Microstegium vimineum (Japanese Stiltgrass) Research

Pulang ---> Microstegium vimineum --> Research

Competition

Jordan M. Marshall, David S. Buckley, and Jennifer A. Franklin "Competitive interaction between Microstegium vimineum and first-year seedlings of three central hardwoods," The Journal of the Torrey Botanical Society 136(3), 342-349, (1 July 2009). https://doi.org/10.3159/09-RA-006.1

We established an experiment designed to compare effects of Microstegium vimineum (Japanese stiltgrass) on seedlings of three native hardwood species to investigate the hypothesis that competitive effects of M. vimineum on juvenile trees will vary across different tree species. Growth and survival of Acer rubrum, Liriodendron tulipifera, and Quercus rubra first-year seedlings were compared in plots with and without M. vimineum in three planting beds under 50 percent shade. The tree species studied are abundant and of particular interest in the Central Hardwood Region. A. rubrum and L. tulipifera seedlings experienced reduced growth in several foliar characteristics in the presence of M. vimineum. Q. rubra did not exhibit any differences in foliar characteristics between plots with and without M. vimineum, however there was a reduction in Q. rubra stem weight as a result of the presence of M. vimineum. The differential responses of A. rubrum, L. tulipifera, and Q. rubra to the presence of M. vimineum observed in this study support the hypothesis that effects of this exotic species will vary across tree species. As a result of reductions in the growth of A. rubrum and L. tulipifera, the presence of M. vimineum in forest understories may reduce the rate at which seedlings of these species are recruited into larger size classes.

Janet A. Morrison, Heather A. Lubchansky, Kerry E. Mauck, Kelly-Marie McCartney, and Brian Dunn "Ecological comparison of two co-invasive species in eastern deciduous forests: Alliaria petiolata and Microstegium vimineum," The Journal of the Torrey Botanical Society 134(1), 1-17, (1 January 2007). https://doi.org/10.3159/1095-5674(2007)134[1:ECOTCS]2.0.CO;2

Many communities invaded by one non-native plant species also are invaded by others due to a shared response to environmental factors that promote invasive species generally, such as fragmentation, disturbance, and proximity to seed sources. Direct comparison of these co-invasive species in their shared communities therefore is necessary for understanding the ecology of invaded communities, particularly if management resources must be prioritized. We compared ecological characteristics of two of the most important co-invasive herb layer species in forests of the eastern United States, Alliaria petiolata (garlic mustard, a C3 biennial herb native to Europe) and Microstegium vimineum (Japanese stilt-grass, a C4 annual grass native to east Asia). Both are invasive across a wide geographic range, establish dense stands under varying canopy covers, and are associated with lower native herb layer diversity and abundance. However, A. petiolata has attracted much greater attention from the scientific and management communities. Our research had three related components aimed at understanding which species may be a greater threat. We conducted a greenhouse experiment with shaded and unshaded growing conditions, in which M. vimineum grew much greater shoot biomass (although total biomass was similar) and photosynthesis rates for M. vimineum generally exceeded those for A. petiolata. We also did a large field experiment using transplants grown from seed. Microstegium vimineum had greater survivorship, less insect herbivory, larger mass, and higher photosynthesis rates than first-year A. petiolata. In addition, we studied a co-invaded natural community. Both species' percent cover were variable across the site but had no relationship to photosynthetically active radiation (PAR) levels. Microstegium vimineum had higher cover in 2001 and by 2005 had increased dramatically over A. petiolata in co-invaded plots. In the summer months M. vimineum had greater photosynthesis rates (measured in situ with a Li-Cor 6400) and were matched only by A. petiolata's early spring rates. These results indicate that in forests where they co-invade M. vimineum may have greater potential for spread than A. petiolata and deserves increased attention from both scientists and forest managers.

Christopher M. Oswalt, Sonja N. Oswalt, Wayne K. Clatterbuck, Effects of Microstegium Vimineum (Trin.) A. Camus on native woody species density and diversity in a productive mixed-hardwood forest in Tennessee, Forest Ecology and Management, Volume 242, Issues 2–3, 2007, Pages 727-732, https://doi.org/10.1016/j.foreco.2007.02.008.

