). Current management measures for these species and others include herbicide applications, hand pulling to intensively focused labor with equipment, or use of biological controls. These activities challenge missions, budgets, and staff time of each park unit such that early detection and rapid response are difficult. A dedicated staff position, an in...

Habitat management for northern bobwhite (Colinus virginianus) should affect vital rates, but direct linkages with survival are not well documented; therefore, we implemented an experiment to evaluate those responses. We conducted our experiment on a reclaimed surface mine, a novel landscape where conditions were considered sub-optimal because of the dominance of non-native vegetation, such as sericea lespedeza (Lespedeza cuneata), which has been reported to provide marginal habitat for northern bobwhite and may negatively affect survival. Nonetheless, these areas have great potential for contributing to bobwhite conservation because of the amount of early successional cover they provide. Our study site, a 3,330-ha reclaimed surface mine in western Kentucky, consisted of 2 tracts (Sinclair and Ken, 1,471 ha and 1,853 ha, respectively) that served as replicates with each randomly divided into a treatment (i.e., habitat manipulation through a combination of disking, burning, and herbicide application) and an undisturbed control (n = 4 experimental units). Habitat treatments were applied October 2009 to September 2013. We used radio telemetry to monitor northern bobwhite (n = 1,198) during summer (1 Apr–30 Sep) and winter (1 Oct–31 Mar), 2009–2013. We used the known-fate model in Program MARK to evaluate treatment effects on seasonal survival rates. We included biological, home-range, landscape, and microhabitat metrics as covariates to help improve model sensitivity and further elucidate experimental impacts. Survival varied annually, ranging from 0.139 (SE = 0.031) to 0.301 (SE = 0.032), and seasonally (summer, 0.148 [SE = 0.015]; winter, 0.281 [SE = 0.022]). We found a treatment effect (β = 0.256, 95% CI = 0.057–0.456) with a seasonal interaction (β = −0.598, 95% CI = −0.898 to −0.298) with survival being higher in summer (0.179 [SE = 0.022] vs. 0.109 [SE = 0.019]) and lower in winter (0.233 [SE = 0.025] vs. 0.355 [SE = 0.035]) on treatment than control units. Among habitat covariates, litter depth (β = −0.387, 95%CI = −0.5809 to −0.1930) was the most influential effect (negative) on survival. Additional experiments across a wider range of habitat conditions may be required to determine management intensity or duration thresholds required to elicit greater changes in survival for northern bobwhite populations. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.

Thirty-seven alien plant species, pre-identified by horizon scanning exercises were prioritised for pest risk analysis (PRA) using a modified version of the EPPO Prioritisation Process designed to be compliant with the EU Regulation 1143/2014. In Stage 1, species were categorised into one of four lists – a Residual List, EU List of Minor Concern, EU Observation List and the EU List of Invasive Alien Plants. Only those species included in the latter proceeded to the risk management stage where their priority for PRA was assessed. Due to medium or high spread potential coupled with high impacts twenty-two species were included in the EU List of Invasive Alien Plants and proceeded to Stage 2. Four species (Ambrosia trifida, Egeria densa, Fallopia baldschuanica and Oxalis pes-caprae) were assigned to the EU Observation List due to moderate or low impacts. Albizia lebbeck, Clematis terniflora, Euonymus japonicus, Lonicera morrowii, Prunus campanulata and Rubus rosifolius were assigned to the residual list due to a current lack of information on impacts. Similarly, Cornus sericea and Hydrilla verticillata were assigned to the Residual List due to unclear taxonomy and uncertainty in native status, respectively. Chromolaena odorata, Cryptostegia grandiflora and Sphagneticola trilobata were assigned to the Residual List as it is unlikely they will establish in the Union under current climatic conditions. In the risk management stage, Euonymus fortunei, Ligustrum sinense and Lonicera maackii were considered a low priority for PRA as they do not exhibit invasive tendencies despite being widely cultivated in the EU over several decades. Nineteen species were identified as having a high priority for a PRA (Acacia dealbata, Ambrosia confertiflora, Andropogon virginicus, Cardiospermum grandiflorum, Celastrus orbiculatus, Cinnamomum camphora, Cortaderia jubata, Ehrharta calycina, Gymnocoronis spilanthoides, Hakea sericea, Humulus scandens, Hygrophila polysperma, Lespedeza cuneata, Lygodium japonicum, Pennisetum setaceum, Prosopis juliflora, Sapium sebiferum, Pistia stratiotes and Salvinia molesta).

