Arable Weeds Research Articles

Reintroduction strategies for rare arable weeds in agricultural practice and their influence on yield

AbstractAgricultural intensification and changing landscape structure led to decreasing numbers of arable flora and fauna during the last decades. To counteract these declines, arable plant diversity needs to be restored. It is important to promote regional plant communities including endangered species to ensure adaption to agricultural landscapes. Therefore, this study examines the development of arable plant diversity, crop yield and the reintroduction success of rare arable plants (RAPs) under different practical farming strategies in cereals from 2019 to 2021 in southwestern Germany. Farming strategies varied regarding weed control intensity (none, mechanical, herbicide with and without efficiency gap), fertilisation (mineral and none) and row spacing (12.5 cm and 20 cm). Additionally, two different seed mixtures containing RAP and common species were used for reintroduction: one commercially available and another self‐composed. Reintroduction success was quite high with more than 80% establishment rate. Species numbers doubled in all treatments over time, except the one with herbicide application, with on average 8–10 species emerging from the soil seed bank. Reintroduction of RAP increased arable plant species richness further up to 37 species. The site‐adapted mixture showed in the end a site‐typical weed community. Yield was significantly lower in treatments with reintroduction via sown mixtures and no weed control, losing on average 65% yield. The reintroduction of RAP was successful and accompanied by an increasing floral diversity, however, with a simultaneous yield loss. Financial incentives or subsidies are therefore still necessary to compensate yield loss for reintroduction and conservation efforts.

Quantifying the impacts of management and herbicide resistance on regional plant population dynamics in the face of missing data

Abstract A key challenge in the management of populations is to quantify the impact of interventions in the face of environmental and phenotypic variability. However, accurate estimation of the effects of management and environment, in large‐scale ecological research is often limited by the expense of data collection, the inherent trade‐off between quality and quantity, and missing data. In this paper we develop a novel modelling framework, and demographically informed imputation scheme, to comprehensively account for the uncertainty generated by missing population, management, and herbicide resistance data. Using this framework and a large dataset (178 sites over 3 years) on the densities of a destructive arable weed (Alopecurus myosuroides) we investigate the effects of environment, management, and evolved herbicide resistance, on weed population dynamics. In this study we quantify the marginal effects of a suite of common management practices, including cropping, cultivation, and herbicide pressure, and evolved herbicide resistance, on weed population dynamics. Using this framework, we provide the first empirically backed demonstration that herbicide resistance is a key driver of population dynamics in arable weeds at regional scales. Whilst cultivation type had minimal impact on weed density, crop rotation, and earlier cultivation and drill dates consistently reduced infestation severity. Synthesis and applications: As we demonstrate that high herbicide resistance levels can produce extremely severe weed infestations, monitoring herbicide resistance is a priority for farmers across Western Europe. Furthermore, developing non‐chemical control methods is essential to control current weed populations, and prevent further resistance evolution. We recommend that planning interventions that centre on crop rotation and incorporate spring sewing and cultivation to provide the best reductions in weed densities. More generally, by directly accounting for missing data our framework permits the analysis of management practices with data that would otherwise be severely compromised.

Seeing the fields through the weeds: introducing the WeedEco R package for comparing past and present arable farming systems using functional weed ecology

The functional ecology of arable weeds provides a way of comparing present-day and past farming regimes. This paper presents the R package WeedEco, an open-source resource which allows users to compare their archaeobotanical dataset against three previously published arable weed models to understand fertility, disturbance or a combination of both. The package provides functions for data organisation, classification and visualisation, allowing users to enter raw archaeobotanical data, obtain trait values from the functional trait dataset, conduct discriminant analysis and plot the results against the relevant present-day model. Using data from the early medieval site of Stafford in the UK, the paper provides a detailed example of the use of the package, demonstrating its different functions, as well as how the results can be interpreted.

