Microstegium Vimineum Research Articles

Comparison of Torching and Glyphosate Applications for Japanese Stiltgrass (Microstegium vimineum) Control

Abstract Trials were conducted over three years to evaluate two torchings, torching followed by glyphosate application, raking followed by glyphosate application, and one or two yearly applications of glyphosate for control of Japanese stiltgrass. A single glyphosate application in fall reduced Japanese stiltgrass cover but the percent cover increased during the following growing season. Either two torchings or two applications of glyphosate per season for three years gave excellent Japanese stiltgrass control but plants recovered the year after treatments ended. Raking away leaf litter in spring increased Japanese stiltgrass cover. Torching followed by a glyphosate application was less effective than 2 applications of glyphosate. Treatments would need to be repeated for over three years to eradicate Japanese stiltgrass from a site. Species used in this study: Japanese stiltgrass, Microstegium vimineum (Trin.) A Camus.

Citizen science and land use data provide insight into the invasive riparian plant composition of the Hudson River Valley watershed

AbstractInvasive plants in the riparian zone can negatively affect the characteristics and quality of a watershed. To support the development of a watershed management plan and foster public appreciation of the value of the riparian zone, Mohonk Preserve established a volunteer monitoring program surveying sites for invasive species. Between 2017 and 2019, citizen scientists repeatedly surveyed 20 sites in the Hudson River Valley in New York for 10 invasive plant species: purple loosestrife (Lythrum salicaria L.), common reed [Phragmites australis (Cav.) Trin. ex Steud], multiflora rose (Rosa multiflora Thunb.), garlic mustard [Alliaria petiolata (M. Bieb.) Cavara & Grande], dame’s rocket (Hesperis matronalis L.), Japanese knotweed (Polygonum cuspidatum Siebold & Zucc.), wineberry (Rubus phoenicolasius Maxim.), barberry (Berberis spp.), Japanese stiltgrass [Microstegium vimineum (Trin.) A. Camus], and Asiatic bittersweet (oriental bittersweet, Celastrus orbiculatus Thunb.). We found that the number of target species detected was higher on sites closer to paved roads and with increasing drainage area size, while lower with higher percentages of forested land in the basin. Our analysis results highlight variation in the presence of target invasive species across the Hudson River Valley region, highlighting sites and areas to monitor for future introductions and take action to prevent species’ invasions. Our results highlight differences in the most relevant abiotic factors for hydrophytes and non-hydrophyte species, underscoring the importance of considering species’ life-history traits before the development of management plans for invasive plant species in the riparian zone. Our case study of community-collected data in the Hudson River Valley region using a relatively simple monitoring protocol can provide a road map for other regions fostering volunteer engagement with invasive plants.

First report of Curvularia intermedia Boedijn causing leaf blight disease on Microstegium vimineum in China.

