Non-native Vascular Plant Research Articles

Species invasion and phylogenetic relatedness of vascular plants on the Qinghai-Tibet Plateau, the roof of the world

The Qinghai-Tibet Plateau (QTP) is the highest and one of the most extensive plateaus in the world. Investigating naturalized non-native plant species composition, phylogenetic relationships among naturalized plant species, and phylogenetic relationships between native and naturalized plant species on the plateau is of great importance. Here, we analyze a comprehensive dataset including all species of native and naturalized vascular plants known to occur in the core part of the QTP. We use net relatedness index (NRI) and nearest taxon index (NTI), which reflect deep and shallow evolutionary histories, respectively, to quantify phylogenetic relatedness among angiosperm species. The QTP included in this study (1,448,815 km2) has 9086 and 314 species of native and naturalized non-native vascular plants, respectively. We find that the naturalized angiosperm species are phylogenetically clustered with respect to the species pool including all native and naturalized angiosperm species on the QTP included in this study, regardless of whether NRI or NTI is used. For the eight regions within the QTP included in this study, NRI and NTI of naturalized angiosperms are positive in seven regions with respect to their respective regional species pools, reflecting phylogenetic clustering. Thus, naturalized angiosperm species are a phylogenetically clustered subset of all angiosperm species on the QTP, regardless of whether the studied plateau as a whole or its constituent regions are considered.

ArgVeg – Database of Central Argentina

The ArgVeg is a repository of vegetation-plots data registered in the Global Index of Vegetation Databases (GIVD ID: SA-AR-002). This report presents its main characteristics, potential uses, and future perspectives. In September 2022, the database contained 1092 vegetation-plot records, including 1184 valid native and non-native vascular plants. The database covers the main vegetation types of nine vegetation units of the Chaco, Espinal and Pampean phytogeographic provinces in central Argentina. Those types include native forests, shrublands, grasslands, halophytic vegetation and non-native woody communities present in either lowlands or mountain areas. This database represents a significant improvement in the availability of floristic information from subtropical and warm temperate areas in South America, which still represents a major knowledge gap worldwide. ArgVeg reflects the outstanding plant diversity of central Argentina and it is managed by the Plant Ecology and Phytogeography Group at the Multidisciplinary Institute of Plant Biology (Córdoba, Argentina). Not only the high biodiversity but also the complex landscape heterogeneity are the most important characteristics of the vegetation in this region. We hope to increase the number of plots in the near future and to strengthen regional and global networks to enhance the conservation and management of these endangered ecosystems.

Three Non-Native Vascular Plant Species New to the Flora of Alabama

Three species of non-native vascular plants are reported here as new to Alabama. Persicaria capitata (Buch.-Ham. ex D. Don) H. Gross, Pistacia chinensis Bunge, and Sedum diffusum S. Watson are all species cultivated as ornamentals, and likely represent escapes from nearby plantings. Recent collections of three non-native species in Alabama represent the first documented examples of these taxa as naturalized elements of the state's flora. In each case, the taxon was not included in the most recent statewide comprehensive publications including the Annotated Checklist of the Vascular Plants of Alabama (Kral et al. 2011) and the Alabama Plant Atlas (Keener et al. 2021). Additionally, Weakley (2020) did not include Alabama within the known distributions for each of them, and searches of BONAP (Kartesz 2020) and SERNEC (2021) failed to locate any additional non-cultivated specimens from Alabama.

New records in non-native vascular plants of Russian Lapland.

BackgroundThe non-native vascular plants of Murmansk Region (European Russia) are under active investigation towards the compilation of the first complete checklist. This work is part of the project 'Flora of Russian Lapland', which ultimately aims at the complete inventory of the taxonomy, distribution and status of vascular plant species in Murmansk Region, based on the comprehensive database of herbarium specimens, field observations and literature.New informationNew territory-level records of non-native vascular plants emerged during our inventory of herbarium collections and recent fieldwork. Fourteen species (Anthemisruthenica, Aruncusdioicus, Bromuscommutatus, Chaerophyllumhirsutum, Galegaorientalis, Geumaleppicum, Leonurusquinquelobatus, Lepidiumdensiflorum, Levisticumofficinale, Myrrhisodorata, Phleumphleoides, Prunusarmeniaca, Rorippasylvestris, Seneciovernalis) are reported as new to Murmansk Region. The historical occurrences of alien plants appeared in the territory largely as contaminants (of seed or forage). In particular, Rorippasylvestris and Seneciovernalis arrived with the forage imported during the Second World War. All recent occurrences originated by escape from confinement (ornamental purposes, horticulture, agriculture), reflecting a high diversity of the modern assortment of cultivated plants in commerce and private gardens. Regarding the invasion status, five alien species are considered casual and eight species are treated as locally established or persisting (for uncertain time). Only one species, Galegaorientalis, is considered naturalised and capable of further spreading in the territory, although without invasive potential.