Major field margin vegetation types in France and their relationships with climate, agricultural landscapes and management intensity

ABSTRACT Arable field margins are an important semi-natural habitat providing multiple functions in agroecosystems. Despite three decades of research, analyses of species assemblage and functional traits are lacking. Leveraging a national monitoring network in metropolitan France, we aim to provide a comprehensive taxonomic and functional synthesis of field margin flora, outline main field margin types and explore their associations with management practices, climate, and agricultural landscapes. We analysed data from 532 field margins surveyed between 2013 and 2017, using both uni- and multivariate analyses. Field margins exhibited great diversity with 711 distinct taxa (12% of all flora in mainland France) at the national scale and an average of 16 species per 10 m2 locally. While field margins contained few species of conservation value, they offered a refuge for many declining species as well as rare arable weed species. We identified seven main field margin types, each linked to distinct conditions of climate, soil, landscape and agricultural practices. Mediterranean field margins notably differed from all others. In the main cluster, vineyard margins also stood out as distinct from annual crop margins. Additionally, field margins in landscapes with a high proportion of grassland differed from those within intensively cultivated field crop plains in conventional agriculture. Overall, our study highlights the high botanical diversity of field margins and their interest for plant conservation in agricultural landscapes. Promoting the installation and/or maintenance of field margins through agri-environmental schemes should thus favour biodiversity conservation and associated ecosystem provision.

Vegetation survey methodology in arable weeds is reported with less detail from vegetation science than weed science

Vegetation survey methodology in arable weeds is reported with less detail from vegetation science than weed science

Roman to early medieval cereal farming in the Rhineland: weeds, tillage, and the spread of the mouldboard plough

ABSTRACT A new model for gauging levels of soil disturbance (i.e. tillage) by analysing arable weed assemblages from archaeological contexts is applied to an extensive Roman-to-early medieval archaeobotanical sequence from the region west of Cologne. It tests the hypothesis that increasing use of the mouldboard plough, especially in a three-field system, would result in increased levels of soil disturbance which would be reflected in the kinds of weeds that grew in arable fields. The results point to clear differences in tillage regimes during the Roman period, providing support for the view that military sites were not provisioned by the same networks that supplied the civilian market. They also reveal generally low disturbance levels for the fifth and sixth centuries, indicating a continuing predominance of ard cultivation in the post-Roman period. The majority of seventh- to eighth-century samples had, however, been grown in ‘high disturbance’ conditions, a pattern that continued through the eighth and ninth centuries. Although use of the mouldboard plough within a fully developed three-field system may not have become widespread until the tenth or eleventh century, our evidence suggests that a plough capable of turning over the soil was in use in the Rhineland at a much earlier date.

Seed germination of common and endangered arable weed species is differently affected by the herbicide metazachlor and its transformation products

AbstractHigh inputs of herbicides have caused the decline of arable weed species, which formerly evolved under less intensively managed crop lands. Arable weed species have adapted their germination strategies to respond to unfavourable periods. However, species considered endangered have more specific germination requirements. The herbicide metazachlor (MZ), in its formulated form Butisan®, is used for the control of annual and dicotyledonous weeds and degrades in the soil into two major transformation products (TPs): metazachlor oxalic acid (MZ‐OA) and metazachlor ethane sulphonic acid (MZ‐ESA). These TPs are often found in higher concentrations compared to MZ. We tested the effect of MZ and its TP on seed germination of four common and three endangered arable weed species present in Central Europe by setting up multi‐factorial climate chamber experimental designs. We chose concentrations imitating field conditions and according to previously reported fraction occurrences in the topsoil. We assessed germination by measuring germination percentage, mean germination time and synchrony of germination. All germination variables were affected with increasing concentrations of MZ. Both, common and endangered species showed a decrease in germination percentage under the highest concentration of MZ. MZ and MZ‐OA increased the synchronicity of endangered species, while both TPs decreased mean germination time of endangered species. Common species showed less significant differences when compared to the control and also had a less synchronised and longer germination time compared to endangered species. The observed response of common species to both MZ and TPs may be convenient in the face of short term unfavourable environmental conditions, such as those found in intensively managed arable lands. Our results highlight that the species‐specific response of arable weeds to herbicides will further increase the dominance of common over rare arable weed species.

Incidence of thermophilic, grass and rare arable weeds in cereal fields in the Czech and Slovak Republic

Our objectives were to characterise arable weeds of the Czech and Slovak Republic in cereals, especially considering important groups of species: thermophilic, weedy grasses, and rare and endangered species. The three-year phytocoenological survey was conducted from 2006 to 2008 in five climatic regions and eight different soil types. 379 relevĂŠs were recorded, and 281 weed species were found. The effects of both the climatic region and soil type were found to be statistically significant. Species richness increased with altitude. Several species were distinctly associated with soil type, from fertile chernozems to less fertile cambisols, while fluvisols were strongly associated with e.g. Calystegia sepium (L.) R. Br. The incidence of species outside their expected regions generally fit two categories: the most pervasive weeds found almost in all climate regions, such as Echinochloa crus-galli (L.) P. Beauv., or rare weeds in higher altitudes than expected, such as Lolium temulentum L. Rare and endangered species were more likely to be found in a colder climate and poorer soils, and this is linked to less intensive management; however, not all endangered arable species can tolerate such conditions. Even though this data is not recently collected, this is still valuable information on the distribution of weedy species, especially concerning the current interest in maintaining biodiversity.