Stiltgrass [Microstegium vimineum (Trin.) A. Camus], is an annual C4 grass of Asiatic origin whose native range includes India, Pakistan, Nepal, China, Korea, and Japan (Cole et al 2004). In China, it is mainly distributed south of the Yangtze River, and is one of the most important weeds in autumn-maturing dryland crops, orchards, tea gardens, and plantations. With its high shade tolerance, M. vimineum also invades forest understories and crowds out the local vegetation (Warren et al. 2011). From June to August 2019, a leaf disease was observed causing severe defoliation of stiltgrass on the roadside of Sun Yat-sen Mausoleumin Nanjing City, Jiangsu Province, China (32.045964°N, 118.840064°E). Yellow or yellow-brown necrotic spots were observed on leaf tips and margins of the lower canopy, which later expanded to the entire leaf and progressed up the plant. Disease incidence was approximately 75-85% in August. Thirty symptomatic leaves were collected, and tissue samples (5 × 5 mm) were surface disinfected with 75% ethanol for 30 s, 0.02% NaClO for 30 s, 75% ethanol for 30 s, and washed twice with sterile water. Disinfected tissues were placed on potato dextrose agar (PDA) and incubated at 28°C for 5 days. Twenty-seven morphologically similar isolates were obtained from the leaves and purified by single-spore culturing for further study. Colonies on PDA were 70 to 85 mm in diameter after 4 to 5 days, initially white becoming gray-green with flocculent aerial mycelia. Conidiophores were solitary or clustered, 85 to 139 µm long × 5 to 8 µm wide (n = 50), and conidia were obclavate to ellipsoid or spindle shaped, brown, and measured 28 to 37 µm long × 13 to 18 µm wide (n = 50) with three false dissepiments. All characteristics were consistent with the morphology of Curvularia intermedia Boedijn (Sivanesan 1987). The rDNA internal transcribed spacer (ITS), glyceraldehyde-3-phosphate dehydrogenase (GPDH) and translation elongation factor (TEF) of a representative isolate (JSNJ-2019) were amplified using primers ITS1/ITS4, GPD1/GPD2 and EF1-983F/EF1-2218R (Manamgoda et al. 2014). The ITS sequence of JSNJ-2019 (GenBank: MZ613310) showed 99.83% (582/583bp) identity with C. intermedia (GenBank: MF370184 and GU073102); the GPDH sequence (GenBank: MZ701795) showed 99.66% (581/583bp) identity with C. intermedia (GenBank: LT715828) and the TEF sequence (Genbank: OM282974) showed 99.77% (864/866bp) identity with C. intermedia (GenBank: MF370186). Phylogenetic analysis based on the TEF sequences using Maximum-Likelihood and Bayesian methods placed JSNJ-2019 in the same clade with reference strain C. intermedia B19. The isolate was deposited in China Centre for Type Culture Collection (CCTCC) (Isolate code: CCTCC AF 2022041). For the pathogenicity assay, ten healthy M. vimineum plants grown in plastic pots (five to six leaf stage) were sprayed with 20ml conidial suspension (5×104 spores /ml); another ten healthy plants sprayed with sterile water served as controls. All inoculated and control plants were covered with transparent polyethylene bags immediately and were maintained in a greenhouse at 28±1℃. The transparent polyethylene bags were removed after 24 hours. The pathogenicity test was repeated three times. Five days post-inoculation, inoculated plants showed leaf blight symptoms as observed in the field, whereas no disease symptoms was observed on control plants. Reisolations were performed from inoculated plants, and the reisolated pathogen was confirmed as C. intermedia inter based on morphological and PCR assay (Konstantinova et al. 2002). No pathogens were isolated from control plants. Host range tests showed, C. intermedia JSNJ-2019 was pathogenic on corn, wheat, sorghum, barnyardgrass, crabgrass, green foxtail, Chinese sprangletop, cynodon, cogongrass, goosegrass, purslane and bedstraw and non-pathogenic on barley, rice, oat, cotton, bean, peanuts, rapeseed, tobacco and tea. These findings suggest C. intermedia could be used as a biocontrol agent against invasive M. vimineum and farmland weeds. However, application of C. intermedia as a bioherbicide should be limited to insensitive crop growing areas.

Digitized collections elucidate invasion history and patterns of awn polymorphism in Microstegium vimineum.

PremiseDigitized collections can help illuminate the mechanisms behind the establishment and spread of invasive plants. These databases provide a record of traits in space and time that allows for investigation of abiotic and biotic factors that influence invasive species.MethodsOver 1100 digitized herbarium records were examined to investigate the invasion history and trait variation of Microstegium vimineum. Presence–absence of awns was investigated to quantify geographic patterns of this polymorphic trait, which serves several functions in grasses, including diaspore burial and dispersal to germination sites. Floret traits were further quantified, and genomic analyses of contemporary samples were conducted to investigate the history of M. vimineum's introduction and spread into North America.ResultsHerbarium records revealed similar patterns of awn polymorphism in native and invaded ranges of M. vimineum, with awned forms predominating at higher latitudes and awnless forms at lower latitudes. Herbarium records and genomic data suggested initial introduction and spread of the awnless form in the southeastern United States, followed by a putative secondary invasion and spread of the awned form from eastern Pennsylvania. Awned forms have longer florets, and floret size varies significantly with latitude. There is evidence of a transition zone with short‐awned specimens at mid‐latitudes. Genomic analyses revealed two distinct clusters corresponding to awnless and awned forms, with evidence of admixture.ConclusionsOur results demonstrate the power of herbarium data to elucidate the invasion history of a problematic weed in North America and, together with genomic data, reveal a possible key trait in introduction success: presence or absence of an awn.