Eight eastern U.S. prairie sites were sampled for exotic species abundance in relation to levels of native diversity; including species and functional richness, species evenness, and functional group similarity for the alpha (quadrat; 1m2; n = 508) and gamma (site; n = 8) scales. Spearman's rank co- efficient analyses found only a weak negative correlation (P < 0.001; rs =–0.14) with species richness and exotic abundance; and was nonsignificant for the other measures of diversity. Principal Components Analysis (PCA) indicated instead that exotic abundance was more correlated with higher soil parameter values among the sites. Both Lonicera japonica and Lespedeza cuneata represented 90% of the exotic cover from among the study sites.

Lespedeza cuneata (sericea) is an Asian legume introduced to the US in the 1930s for erosion control and forage, but it can strongly reduce the abundance of native grassland plants. One possible explanation for this high invasive capacity is that L. cuneata is able to alter soil conditions to either improve its own growth, or reduce growth of native plants. To test for soil alteration following invasion, we collected soil from a previous 3-year field experiment in which L. cuneata was established in or excluded from randomly selected plots in a restored grassland. These soil history treatments were crossed with soil autoclaving—to disrupt microbial communities potentially important to plant interactions. For each treatment combination, a native plant, Sorghastrum nutans, was grown with L. cuneata or a conspecific in a 12-week greenhouse experiment. Although we found no evidence for competitive effects on the native species, L. cuneata biomass increased when grown in soil with a L. cuneata history as opposed to non-invaded soil (F 1, 16 = 4.79, P = 0.04). Additionally, nodulation of L. cuneata increased in invaded compared to non-invaded soil (F 1, 16 = 6.01, P = 0.026). These results indicate that, within three years of invasion, L. cuneata is able to alter soils to facilitate its own growth and suggest that at least part of the invasive success of L. cuneata is linked to altered soil conditions.

On the Ground • Supplemental polyethylene glycol (PEG), a polymer that neutralizes the negative effects of tannins, can increase intake and preference of cattle for fresh-cut sericea lespedeza (Lespedeza cuneata), an invasive, tannin-containing legume for the tallgrass prairie region of the Great Plains. • In grazing trials, steers supplemented with PEGI plus a high-protein supplement tended to eat more sericea than did steers only supplemented with the high-protein supplement. • Supplementing cattle with PEG, protein, or a combination of the two has the potential to enhance the amount of sericea consumed by cattle, contributing to the control of this weed.

The Aims of this study are to investigate ecological environments and indoor-rearing conditions of Eurema hecabe for artificial rearing. Two different nesting site, a open area nearby small river(A area; Daejin-ri, Gonyang-myeon, Sachun-si, Gyoungsangnam-do) and a foot of a hill area(B area; Noryang-ri, Seolcheon-myeon, Namhae-gun, Kyoungsangnam-do), selected for investigation of ecological habitat environment, and investigated two times per month, during six month, from June to November in 2010. In result, the number of butterflies, Eurema hecabe, at the hill area(B area) was 6 times more than the open area(A area). We observed the number of eggs, larvae and puapae in the B area more times compared to those in the A area. In the B area, Lespedeza cuneata was higher preference than the other host plant, Lespedeza pilosa and Albizia julibrissin. For development of indoor-rearing conditions, common grass yellow butterfly, Eurema hecabe, was reared in a room condition. As a result of oviposition preference experiment, 100-mated-female laid significantly higher number of eggs on Lespedeza cuneata plant, whereas the number of eggs was on Cassia obtusifolia plant. Moreover, the eggs hatched within days from the day of oviposition and procent of egg hatchability was 53.7% on host plant. The headwidth of each developmental larval stage were (1st), (2nd), (3rd), (4th), (5th). The larval period was days under high temperature, long day condition(, 16L : 8D), showing 81.0% pupal ratio. The pupal period was days, and the emergence rate was 79.6%. Based on above experiment, artificial rearing system of common grass yellow butterfly, Eurema hecabe was completed in indoor condition.