We investigated the impacts of Microstegium vimineum (Trin.) A. Camus, on the density and diversity of native woody species regeneration following canopy disturbance in a productive mixed-hardwood forest in southwest Tennessee. Field observations of M. vimineum in the forest understory pre- and post-canopy disturbance led us to believe the species might have an impact on post-disturbance regeneration. Specifically, we noticed what appeared to be a dramatic increase in post-disturbance M. vimineum which we hypothesized would compete with native woody species regeneration, negatively impacting species diversity and seedling density. Total native woody species stems per hectare declined with increasing M. vimineum cover (P < 0.001, r2 = 0.80). Simple species richness of native woody species and Shannon's and Simpson's diversity indecies also decreased with increasing M. vimineum percent cover (P = 0.0023, r2 = 0.47, P = 0.002, r2 = 0.47 and P = 0.02, r2 = 0.31, respectively). Our results indicate that M. vimineum, may have a negative impact on native woody species regeneration in southern forests.

Ecology

Landsman, A., Burghardt, K. T., and Bowman, J. Invasive grass (Microstegium vimineum) indirectly benefits spider community by subsidizing available prey. Ecology and Evolution. https://doi.org/10.1002/ece3.6752

Invasive plant species cause a suite of direct, negative ecological impacts, but subsequent, indirect effects are more complex and difficult to detect. Where identified, indirect effects to other taxa can be wide-ranging and include ecological benefits in certain habitats or locations.

Here, we simultaneously examine the direct and indirect effects of a common, invasive grass species (Microstegium vimineum) on the invertebrate communities of understory deciduous forests in the eastern United States. To do this, we use two complementary analytic approaches to compare invaded and reference plots: (a) community composition analysis of understory arthropod taxa and (b) analysis of isotopic carbon and nitrogen ratios of a representative predatory spider species.

Invaded plots contained a significantly greater abundance of nearly all taxa, including predators, herbivores, and detritivores. Spider communities contained over seven times more individuals and exhibited greater species diversity and richness in invaded plots.

Surprisingly, however, the abundant invertebrate community is not nutritionally supported by the invasive plant, despite 100% ground cover of M. vimineum. Instead, spider isotopic carbon ratios showed that the invertebrate prey community found within invaded plots was deriving energy from the plant tissue of C3 plants and not the prevalent, aboveground M. vimineum.

Synthesis and applications. We demonstrate that invasive M. vimineum can create non-nutritional ecological benefits for some invertebrate taxa, with potential impacts to the nutritional dynamics of invertebrate–vertebrate food webs. These positive impacts, however, may be restricted to habitats that experience high levels of ungulate herbivory or reduced vegetative structural complexity. Our results highlight the importance of fully understanding taxon- and habitat-specific effects of invading plant species when prioritizing invasive species removal or management efforts.

Rauschert, E.S.J., Mortensen, D.A., Bjørnstad, O.N. et al. Slow spread of the aggressive invader, Microstegium vimineum (Japanese stiltgrass). Biol Invasions 12, 563–579 (2010). https://doi.org/10.1007/s10530-009-9463-y

Microstegium vimineum (Japanese stiltgrass) is a non-native weed whose rapid invasion threatens native diversity and regeneration in forests. Using data from a 4 year experiment tracking new invasions in different habitats, we developed a spatial model of patch growth, using maximum likelihood techniques to estimate dispersal and population growth parameters. The patches expanded surprisingly slowly: in the final year, the majority of new seedlings were still within 1 m of the original patch. The influence of habitat was not as strong as anticipated, although patches created in roadside and wet meadow habitats tended to expand more rapidly and had greater reproductive ratios. The long-term projections of the patch growth model suggest much slower spread than has typically been observed for M. vimineum. The small scale of natural dispersal suggests that human-mediated dispersal, likely influenced by forest road management, is responsible for the rapid spread of this invasive species.

Summaries and Reviews

Penulis: A. Sunjian