Woody plant secondary chemicals increase in response to abundant deer and arrival of invasive plants in suburban forests.

Plants in suburban forests of eastern North America face the dual stressors of high white‐tailed deer density and invasion by nonindigenous plants. Chronic deer herbivory combined with strong competition from invasive plants could alter a plant's stress‐ and defense‐related secondary chemistry, especially for long‐lived juvenile trees in the understory, but this has not been studied. We measured foliar total antioxidants, phenolics, and flavonoids in juveniles of two native trees, Fraxinus pennsylvanica (green ash) and Fagus grandifolia (American beech), growing in six forests in the suburban landscape of central New Jersey, USA. The trees grew in experimental plots subjected for 2.5 years to factorial treatments of deer access/exclosure × addition/no addition of the nonindigenous invasive grass Microstegium vimineum (Japanese stiltgrass). As other hypothesized drivers of plant secondary chemistry, we also measured nonstiltgrass herb layer cover, light levels, and water availability. Univariate mixed model analysis of the deer and stiltgrass effects and multivariate structural equation modeling (SEM) of all variables showed that both greater stiltgrass cover and greater deer pressure induced antioxidants, phenolics, and flavonoids, with some variation between species. Deer were generally the stronger factor, and stiltgrass effects were most apparent at high stiltgrass density. SEM also revealed that soil dryness directly increased the chemicals; deer had additional positive, but indirect, effects via influence on the soil; in beech photosynthetically active radiation (PAR) positively affected flavonoids; and herb layer cover had no effect. Juvenile trees’ chemical defense/stress responses to deer and invasive plants can be protective, but also could have a physiological cost, with negative consequences for recruitment to the canopy. Ecological implications for species and their communities will depend on costs and benefits of stress/defense chemistry in the specific environmental context, particularly with respect to invasive plant competitiveness, extent of invasion, local deer density, and deer browse preferences.

First Report of Leaf Spot Disease on Microstegium vimineum Caused by Bipolaris setariae in China.

First Report of Leaf Spot Disease on Microstegium vimineum Caused by Bipolaris setariae in China.

Digitized collections elucidate invasion history and patterns of awn polymorphism in Japanese stiltgrass (Microstegium vimineum)

Digitized collections elucidate invasion history and patterns of awn polymorphism in Japanese stiltgrass (Microstegium vimineum)

Digitized collections elucidate invasion history and patterns of awn polymorphism in Japanese stiltgrass (Microstegium vimineum)

Digitized collections elucidate invasion history and patterns of awn polymorphism in Japanese stiltgrass (Microstegium vimineum)

Invasive grass litter suppresses a native grass species and promotes disease

AbstractPlant litter can alter ecosystems and promote plant invasions by altering resource availability, depositing phytotoxins, and transmitting microorganisms to living plants. Transmission of microorganisms from invasive plant litter to live plants may gain importance as invasive plants, which often escape pathogens upon introduction to a new range, acquire new pathogens over time. It is unclear, however, if invasive plant litter affects native plant communities by promoting disease. Microstegium vimineum is an invasive grass that suppresses native populations, in part through litter production, and has acquired new fungal leaf spot diseases since its introduction to the United States. In a greenhouse experiment, we evaluated how M. vimineum litter and its pathogens mediated competition with the native grass Elymus virginicus. M. vimineum litter promoted disease on E. virginicus and suppressed establishment and biomass of both species. Litter had stronger negative effects on E. virginicus than M. vimineum, increasing the relative biomass of M. vimineum. Live plant competition reduced biomass of both species and live M. vimineum increased disease incidence on E. virginicus. Altogether, invasive grass litter suppressed both species, ultimately favoring the invasive species in competition, and increased disease incidence on the native species.