There is growing interest in whether invasive species may be controlled by utilizing management strategies that target vulnerable life stages. We manipulated the timing of fire and measured its effects on sericea lespedeza germination and seedling survival. Although fire strongly decreased germination in the laboratory, fire increased germination under field conditions. Additionally, fire caused small decreases in seedling survival in the field. Therefore, controlled burns are likely to encourage spread of sericea lespedeza and are unlikely to effectively control this invasive species. Although targeting vulnerable life stages is a promising strategy for invasive species control, our results illustrate that system-specific studies may be needed to unravel potentially complex interactions between biotic and abiotic factors before effective control strategies can be devised. Nomenclature: Sericea lespedeza, Lespedeza cuneata (Dum. Cours.) G. Don Management Implications: Sericea lespedeza is a noxio...

Invasive plant species can modify soils in a way that benefits their fitness more than the fitness of native species. However, it is unclear how competition among plant species alters the strength and direction of plant–soil feedbacks. We tested how community context altered plant–soil feedback between the non-native invasive forb Lespedeza cuneata and nine co-occurring native prairie species. In a series of greenhouse experiments, we grew plants individually and in communities with soils that differed in soil origin (invaded or uninvaded by L. cuneata) and in soils that were live vs. sterilized. In the absence of competition, L. cuneata produced over 60% more biomass in invaded than uninvaded soils, while native species performance was unaffected. The absence of a soil origin effect in sterile soil suggests that the positive plant–soil feedback was caused by differences in the soil biota. However, in the presence of competition, the positive effect of soil origin on L. cuneata growth disappeared. These results suggest that L. cuneata may benefit from positive plant–soil feedback when establishing populations in disturbed landscapes with few interspecific competitors, but does not support the hypothesis that plant–soil feedbacks influence competitive outcomes between L. cuneata and native plant species. These results highlight the importance of considering whether competition influences the outcome of interactions between plants and soils.

Twenty-four yearling Boer (87.5%) × Spanish wethers (32.5 ± 0.36 kg body weight) were used in a 32 d experiment to assess effects of frequency of feeding condensed tannin (CT)-containing Sericea lespedeza (SL; Lespedeza cuneata) on ruminal methane emission. Fresh SL (153 g/kg CT) was fed at 1.3 times the metabolizable energy requirement for maintenance every day (1SL), other day (2SL), fourth day (4SL), and eighth day (8SL), with alfalfa (Medicago sativa) offered at the same level on other days. Ruminal fluid for microbial assays was collected 1 d after SL feeding and at the end of the feeding interval (short and long interval samples, respectively). Dry matter intake was not affected by frequency of SL feeding. Daily ruminal methane emissions increased at a decreasing rate (Linear and Quadratic; P

Invasive plant species can potentially exert competitive or facilitative effects on insect pollination services of native species. Factors that influence these effects include the degree of shared pollinator species, synchronous flowering phenology, similar flower morphology and color, relatedness of invasive and natives, and showiness and densities of flowers. We investigated such plant-pollinator dynamics by comparing the invasive Lespedeza cuneata and three native congeners, all sympatric with synchronous flowering, using in situ populations over 2 years during peak floral displays. Insect visitation rates of the invasive were significantly higher per plant in both years than on the native species. The invasive exerted a competitive effect on visitation of the two native species with fewer shared pollinators, and a facilitative effect on visitation of the native species with the highest degree of shared insect visitors. Positive correlations were found between floral density and visitation rate per plant in all the native species. Although no such correlation was found for the invasive, floral density in L. cuneata was at least twenty times higher than in the native species and likely saturated the response of the pollinator community. Analyses of insect visitor taxonomic data indicated the insect communities visiting each of the Lespedeza species were generally similar though with species-specific differences. The main exception was that the common honeybee, Apis mellifera, was a primary visitor to the invasive plant species, yet was never observed on the native Lespedeza species.