EA Study of Non-native Vascular Plant Species at Hutcheson Memorial Forest Somerset County, New Jersey, USA

EA Study of Non-native Vascular Plant Species at Hutcheson Memorial Forest Somerset County, New Jersey, USA

A Floral Checklist for Wheaton Regional Park, Montgomery County, Maryland

Wheaton Regional Park is a suburban 500-acre park in Montgomery County, Maryland, on the northern edge of the Washington, D.C., metropolitan area. Early floristic surveys of the park, conducted between 1961–1964 when the park was founded, showed the park to be diverse, with 443 taxa of vascular plants. Our research team conducted a second round of floristic surveys between 2014–2019 to update the checklist of plants in the park. Here, we present a comprehensive checklist of all species collected in the park over the past 50 years, discuss recent plant introductions, and share a platform for a digital flora of the park through the Mid-Atlantic Megalopolis online portal. We documented 393 vascular plant species from the 1960s, as part of a comprehensive review of those collections. The 2010s collections recorded 293 vascular plant species, and an additional 16 species of bryophytes. In total, 554 species of plants (vascular and non-vascular) in 326 genera and 118 families have been recorded in Wheaton Regional Park over the past 50 years. We found that the surveys in the 2010s identified a substantial number of vascular plant species that were not recorded in the 1960s surveys. Additionally, we were able to recover less than half of the vascular plants recorded in the 1960s. The proportion of non-native vascular plant species increased from 22.1% in the 1960s to 34.5% in the 2010s. We offer recommendations for preserving the extant diversity of native plants in the park.

Noteworthy Collections of Four Non-native Vascular Plant Species New to the Flora of Alabama and One Species Rediscovered After 125 Years

Noteworthy Collections of Four Non-native Vascular Plant Species New to the Flora of Alabama and One Species Rediscovered After 125 Years

Non-native plant species in alder-dominated forests in Slovakia: what does the regional- and the local-scale approach bring?

Abstract European riparian forests are in general susceptible to plant invasions compared to other natural forest habitats. Their descriptive vegetation overviews with phytosociological affiliation contain detail insight into species composition patterns at various geographical scales, but quantitative assessment of the relationship between non-native plant richness and measured environmental variables is still scarce. We used two vegetation datasets of alder-dominated forests to analyse plant invasion patterns in the Pannonian and the Carpathian region of Slovakia. A large dataset of 918 vegetation plots was used at the regional scale, whereas 40 vegetation plots completed by ecological (mainly soil, climatic) predictors were used at the local scale in order to determine how they shape non-native species richness. We found significant differences (P < 0.05) between the Pannonian and the Carpathian region in the number of non-native vascular plants at both scales, with altitude being the most important predictor. Generalized Linear Models accounted for 56.6% and 59.6% of alien species richness data in the Pannonian and Carpathian region, respectively. Alien richness was affected by altitude and soil pH in the Pannonian region, but only by altitude in the Carpathian region.

Increasing status of non-native vascular plants in the Sefton Coast sand-dune system, north Merseyside, UK

Over 460 non-native (alien) taxa were recorded in a Sefton Coast sand-dune vascular plant inventory, their proportion in the flora increasing after 1999. Between 2005/06 and 2018, twice as many non-native as native plants were found. An analysis of occurrences of native and non-native taxa in six major habitat types found that a higher proportion of aliens was present in scrub/woodland and disturbed ground, while native plants had more occurrences in fixed dunes/dune grasslands, dune heath and wetlands. No differences between the two groups were detected for strandline/shingle and embryo/mobile dune habitats. Twenty-four non-native and 14 native taxa showed invasive characteristics in the duneland. The former included especially Hippophae rhamnoides and Rosa rugosa, both constituting major threats to sand-dune biodiversity. Particularly invasive native plants were Arrhenatherum elatius, Betula spp., Salix cinerea, and Ulex europaea. The main findings accord with studies elsewhere in Britain and Europe showing recent increases of neophytes in semi-natural habitats and that both non-native and native species can have invasive traits. The open habitats of coastal dunes seem to be particularly susceptible to plant invasions.