A fungal Bipolaris bicolor strain as a potential bioherbicide for goosegrass (Eleusine indica) control.

Tea, one of the most important commercial crops on earth, is strongly affected by weeds on productivity and quality. Bioherbicides are shedding new light on weed control in tea gardens in an economical and safe manner. A pathogenic strain SYNJC-2-2 was isolated from diseased leaves of a noxious weed, goosegrass (Eleusine indica), from a tea garden in Zhejiang Province, China. It was identified as the fungal species Bipolaris bicolor based on the morphological characteristics and phylogenetic analysis. The potential of the B. bicolor strain SYNJC-2-2 as a bioherbicide was assessed by determining its efficacy to control weeds and selectivity to crops, its infection process and the influence of environmental conditions on conidial production and germination. The ED90 (effective dose of conidia resulting in 90 disease index) of SYNJC-2-2 on goosegrass was 2 × 104 conidia mL-1 . Additionally, three Poaceae weeds, Setaria viridis, Microstegium vimineum and Pennisetum alopecuroides, were also extremely susceptible to SYNJC-2-2. SYNJC-2-2 was safe to 14 out of 17 crop species in nine families, especially tea plants. Conidial germination, hyphal growth and appressorial formation occurred within 3 to 6h on goosegrass leaves. Hyphae invaded leaf tissues mainly through epidermal cell junctions and cracks, causing cell death and necrotic lesions within 2 days on inoculated leaves and killing goosegrass plants within 7 days. Furthermore, SYNJC-2-2 has a strong adaptability to environmental variables and high conidial production capacity on goosegrass juice agar media. Bipolaris bicolor strain SYNJC-2-2 has the potential to be developed as a bioherbicide for controlling goosegrass, especially in tea gardens.

Nodding behavior observed in Japanese stiltgrass, Microstegium vimineum , seedlings from time-lapse observations

ABSTRACT Invasive species are the second main cause of biodiversity loss because of their exceptional ability to supplant native species by creating major upheavals in ecosystems. Inexpensive and prevalent time-lapse photography provides an exciting opportunity to better understand the aggressive behavior of invasive species including how they invade and conquer new territory. One of the most pervasive invasive species in the Eastern United States is Japanese stiltgrass, Microstegium vimineum (Trin.) A. Campus, which originated from Southeast Asia. Previous research has examined the conditions that enable Japanese stiltgrass to become invasive, but nothing is known regarding root and shoot behavior. Here time-lapse was used to examine Japanese stiltgrass seedlings, early in their development, as a first step to observe its behavior. Our results demonstrate that Japanese stiltgrass shoots appear to drop or collapse and then resurrect back to an upright stature – sometimes the same plant exhibits this behavior multiple times. We have shown, in addition, that emergent stilt root growth rate increases with increased root length. This and similar kinds of analyses may provide insight into how Japanese stiltgrass thrives aggressively in a non-native environment with the goal of developing better methods of controlling this noxious weed.

Academic‐conservation partnership reveals trade‐offs in treatment method and frequency needed to restore invaded floodplain