Th e evolution of increased competitive ability (EICA) hypothesis provides a compelling explanation for the success of invasive species. It contends that because alien plants have escaped their coevolved natural enemies, selection pressures favor a diversion of resources from herbivore defense to traits that confer increased competitive ability. Here, we provide evidence for EICA in the noxious grassland invader Lespedeza cuneata , by comparing the ancestral genotype introduced to North America in 1930 with modern-day invasive (North American) and native (Japanese) genotypes. We found that the invasive genotype was a better competitor than either the native or the ancestral genotype. Further, the invasive genotype exhibited greater induced resistance but lower constitutive resistance than the ancestral and native genotypes. Our results suggest that selection has played a pivotal role in shaping this invasive plant species into a more aggressive, but less constitutively defended competitor. Th e rapid population growth and high densities reached by invasive species provides scientists with many opportunities to investigate the mechanisms that regulate the abundance and distribution of organisms. Such research is a conservation priority since invasive species cause signifi cant environmental and economic damage, and pinpointing the mechanisms that allow invasive species to achieve community dominance

Aims In this study, we examined the effects of Solidago altissima (hereafter Solidago) and two species in the genus Verbesina, Verbesina virginica and Verbesina occidentalis (hereafter Verbesina), on the structure of an old-field plant community and establishment by an invasive plant species, Lespedeza cuneata (hereafter Lespedeza). Materials and Methods We removed Solidago, Verbesina and both Solidago and Verbesina from 4-m 2 plots in an intact old-field community during two growing seasons. We then quantified the effects of these removals on richness, evenness, diversity and composition of the subdominant plant community. We also measured the total aboveground biomass and the aboveground biomass of the subdominant community. To assess how these removals affected establishment by Lespedeza ,w e planted 20 seeds in each plot and tracked seedling emergence and survival for one growing season. Important Findings Subdominant community evenness and Shannon diversity were higher in plots from which Solidago and Verbesina were removed relative to control plots. However, there were no effects of dominant species removal on species richness or composition of the subdominant community. Total aboveground biomass was not affected by dominant species removal, suggesting that the community of subdominant species exhibited compensation. In fact, subdominant community biomass was greater when Solidago, but not Verbesina, was removed. Light availability was also greater in plots where Solidago was removed relative to control plots throughout the growing season. In addition, removal of dominant species, in particular Solidago, indirectly reduced the emergence, but not survival, of Lespedeza seedlings by directly promoting subdominant community biomass. Taken together, our results suggest that dominant old-field plant species affect subdominant community structure and indirectly promote establishment by Lespedeza.

Research in community invasibiliy has focused on biotic and abiotic factors that influence the establishment of invasive species and whether such factors vary with spatial scale. Here, we investigate the role of both biotic and abiotic factors associated with the initial establishment of Lespedeza cuneata (L. cuneata) and its abundance at three spatial scales: neighborhoods (9-m2 plots), communities (50-m2 transect) and old fields (5,000–70,000 m2). We asked: (1) Do resource availability and community structure affect the establishment of L. cuneata?, and (2) Are resource availability and community structure associated with patterns of L. cuneata abundance from neighborhood scales to old-field scales? To investigate the first question, we manipulated soil nitrogen (N) availability at three levels in an existing old-field community and tracked emergence and persistence of L. cuneata seedlings, as well as total plant biomass of the community, availability of light, and soil moisture content. To address the second question, we performed surveys in which we estimated L. cuneata foliar cover at community scales (50-m2 belt transects) and old-field scales (total area of 28 ha), and assessed the same biotic and abiotic variables as in the field experiment. The experiment revealed that establishment and persistence by L. cuneata seedlings were 15× and 5× lower in N-added plots than in N-reduced plots. Total plant community biomass was 30% greater in N-added plots than in N-reduced plots. Conversely, light and soil moisture were 60 and 20% lower in N-added plots than in N-reduced plots. Surveys of old fields indicated that community biomass was positively associated with L. cuneata cover at old-field scales likely resulting from greater soil N input from nitrogen fixation in fields with greater L. cuneata cover. In sum, these results indicate that biotic factors associated with establishment of a Rank 1 invasive plant species at the community scale are also related to its distribution at the old-field scale, but the direction of such associations changed across scales.