New records of non-native vascular plants in Gran Canaria (Spain, Canary Islands)

New records of non-native vascular plants in Gran Canaria (Spain, Canary Islands)

Non-native vascular flora of the Arctic: Taxonomic richness, distribution and pathways.

We present a comprehensive list of non-native vascular plants known from the Arctic, explore their geographic distribution, analyze the extent of naturalization and invasion among 23 subregions of the Arctic, and examine pathways of introductions. The presence of 341 non-native taxa in the Arctic was confirmed, of which 188 are naturalized in at least one of the 23 regions. A small number of taxa (11) are considered invasive; these plants are known from just three regions. In several Arctic regions there are no naturalized non-native taxa recorded and the majority of Arctic regions have a low number of naturalized taxa. Analyses of the non-native vascular plant flora identified two main biogeographic clusters within the Arctic: American and Asiatic. Among all pathways, seed contamination and transport by vehicles have contributed the most to non-native plant introduction in the Arctic.

Increasing impacts by Antarctica’s most widespread invasive plant species as result of direct competition with native vascular plants

Biological invasions represent significant economic and conservation challenges, though it is widely acknowledged that their impacts are often poorly documented and difficult to predict. In the Antarctic, one non-native vascular plant species is widespread and studies have shown negative impacts on native flora. Using field “common garden” experiments, we evaluate the competitive impact of the increasingly widespread invasive grass Poa annua on the only two native vascular species of Antarctica, the forb Colobanthus quitensis and the grass Deschampsia antarctica. We focus on interactions between these three plant species under current and a future, wetter, climate scenario, in terms of density of individuals. Our analysis demonstrates Poa annua has the potential to have negative impacts on the survival and growth of the native Antarctic vascular species. Under predicted future wetter conditions, C. quitensis communities will become more resistant to invasion, while those dominated by D. antarctica will become less resistant. Under a recently developed unified scheme for non-native species impacts, P. annua can be considered a species that can cause potentially moderate to major impacts in Antarctica. If current patterns of increased human pressure and regional climate change persist and mitigation action is not taken (i.e. reduction of propagule pressure and eradication or control measures), P. annua is likely to spread in Antarctica, especially in the Antarctic Peninsula region, with significant negative consequences for some of the most remote and pristine ecosystems worldwide. Tighter biosecurity across all operators in the region, improved surveillance for the species, and prompt, effective control actions will reduce these risks.

Nuevas citas de plantas vasculares alóctonas en Cataluña (NE de la península ibérica)

Aportamos citas de cinco plantas alóctonas nuevas para Europa —Commelina erecta, Cylindropuntia fulgida, Dasylirion serratifolium, xGraptosedum y Senecio crassissimus—, dos nuevas para la península ibérica —Lobelia laxiflora subsp. angustifolia y Pennisetum flaccidum— y cuatro nuevas para Cataluña —Dimorphotheca fruticosa, xGasteraloe beguinii, Opuntia elatior y Tradescantia sillamontana—. También presentamos nuevos datos sobre diez plantas poco citadas en Cataluña. En las últimas décadas el cultivo de plantas ornamentales constituye la principal causa de introducción de especies alóctonas a escala mundial, algunas de las cuales son potencialmente invasoras. La mayoría de las plantas que constan en este trabajo son escapadas de cultivos o provienen de vertidos de restos de jardinería. Algunas especies se encuentran localmente naturalizadas y en algún caso podrían presentar un comportamiento invasor.