Invasive species disrupt native ecosystems by restructuring communities and altering ecosystem functions. To restore invaded plant communities, conservation practitioners eradicate invasive species, and re‐establish natives, but a lack of empirical understanding about how restoration methods and herbicide application frequencies affect native and invasive species limits restoration effectiveness. We developed a partnership between scientists and practitioners to evaluate conservation practices used to remove invasive stiltgrass Microstegium vimineum in an ongoing restoration of a Piedmont floodplain forest in Georgia, U.S.A. We examined the effects of the practitioners' existing large‐scale field application methods (herbicide, herbicide + native perennial seeding, herbicide + native perennial planting, and native perennial seeding) and frequencies (single, annual) using a smaller‐scale, controlled experiment. Both herbicide and planting native perennial seedlings reduced the invasive stiltgrass, but the methods varied in their optimal application frequency. Specifically, herbicide required annual application to maintain its potency, but planting natives was most effective following a single herbicide application. Our work highlights the benefits of planting native perennials as an effective alternative to herbicide in restoration plans. Furthermore, unlike the broad‐spectrum herbicide, native plantings did not reduce nearby non‐target taxa density. Our study illustrates trade‐offs in choosing restoration methods; although planting natives reduced the invasive species and provided associated benefits to the native community, this method took multiple growing seasons to establish and could require more up‐front costs than herbicide alone.

Abiotic factors, not mycorrhizal associations, predict size and abundance of the invasive grass Microstegium vimineum1

Both abiotic and biotic factors can influence distributions of invasive plant species, and it is important to understand how such factors contribute to invasion success in order to develop successful management strategies. Microstegium vimineum, known as stiltgrass, is an invasive annual grass in U.S. eastern deciduous forests that can outcompete native understory species, decrease diversity, and prevent the regeneration of native trees. Microstegium is also known to form associations with arbuscular mycorrhizal fungi (AMF), but research has yet to demonstrate whether this association has a role in Microstegium invasion and dominance over native vegetation. We conducted a field survey in invaded and uninvaded habitats across six sites near Louisville, KY, USA, to explore the relative importance of biotic versus abiotic factors in predicting Microstegium abundance and size. Canopy openness was the strongest predictor of Microstegium abundance, followed by soil moisture. Soil nitrogen was the strongest predictor of Microstegium tiller height. Surprisingly, AMF extraradical hyphal abundance and root colonization were not significant predictors of Microstegium abundance or size. In terms of abiotic factors, our results confirm previous studies that have demonstrated that Microstegium grows best in areas with high light and high soil moisture; however, our analysis provides further insight by assessing the relative importance of each of these factors for Microstegium invasion.

Chromosome Level Genome Assembly and Annotation of Highly Invasive Japanese Stiltgrass (Microstegium vimineum).

The invasive Japanese stiltgrass (Microstegium vimineum) affects a wide range of ecosystems and threatens biodiversity across the eastern USA. However, the mechanisms underlying rapid adaptation, plasticity, and epigenetics in the invasive range are largely unknown. We present a chromosome-level assembly for M. vimineum to investigate genome dynamics, evolution, adaptation, and the genomics of phenotypic plasticity. We generated a 1.12-Gb genome with scaffold N50 length of 53.44 Mb respectively, taking a de novo assembly approach that combined PacBio and Dovetail Genomics Omni-C sequencing. The assembly contains 23 pseudochromosomes, representing 99.96% of the genome. BUSCO assessment indicated that 80.3% of Poales gene groups are present in the assembly. The genome is predicted to contain 39,604 protein-coding genes, of which 26,288 are functionally annotated. Furthermore, 66.68% of the genome is repetitive, of which unclassified (35.63%) and long-terminal repeat (LTR) retrotransposons (26.90%) are predominant. Similar to other grasses, Gypsy (41.07%) and Copia (32%) are the most abundant LTR-retrotransposon families. The majority of LTR-retrotransposons are derived from a significant expansion in the past 1–2 Myr, suggesting the presence of relatively young LTR-retrotransposon lineages. We find corroborating evidence from Ks plots for a stiltgrass-specific duplication event, distinct from the more ancient grass-specific duplication event. The assembly and annotation of M. vimineum will serve as an essential genomic resource facilitating studies of the invasion process, the history and consequences of polyploidy in grasses, and provides a crucial tool for natural resource managers.