It is well known that soil microbial communities reestablish following disturbance, but limited research has been done on how long this takes in eastern reclaimed coal mine soils. The objective of this study was to track the development of total microbial biomass in reclaimed mine soils following coal mining in southwestern Virginia. A chronosequence of sites was established based on locally documented shifts in vegetation species with succession (0-2, 5-7, 18-20, and 38-42 yr old) on reclaimed sites with undisturbed adjacent sites used as a reference. The 0-2 yr old sites were covered with annual and perennial grasses and forbs, the 5-7 yr sites by thick stands of Lespedeza cuneata, the 18-20 yr sites predominately with Festuca arundinaceae and patches of deciduous trees, and the 38-42 yr old sites with a mix of planted conifers and native Appalachian hardwoods with a grass understory. Undisturbed sites predominately supported mixed Appalachian hardwoods with a mixed forb/grass understory. Four samples were taken from each site age (3 replicates) at the 0-5 cm depth. Chloroform-fumigation- extraction was used to determine total organic carbon from lysed microbial cells as a proxy for microbial biomass. Microbial biomass carbon (MBC) did not vary significantly among any of the site ages sampled; however, a general trend of increasing MBC from a low level in the more recently reclaimed sites (131-138 g microbial C kg -1 soil) to a higher level of MBC in the 16-20 and 38-42 yr sites (280 and 244 g microbial C kg -1 soil, respectively) was observed. This indicated a recovery of soil microbial communities with time; possibly well within the 5-year vegetation liability release period mandated by the Surface Mining Control and Reclamation Act (SMCRA).

To better understand the strategies and mechanisms of invading plants in tallgrass prairie, physiological and morphological characteristics of the invasive Lespedeza cuneata were compared to the dominant and abundant natives Ambrosia psilostachya and Andropogon gerardii. Gas exchange, chlorophyll fluorescence, plant water status, and total and specific leaf area were quantified in the field for each species both throughout daily sampling periods and across the growing season. Total and specific leaf area (cm2 g−1 of leaves) exceeded that of native species and may allow L. cuneata to successfully establish and dominate in tallgrass prairie, aiding in both resource acquisition and competitive exclusion. Gas exchange traits (e.g. net photosynthesis, stomatal conductance, and water use efficiency) of L. cuneata did not exceed other species, but remained constant throughout the daily sampling periods. The daily consistency of net photosynthesis and other gas exchange traits for L. cuneata reveal characteristics of stress tolerance. The combination of these characteristics and strategies may assist in the invasion of L. cuneata and also provide insight into general mechanisms responsible for successful invasions into tallgrass prairie.

Some exotic plants are able to invade habitats and attain higher fitness than native species, even when the native species are closely related. One explanation for successful plant invasion is that exotic invasive plant species receive less herbivory or other enemy damage than native species, and this allows them to achieve rapid population growth. Despite many studies comparing herbivory and fitness of native and invasive congeners, none have quantified population growth rates. Here, we examined the contribution of herbivory to the population dynamics of the invasive species, Lespedeza cuneata, and its native congener, L. virginica, using an herbivory reduction experiment. We found that invasive L. cuneata experienced less herbivory than L. virginica. Further, in ambient conditions, the population growth rate of L. cuneata (lambda = 20.4) was dramatically larger than L. virginica (lambda = 1.7). Reducing herbivory significantly increased fitness of only the largest L. virginica plants, and this resulted in a small but significant increase in its population growth rate. Elasticity analysis showed that the growth rate of these species is most sensitive to changes in the seed production of small plants, a vital rate that is relatively unaffected by herbivory. In all, these species show dramatic differences in their population growth rates, and only 2% of that difference can be explained by their differences in herbivory incidence. Our results demonstrate that to understand the importance of consumers in explaining the relative success of invasive and native species, studies must determine how consumer effects on fitness components translate into population-level consequences.