Settlements as a source for the spread of non-native plants into Central European suburban forests

Urbanization is considered as a major driver for biotic homogenization. Urbanization also promotes the dispersal of non-native species. This study examined the roles of suburban settlements and of the surrounding landscape composition for the spread of non-native plant species into adjacent mixed deciduous forests in Southern and Northwestern Switzerland. The number and abundance of native and non-native vascular plant species in both the ground vegetation and shrub layer were recorded in 15 forest sites situated adjacent to settlements and 15 control sites far from settlements. Various site and landscape characteristics were assessed in the surroundings (100 m radius) of the study sites. In both regions we found a higher number and larger abundance of non-native plant species in forest sites adjacent to settlements than in control forest sites. Furthermore, non-native plants were more frequently recorded close to roads and in sites surrounded by a large percentage cover of garden. All these effects were more pronounced in Southern Switzerland, a region with milder winter climate, than in Northwestern Switzerland. Our study showed that settlements are a source for the spread of non-native plant species into Central European suburban forests, and that the composition of the surrounding landscape matrix (e.g. traffic infrastructure, percentage cover of gardens) also affects the establishment of non-native plants.

Square-stalked St. John’s-wort, <i>Hypericum tetrapterum</i>, in Peel Region, Ontario: a New Non-native Vascular Plant Species for Eastern North America

The Eurasian Square-stalked St. John’s-wort (Hypericum tetrapterum Fr.: Hypericaceae) was found growing in an open Eastern White Cedar (Thuja occidentalis L.) swamp in Caledon, Regional Municipality of Peel, Ontario. This is the first record for eastern North America; previous North American occurrences have been on the Pacific coast in Vancouver, British Columbia, Canada (1991), and in Wahkiakum County, Washington State, USA (2003).

Non-native species in the vascular flora of the national park «Samarsky Bir»

Results of non-native flora surveys on Samara Dniprovska River valley within the designed National Park «Samarsky Bir» were analyzed in the paper. Scientific justification on first stage creation of the national-level National Park «Samarsky Bir» was prepared in 2012. Its area included the main park area with floodplain, arena and gully landscapes of the rivers Samara and Oril interstream. List of vascular plant species on floodplain, arena and gully habitats of Prisamar'ya counted 887 species. They are classified as 5 divisions, 6 classes, 108 families, 429 genera. This article presents a list of non-native flora fraction with bioecological characteristic of the plant species. The surveys were conducted by conventional methods on vascular flora studying. Analysis of the main plant ecomorphs was carried out by A. L. Belgard ecomorph system (1950). Invasion of plant species in the steppe zone of Ukraine has a long history complicated by significant anthropogenic transformation of the territory. We investigated the status of non-native plants, their ecomorphs, and tendency to invasiveness on the territory of National Park «Samarsky Bir» designed. Presence of 195 adventitious vascular plant species belonging to 48 families was determined. Of them, 7 families with the greatest abundance of non-native species contained 113 taxa (58 % of the total); 20 families were represented with 2–7 advents, and 20 families contained only 1 non-native species. Thus, today the share of non-native species in the vascular flora of the region accounted for nearly 22 %. Most of adventitious species are mesoxerophytes and xeromesophytes. In a cenomorphic relationship, vegetation being ruderal on the territory of Ukraine is dominated in composition of non-native flora. Within the total number of adventitious species, archaeophytes amount up 44 %, whereas neophytes come up to 56 %. The greatest abundance of adventitious species has been found in Brassicaceae, Asterasea and Poaceae families (15 %, 12 %, and 11 % of the total, respectively). 119 non-native vascular plant species were found in the steppe cenoses, 79 species in the gully and watershed forests, 90 species in floodplain forests, and 52 species on the territory of the sandy terrace. Among all the non-native species, 28 species have been identified as invasive, and there was a trend to increased invasiveness of some species in recent years. Among heterogenous species 12 of them were identified as invasive, and there was a tendency to increase theinvasiveness of some species in recent years. The analysis provided on non-native flora in the National Park evidences significant anthropogenic transformation of the territory; that requires establishment of appropriate regime on protection of this important ecological object.

Non-native species in the vascular flora of highlands and mountains of Iceland.