Invasive Plants Differentially Impact Forest Invertebrates, Providing Taxon-Specific Benefits by Enhancing Structural Complexity

Exotic plant species often negatively affect native herbivores due to the lack of palatability of the invading plant. Although often unsuitable as food, certain invasive species may provide non-nutritional ecological benefits through increased habitat structural complexity. To understand the potential for common invasive forest plant species of the eastern United States to benefit invertebrate communities, we examined the functional and taxonomic community composition of forest insects and spiders in long-term monitoring plots that contained invasive plant species. The extent of invasive plant species ground cover significantly altered spider community composition as categorized by hunting guild. Areas with higher invasive herbaceous and grass cover contained a higher abundance of space web-weaving and hunting spiders, respectively. Spider species richness and total invertebrate abundance also increased with greater invasive grass cover. Still, these trends were driven by just two invasive plant species, garlic mustard and Japanese stiltgrass, both of which have previously been shown to provide structural benefits to native invertebrate taxa. While these two species may improve the structural component of understory forest habitat, many invertebrate groups were not significantly correlated with other prevalent invasive plants and one species, mock strawberry, negatively affected the abundance of certain insect taxa. Particularly in forests with reduced native plant structure, invasive plant management must be conducted with consideration for holistic habitat quality, including both plant palatability and structure.

Evaluation of Bipolaris panici-miliacei as a bioherbicide against Microstegium vimineum

ABSTRACT Control of economically important gramineous weeds has been overly dependent on chemical herbicides resulting in herbicide resistance and pollution. The development of a biocontrol technique may be an optional approach to weed control. Bipolaris panici-miliacei strain SX5-2 was isolated from diseased Microstegium vimineum plants. Pathogenicity, host range test, culture and mass production, crop sensitivity, formulation development and field trials were conducted to evaluate the potential of this strain for a bioherbicide. Pathogenicity tests showed percent incidence was up to 90% at a conidial suspension concentration of 105 conidia/mL on M. vimineum under greenhouse conditions and more than 80% in the field. Host range tests on 57 species in 17 families determined that B. panici-miliacei strain SX5-2 was safe for rice, wheat, sorghum, soybean, cotton, vegetables, Zoysia japonica turf and most dicotyledonous plants. Only maize and sugar cane were severely infected. Pathogenicity bioassays showed that the strain could control those seven tested gramineous weeds Digitaria sanguinalis, Panicum virgatum, Echinochloa crus-galli, Microstegium japonicum, Microstegium nodosum, Sorghum sudanense and Leptochloa chinensis in the main dryland and paddy fields. Culture and mass-production studies revealed that combined submerged and solid fermentation with bran and sawdust was feasible for mass production of conidia. Therefore, based on virulent pathogenicity and feasible mass production, B. panici-miliacei may have a promising potential to be developed into a bioherbicide for biocontrol of grass weeds in most crops but not in susceptible maize or sugarcane.

Plant Species Composition and Interactions within Communities Invaded by Persicaria perfoliata (Polygonaceae)

Persicaria perfoliata (Mile-a-Minute Weed), an invasive vine, forms monocultural patches of various sizes within infested landscapes among patches also containing other plants. We compared the species composition of P. perfoliata-dominated patches and adjacent nondominated patches in 2 topographically homogeneous sites using 20 paired plots, nonmetric multidimensional scaling, multi-response permutation procedure, and indicator species analyses. Richness and diversity were lower in the P. perfoliata-dominated patches but both patch types had uncommon native plants present. The patch types differed significantly in composition, and the nondominated patches were dominated by another nonnative invader, Microstegium vimineum (Japanese Stiltgrass), or a native weed, Ambrosia artemisiifolia (Common Ragweed). Documenting potentially interacting native and exotic species within an invaded landscape will help predict likely restoration success in response to targeted nonnative-invasive plant removal.