Non-native species are hypothesized to decrease native species establishment and cover crops are hypothesized to decrease non-native species abundance. Although many studies have compared invaded to non-invaded habitats, relatively few studies have experimentally added non-native species to directly examine their effects. In a greenhouse mesocosm experiment, we tested the effects of non-native forbs (Melilotus officinalis, Verbascum thapsus, and Lespedeza cuneata), a proposed C3 grass cover crop (Pascopyrum smithii), and a commonly seeded non-native C3 grass (Bromus inermis) on the establishment of target native C4 prairie grass species. All treatments contained the same seed density of target C4 species and were begun on bare soil collected from the field. The legume M. officinalis strongly decreased the abundance of all other species, species diversity, and light and soil moisture levels. Surprisingly, M. officinalis took up relatively large amounts of labeled nitrogen (15N) from the soil early in its development, but M. officinalis fixed nitrogen, thus increasing nitrogen in biomass nearly fivefold by the end of the study. We found few effects of either C3 grass species on non-native forbs or C4 target species, but seeded P. smithii did increase species diversity. Non-native plants therefore impeded native C4 grass establishment through long-lasting effects of target species seedbank depletion (death of most target seedlings) and altered nutrient availability. The effects of M. officinalis were not reduced by the presence of a cover crop.

Comparative studies of congeneric native and exotic species have proved fruitful in understanding plant traits that foster invasion. Using this approach, we investigate the complex reproductive system of the invasive Lespedeza cuneata (Dum.-Cours.) G. Don in relation to three native congeners in the variable environment of the North American tallgrass prairie. Lespedeza species produce both chasmogamous (CH) and cleistogamous (CL) flowers, and propagate clonally via vegetative buds. Utilizing multiple natural populations over 2 years, we investigated reproductive modes of individuals from bagged and unbagged treatments of each species. We found that L. cuneata produced a mean of five times as many seeds and a significantly greater number of vegetative buds than any native studied, and over twenty times as many CH flowers. Insect visitation significantly affected seed set in CH flowers, though some autonomous CH selfing occurred in all species. The invasive relied relatively less on selfing than the natives and exhibited less variation in reproductive output from both modes of reproduction. We conclude that the diverse reproductive biology and wide regeneration niche of L. cuneata in relation to its native congeners confer a fitness homeostasis that facilitates the successful spread of this invasive under a wide range of conditions.

Invasive species are a global threat to biodiversity and the functioning of natural ecosystems. Here, we report on a two-year experiment aimed at elucidating the combined and relative effects of three key controls on plant invasions: propagule supply, soil nitrogen (N) availability, and herbivory by native insects. We focus on the exotic species Lespedeza cuneata, a Rank 1 invasive species. Propagule supply and soil N-availability interacted to control the density and foliar cover of L. cuneata. In low N plots, density and foliar cover of L. cuneata were higher in the propagule addition plots than in the plots to which propagules were not added. Surprisingly, this interaction was significant only when the abundance of herbivores was experimentally reduced. This experiment provides evidence that native insect herbivores mediate the interactive effects of propagule supply and resources on invasion by a widespread invasive plant species.

Invasive species pose significant ecological costs, and therefore successful management techniques are important. One commonly employed method is biological control. The success of biological control depends largely on whether additional inflicted damage can successfully reduce the fitness and population growth rate of a target species. Here, we simulate herbivory on the invasive Lespedeza cuneata and create stage-structured projection models to determine if augmented herbivory by a leaf-chewing biological control agent would regulate the population growth rate of this species. We found that augmented herbivory influenced stage transitions of plants in the smallest stage class, causing higher mortality and reduced growth. No other effect was found on stage transitions or fecundities, despite manipulation of herbivory at exceptionally high levels (up to 80% leaf loss). None of the clipping treatments significantly reduced the population growth rate of L. cuneata. We conclude that biological control by a leaf chewing herbivore would not likely be successful, even if an exceptionally large amount of each plant were consumed. We suggest that this approach, a combination of simulated herbivory and demographic modeling, will provide essential information for understanding the utility of biological control to curb the population growth of invasive plant species.