The highlands and mountains of Iceland are one of the largest remaining wilderness areas in Europe. This study aimed to provide comprehensive and up-to-date data on non-native plant species in these areas and to answer the following questions: (1) How many non-native vascular plant species inhabit highland and mountainous environments in Iceland? (2) Do temporal trends in the immigration of alien species to Iceland differ between highland and lowland areas? (3) Does the incidence of alien species in the disturbed and undisturbed areas within Icelandic highlands differ? (4) Does the spread of non-native species in Iceland proceed from lowlands to highlands? and (5) Can we detect hot-spots in the distribution of non-native taxa within the highlands? Overall, 16 non-native vascular plant species were detected, including 11 casuals and 5 naturalized taxa (1 invasive). Results showed that temporal trends in alien species immigration to highland and lowland areas are similar, but it is clear that the process of colonization of highland areas is still in its initial phase. Non-native plants tended to occur close to man-made infrastructure and buildings including huts, shelters, roads etc. Analysis of spatio-temporal patterns showed that the spread within highland areas is a second step in non-native plant colonization in Iceland. Several statically significant hot spots of alien plant occurrences were identified using the Getis-Ord Gi* statistic and these were linked to human disturbance. This research suggests that human-mediated dispersal is the main driving force increasing the risk of invasion in Iceland’s highlands and mountain areas.

New records of interesting xenophytes in the Iberian Peninsula. V

As a continuation of previous research on the naturalization of non-native vascular plants in the Iberian Peninsula new chorological data are presented for 16 xenophytes recorded between 2010 and 2014, mostly in the provinces of Huelva and Barcelona (Spain) and in the Algarve and Estremadura (Portugal). For each taxon details about distribution, habitats occupied, previous records, degree of naturalization, etc. are provided. Lachenalia bulbifera and Cyperus albostriatus are probably reported for the first time in the wild in Europe, as are Gamochaeta filaginea , and Dysphania anthelmintica and Oenothera lindheimeri for Portugal and Spain respectively. Cosmos bipinnatus is cited as a novelty for the Algarve (Portugal). Newly reported or confirmed for the province of Huelva are: Amaranthus hypochondriacus, Epilobium brachycarpum, Nephrolepis cordifolia, Ficus microcarpa, Tamarix parviflora and Tamarix ramosissima , while Atriplex semibaccata , Chloris truncata , and Elymus elongatus subsp. ponticus are new for Barcelona . Finally, Passiflora caerulea is a novelty for both Barcelona and Huelva provinces.

New distributional records of non-native vascular plants in northern Italy

New distributional records of non-native vascular plants are provided for the Italian regions Piemonte, Lombardia and Emilia-Romagna. <em>Panicum</em> <em>barbipulvinatum</em> is reported for the first time from Italy.

Climate, trees, pests, and weeds: Change, uncertainty, and biotic stressors in eastern U.S. national park forests

The US National Park Service (NPS) manages over 8900km2 of forest area in the eastern United States where climate change and nonnative species are altering forest structure, composition, and processes. Understanding potential forest change in response to climate, differences in habitat projections among models (uncertainty), and nonnative biotic stressors (tree pests and diseases and invasive plants) are vital for forward-looking land management. In this research, we examined potential changes in tree habitat suitability using two climate scenarios (‘least change’ and ‘major change’) to evaluate uncertainty in the magnitude of potential forest change. We further used nonnative tree pest and plant data to examine strengths and spatial patterns of these stressors and their correlations with projected changes in tree habitat. Analyses included 121national parks, 134tree species (from the US Forest Service Climate Change Atlas), 81 nonnative tree pests (from the US Forest Service Alien Forest Pest Explorer Database), and nonnative vascular plant presence data from each park. Lastly, for individual tree species in individual parks, we categorized potential habitat suitability change (from late 20th century baseline to 2100) into three change classes: large decrease (<50%), minor change (50–200%), and large increase (>200%). Results show that the potential magnitude of forest change (percentage of modeled tree species in the large decrease and large increase classes, combined) varies from 22% to 77% at individual parks. Uncertainty (the percentage of tree species in differing change classes across climate scenarios) varies from 18% to 84% at parks. Nonnative plant species comprise from <10% to about 50% of the flora at parks. The number of nonnative tree pest species ranges from 15 to 70 among parks. Potential forest change, uncertainty, and nonnative pests and plants have significant positive correlations, illustrating the broad scope of potential compounding effects and future changes in many eastern forests. The combination of rapid climate change and nonnative stressors may accelerate decline of some tree species and inhibit other species from occupying climatically suitable habitat. Stewarding forests for continuous change is a challenge for park managers. Understanding and anticipating projected rates and directions of forest change and nonnative biotic stressors should facilitate monitoring and management efforts on park lands and across the broader landscape.