Grass invasion reduces the resilience of tree regeneration to fire in the Central Hardwoods Region

Non-native grass invasions are altering fuels and fire behavior in forests, with uncertain consequences for tree regeneration and forest dynamics. We examined whether invasion by Microstegium vimineum, the most widespread invasive grass in the eastern United States, interacts with prescribed fire to reduce tree regeneration and evaluated how such interactions might influence long-term regeneration dynamics in the Central Hardwoods Region. Using paired invaded and uninvaded plots subjected to fall or spring burning, we quantified differences in pre-fire juvenile tree regeneration, fire intensity, and survival and resprouting rates of naturally established juvenile trees of varying sizes and species. Field data were then used to parameterize the Forest Vegetation Simulator (FVS), a forest growth and yield simulation model. Prior to burning, seedling density was 43% lower in invaded than uninvaded plots and the seedling size-class distribution skewed toward larger individuals, suggesting grass invasion and fire previously acted as a filter on small tree regeneration or that invasion occurred in areas with larger and fewer trees. Burning resulted in similar rates of fuel consumption among treatments, with 1-h, 10-h, and 100-h fuels decreasing an average of 23%, 42%, and 18.5% respectively. However, invaded plots exhibited lower flame lengths, shorter fire residence times, and smaller burned areas than uninvaded plots, indicating lower fire intensity. Despite experiencing lower fire intensity, invaded plots had 46% higher mortality of small trees (<3 mm stem diameter) and nearly 54% lower post-fire seedling persistence overall compared to uninvaded plots. Resprouting rate was positively related to seedling size and decreased marginally with invasion. Both a structural equation model and FVS simulations demonstrated that grass invasion had large, negative effects on seedling resprouting, regardless of fire intensity effects. Post-fire sapling persistence did not differ with invasion status. These results suggest that, while grass invasion can have varying effects on fire intensity, it consistently alters forest dynamics by reducing the resilience of tree regeneration to fire. Lengthening the time between prescribed fire applications in grass-invaded forests may be necessary to allow juvenile trees to reach an adequate size to survive burning.

CATHERINE MORRIS, Dept. of Natural Sciences and Mathematics, University of Charleston, Charleston, WV 25304, and MARK B. WATSON, Dept. of Natural Sciences and Mathematics, University of Charleston, Charleston, WV 25304. Impacts of Microstegium vimineum invasion on central West Virginia native plants.

Around the world natural ecosystems are being challenged and altered by invasive species. In particular, invasions of non-native grasses have a substantial impact on the population of native plant species. This study investigated the detrimental effects of an invasive grass, Japanese stiltgrass (Microstegium vimineum) on native plant species in central WV. M. vimineum is an emerging invasive species in the eastern United States. This stiltgrass is most abundant in highly disturbed areas such as trails and roadsides. Certain environmental conditions, forest feature, and soil conditions promote the growth and spread of the invasive grass. M. vimineum effects the soil and tree growth where it invades. While there is substantial information regarding the ecology and spread of M. vimineum, limited research has been done to determine the effects of the invasion on native plant communities. Study plots (30 plots (0.5m2)) were randomly selected in disturbed, moderately disturbed, and undisturbed locations. Canopy cover was measured at each location. The stems of M. vimineum counted and the native plant species were identified and quantified. The relationship between land disturbance and stem count was determined. Stem count of M. vimineum was highest in the moderately disturbed area with the lowest average native plant species richness. The second highest stem count was in the disturbed location which had the highest species richness but the lowest diversity. A negative correlation was found between stem count and species richness throughout all plots.

The vascular flora of Mettler's Woods, Somerset County, New Jersey

The objective of this study was to collect and identify the plant taxa at the 26 hectare Mettler's Woods during the 2010-2012 growing seasons. We identified 105 species, in 65 genera, and in 47 families. The largest families in the flora were the Poaceae (nine species), and the Cyperaceae (eight species). Carex was the largest genus in the flora with eight species. No rare taxa were observed at the study site. Non-native Microstegium vimineum now dominates the herbaceous understory. Additionally, the death of older trees has created gaps in the forest that has favored nonnative taxa such as Celastrus orbiculatus, Lonicera japonica, and Rosa multiflora.