Invasion of rangeland by exotic forage species threatens ecosystem structure and function and can cause catastrophic economic losses. Herbicide treatments often are the focus of management efforts to control invasions. Management with the fire-grazing interaction (or patch burning) might suppress an invasive forage species that has grazing persistence mechanisms developed apart from the fire-grazing interaction. We studied tallgrass prairies invaded by sericea lespedeza (Lespedeza cuneata [Dum.Cours.] G. Don) to compare rate of invasion between traditional management and management with patch burning, to evaluate the effect of burn season on sericea lespedeza invasion within pastures managed with patch burning, and to correlate canopy cover of sericea lespedeza to canopy cover of other functional groups with and without herbicides. Sericea lespedeza canopy cover increased from 1999 to 2005 in both traditional- and patch-burn pastures, but sericea lespedeza increased from 5% to 16% canopy cover in traditionally managed pastures compared to 3% to 5% in the patch-burn pastures. Rate of increase in canopy cover of sericea lespedeza was less in patches burned in summer (0.41% ? year 21 ) than in patches burned in spring (0.58% ? year 21 ) within patch-burn pastures. Most plant functional groups, including forbs, were weak-negatively correlated with canopy cover of sericea lespedeza. Although herbicide application reduced mass of sericea lespedeza, other components of the vegetation changed little. Herbicide treatments temporarily reduced sericea lespedeza but did not predictably increase other plant functional groups. Patch burning reduced the rate of invasion by sericea lespedeza by maintaining young, palatable sericea plants in the burn patch, and could play a vital role in an integrated weed management strategy on rangelands.

Sericea lespedeza has been an important forage legume in portions of the USA for decades but has recently been recognized as invasive in some ecosystems. Stand characteristics potentially affecting usefulness and invasiveness were assessed on forested and open sites of a Louisiana Coastal Plain landscape. Typical heavy weed competition, which was not overcome by increased seeding rate or extent of seedbed preparation, occurred in full sunlight. An open longleaf pine canopy suppressed competitive herbaceous species and enhanced establishment compared to that in full sunlight. Shade of either longleaf pines or dense overstory of tall weeds reduced productivity but not stands. Sericea lespedeza spread was limited to a few meters during 7 years, apparently due to lack of an effective dispersal mechanism. Long stand life under mature longleaf pines and in the open field along with ability to re-colonize from soil seed reserves contribute to both usefulness of sericea lespedeza for conservation, forage, and wildlife habitat in agricultural landscapes and potential undesired persistence, especially with land-use changes to less intensive management, on Louisiana Coastal Plain landscapes.

A two-year floristic survey of the 7,690-ha Pushmataha Wildlife Management Area (PWMA) located in the Kiamichi Mountains of southeastern Oklahoma revealed the known vascular flora to comprise 447 species in 287 genera and 97 families. The four largest families—Poaceae, Asteraceae, Fabaceae, and Cyperaceae—compose 43.4% of the flora. The largest genera are Carex, Juncus, Dichanthelium, Desmodium, and Lespedeza. Native species account for 92.8% of the taxa. Three introduced species appear to be naturalizing in the area: Elaeagnus angustifolia, Lespedeza cuneata, and Sorghum halepense. Thirteen species designated as rare by the Oklahoma Natural Heritage Inventory were encountered: Dulichium arundinaceum, Justicia ovata var. lanceolata, Brachyelytrum erectum, Calamovilfa arcuata, Piptochaetium avenaceum, Smilax smallii, Ilex opaca, Ribes cynosbati, Tilia americana var. caroliniana, Polygala polygama, Carex oxylepis, Carex oklahomensis, and Mitchella repens.

Sericea lespedeza [Lespedeza cuneata (Dumont) G. Don] is a non-native invasive plant that threatens the health of prairie and rangeland. A survey of rangeland in Cowley County, Kansas, was conducted to determine the spatial distribution, level of infestation, and estimated treatment cost. In addition, patterns of water distribution, soil type and forest cover were examined to determine if some areas were at a higher risk of invasion by sericea lespedeza. Sixty-six randomly determined quarter-sections were surveyed in the county by running two 800-meter transects at each location. Each transect was 2 m wide and consisted of 8 subsections. From these samples, it was determined that approximately 26,000 hectares (17%) of rangeland in the survey area contained sericea lespedeza. The levels of infestation ranged from sparse to severe. Sparse and scattered were the most frequent levels, and when combined, were found in 50% of the infested survey sites. The estimated cost for a one-year treatment is $18...

