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Full-Text Articles in Weed Science
Soil Characteristics Drive Ficaria Verna Abundance And Reproductive Output, Justin P. Kermack, Emily Rauschert
Soil Characteristics Drive Ficaria Verna Abundance And Reproductive Output, Justin P. Kermack, Emily Rauschert
Biological, Geological, and Environmental Faculty Publications
Lesser celandine (Ficaria verna Huds.), an invasive plant from Europe, is becoming widespread in river valleys throughout the northeastern United States and the Pacific Northwest. Its high rate of asexual bulbil and tuber production creates dense infestations threatening native spring ephemerals. Ficaria verna abundance and reproductive output (seeds, bulbils, and tubers) were examined in invaded transects spanning a disturbance gradient away from a river. Site characteristics (photosynthetically active radiation [PAR], soil pH, moisture, texture, and nutrients) were quantified to examine their roles in plant abundance and reproduction. A larger-scale study examined random transects not specifically chosen based on F. …
Plant Community Associations Of Two Invasive Thistles, Emily S.J. Rauschert, Katriona Shea, Sarah Goslee
Plant Community Associations Of Two Invasive Thistles, Emily S.J. Rauschert, Katriona Shea, Sarah Goslee
Biological, Geological, and Environmental Faculty Publications
In order to combat the growing problems associated with biological invasions, many researchers have focused on identifying which communities are most vulnerable to invasion by exotic species. However, once established, invasive species can significantly change the composition of the communities that they invade. The first step to disentangling the direction of causality is to discern whether a relationship with other vegetation exists at all. Carduus nutans and C. acanthoides are similar invasive thistles, which have caused substantial economic damage worldwide. We assessed the associations between the thistles and the standing flora in four sites in central Pennsylvania in which they …
Influence Of Microsite Disturbance On The Establishment Of Two Congeneric Invasive Thistles, Emily S.J. Rauschert, Katriona Shea
Influence Of Microsite Disturbance On The Establishment Of Two Congeneric Invasive Thistles, Emily S.J. Rauschert, Katriona Shea
Biological, Geological, and Environmental Faculty Publications
The successful establishment of invasive species has been shown to depend on aspects of the invaded community, such as gap characteristics. Biotic resistance may be particularly critical for stopping invaders at early life history stages, but new species can often invade following disturbances, which may create microsites with very different characteristics than are usually present. We examine the response of two invasive thistle species, Carduus nutans L. and C. acanthoides L., to three different microsite characteristics: disturbance type, size, and water availability. The two species initially responded differently to the type of disturbance: C. acanthoides had higher emergence and survival …
Invasional Interference Due To Similar Inter- And Intraspecific Competition Between Invaders May Affect Management, Emily S.J. Rauschert, Katriona Shea
Invasional Interference Due To Similar Inter- And Intraspecific Competition Between Invaders May Affect Management, Emily S.J. Rauschert, Katriona Shea
Biological, Geological, and Environmental Faculty Publications
As the number of biological invasions increases, the potential for invader– invader interactions also rises. The effect of multiple invaders can be superadditive (invasional meltdown), additive, or subadditive (invasional interference); which of these situations occurs has critical implications for prioritization of management efforts. Carduus nutans and C. acanthoides, two congeneric invasive weeds, have a striking, segregated distribution in central Pennsylvania, USA. Possible hypotheses for this pattern include invasion history and chance, direct competition, or negative interactions mediated by other species, such as shared pollinators. To explore the role of resource competition in generating this pattern, we conducted three related experiments …
Coexistence Patterns Of Two Invasive Thistle Species, Carduus Nutans And C. Acanthoides, At Three Spatial Scales, Emily S.J. Rauschert, Katriona Shea, Ottar N. Bjørnstad
Coexistence Patterns Of Two Invasive Thistle Species, Carduus Nutans And C. Acanthoides, At Three Spatial Scales, Emily S.J. Rauschert, Katriona Shea, Ottar N. Bjørnstad
Biological, Geological, and Environmental Faculty Publications
To better understand the competitive processes involved in invasion by congeners, we examine coexistence patterns of two invasive species, Carduus nutans and C. acanthoides, at three spatial scales. A roadside survey of 5 × 5 km blocks in a previously identified overlap zone provided information about the regional scale. At smaller scales, we surveyed four fields of natural co-occurrence, quantifying the spatial patterns at the field scale by randomly placed 1 × 1 m quadrats and at the smallest scale by detailing plant position within the quadrats. The patterns observed are strikingly different at the different scales. At the regional …
Japanese Stiltgrass: An Invasive Plant On The Move, Emily S.J. Rauschert, Andrea N. Nord
Japanese Stiltgrass: An Invasive Plant On The Move, Emily S.J. Rauschert, Andrea N. Nord
Biological, Geological, and Environmental Faculty Publications
No abstract provided.
Slow Spread Of The Aggressive Invader, Microstegium Vimineum (Japanese Stiltgrass), Emily S.J. Rauschert, David A. Mortensen, Ottar N. Bjørnstad, Andrea N. Nord, Nora Peskin
Slow Spread Of The Aggressive Invader, Microstegium Vimineum (Japanese Stiltgrass), Emily S.J. Rauschert, David A. Mortensen, Ottar N. Bjørnstad, Andrea N. Nord, Nora Peskin
Biological, Geological, and Environmental Faculty Publications
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 …