Researchers studying invasive plants often concentrate their efforts on predictive models thought to allow invasive plants to dominate native landscapes. However, if an invasive is already well established then experimental research is necessary to provide the information necessary to effectively manage the species. Prescribing appropriate management strategies without prior experimental research may not only be ineffective but also may squander limited resources or have the unintended consequence of furthering spread. Lespedeza cuneata(Dum. Cours.) G. Don. is a well-established invasive plant of old fields and tall-grass prairie in the US. Managers suspect this species shades-out native plants and this is proposed as its primary mechanism for dominance. Using field experiments we tested probable factors allowing the species to establish itself and, once established, interfere in old field plant communities. We also examined the effects of two common anthropogenic disturbances (mowing and nutrients) on L. cuneata growth and establishment. When L. cuneata was treated (clipping, herbicide and stem pull-back) there was a significant increase in species richness and native species cover. Stem density and canopy cover of L. cuneata increased significantly with mowing frequency but decreased with nutrient input. We suggest that mowing benefits L. cuneata while also hindering woody competition. Results also indicate L. cuneata is less prevalent on nutrient enriched soils than on unamended soil. Lespedeza cuneata appears to suppress native plants by shading them out and it can subsequently take over grassland communities. Since it has a varying response to human induced disturbances and may actually benefit from mowing, land managers should be cautious when utilizing this as a management tool.

A six-year-old restored prairie plant community at Johnson County Community College (JCCC) was monitored for changes in species number and plant cover. It was hypothesized that haying would successfully establish a prairie plant community, and that all seeded species would grow. In 1994 a 0.5 ha area was sprayed to remove weeds, and then seeded with eleven forb and six grass species. The seed mix included generalists that do not require high-quality habitats, and conservatives that do. Beginning in late fall 1995 the area was annually mowed and litter removed (hayed). By 1998 species number was 28, but dropped to 24 in 2001. Species composition included only some of the seeded species, and additional species not in the original mix. Seven of the original forb species were generalists, yet were absent. All six grasses were present. Total cover for all forbs decreased, but not significantly. Cover of the invasive weed Lespedeza cuneata increased in 2001, albeit not significantly. Total cover of all...

Cades Cove, Great Smoky Mountains National Park, U.S.A. was historically cleared largely for pastoral purposes; it is now comprised of recently abandoned pastures dominated by non-native pasture species. To investigate the potential for reducing non-native species relative to native species, park managers initiated an experiment in 1995 that included mowing, herbicide application, planting of seed, and burning of replicate 20 × 50–m plots at each of two sites within Cades Cove. Between 1995 and 2001 we evaluated the response of the plant community (i.e., species-specific cover and frequency, biomass, diversity) to this suite of treatments and compared it with unmanipulated control plots at each site. Four years after treatment initiation abundance measures of Plantago lanceolata, Setaria geniculata, and Trifolium spp. averaged one-third lower in treated than control plots. Frequency of Festuca pratensis was lower in treated than in control plots for 2 years, but after 4 years its frequency, cover, and biomass did not differ between treated and control plots. By 2000 the cover of Sorghastrum nutans in treated plots increased to 23–47%, depending on the site. Total biomass and diversity increased in treated plots. The dominance of Lespedeza cuneata at one site apparently reduced planting success, biomass production, and diversity and evenness. Post-treatment lags in response for several species, coupled with interannual variation in response to environmental conditions, suggest that evaluations of treatment success would differ greatly depending on when the evaluation was conducted.

Although invasion risk is expected to increase with propagule pressure (PP), it is unclear whether PP-invasibility relationships follow an asymptotic or some other non-linear form and whether such relationships vary with underlying environmental conditions. Using manipulations of PP, soil fertility and disturbance, we tested how each influence PP-invasibility relationships for Lespedeza cuneata in a Kansas grassland and use recruitment curve models to determine how safe sites may contribute to plant invasions. After three growing seasons, we found that the PP-invasibility relationships best fit an asymptotic model of invasion reflecting a combination of density-independent and density-dependent processes and that seeds were aggregated within the plant community despite efforts to uniformly sow seeds. Consistent with some models, community invasibility decreased with enhanced soil fertility or reduced levels of disturbance in response to changes in the fraction of safe sites. Our results illustrate that disturbance and soil fertility can be a useful organizing principle for predicting community invasibility, asymptotic models are a reasonable starting point for modeling invasion, and new modeling techniques—coupled with classic experimental approaches—can enhance our understanding of the invasion process.