Assessment of ACC and P450 Genes Expression in Wild Oat (Avena ludoviciana) in Different Tissues Under Herbicide Application.

Target-site resistance (TSR) and non-target-site resistance (NTSR) to herbicides in arable weeds are increasing rapidly all over the world and threatening universal food safety. Resistance to herbicides that inhibit ACCase activity has been identified in wild oat. In this study, expression of ACC1, ACC2, CYP71R4 and CYP81B1 genes under herbicide stress conditions were studied in two TSR (resistant in the residue Ile1781-Leu and Ile2041-Asn of ACCase) biotypes, two NTSR biotypes and one susceptible biotype of A. ludoviciana for the first time. Treated and untreated biotypes with ACCase-inhibitor clodinafop propargyl herbicide were sampled from the stem and leaf tissues at 24h after treatment. Our results showed an increase in gene expression levels in different tissues of both types of resistance biotypes that occurred under herbicide treatment compared with non-herbicide treatment. In all samples, the expression levels of leaf tissue in all studied genes were higher than in stem tissue. The results of ACC gene expression showed that the expression level of ACC1 was significantly higher than that of ACC2. Also, expression levels of TSR biotypes were higher than NTSR biotypes for the ACC1 gene. For both CYP71R4 and CYP81B1 genes, the expression ratio increased significantly in TSR and NTSR biotypes in different tissues after herbicide treatment. In contrast, the expression levels of CYP genes in NTSR biotypes were higher than in TSR biotypes. Our results support the hypothesis that the reaction of plants to herbicide is carried out through a different regulation of genes, which can be the result of the interaction of resistance type in the target or non-target-site.

청동기시대 북부 비옥한 초승달 지대 초기 도시체제의 농업경영과 전략

The aim of the current study is to analyse major crop and arable weed plant material from three archaeological sites, Tell Mohammed ‘Arab, Tell Brak and Alalakh in order to investigate crop husbandry and agricultural strategies across the northern Fertile Crescent in especially the Late Bronze Age of the second millennium BC. The existing models require agricultural output to increase substantially over a period of several thousand years. With some recent exceptions, how this was achieved, whether by increasing the area of land under cultivation (extensification) or the amount produced per unit of land, by increasing inputs in terms of soil working, water and/or fertiliser (intensification), has not been established to any reasonable extent based on the remains of crop production themselves. The new data on crop spectra and associated arable weed taxa is analysed using weed functional ecology and crop stable isotope analysis, which provide direct evidence of crop growing conditions and consequently the nature of land management practices. The reconstruction of ancient crop husbandry practices drawn from weed functional ecology and crop stable isotope results demonstrates that contemporary farmers endeavoured to promote agricultural output by increasing the unit of land under cultivation rather than by increasing the amount produced per area of land, inputs in terms of soil working or water and/or fertiliser. The archaeobotanical assemblages provide a certain diversity of cropping strategies and relatively extensive/low-intensity regimes, depending especially on settlement scale. Overall, a strong correlation is observed among these different dimensions of agricultural activity, urbanisation cycles and environmental settings.

Undersowing oats with clovers supports pollinators and suppresses arable weeds without reducing yields

Abstract Sustainable food production requires agriculture to conserve biodiversity and facilitate ecosystem services to maintain productivity levels while reducing inputs detrimental to ecosystem functioning. Increasing within‐field vegetation diversity by legume intercropping seems promising to facilitate cropping system multi‐functionality. Effects of intercropping with legumes on biodiversity‐mediated ecosystem services such as pollination or natural pest control are, however, not sufficiently understood. Using 26 observation plots in a paired field design, we studied the effects of undersowing oats with a mixture of three annual clovers across different aspects of cropping system multi‐functionality. We investigated 16 below‐ and above‐ground ecosystem service indicators related to soil mineral nitrogen, arable weed control, pollination, disease and pest pressures, natural pest control and crop yield. We found lower arable weed cover, higher flower cover and pollinator densities as well as decreased root‐feeding nematode densities in intercropped observation plots compared with the non‐intercropped controls. However, intercropping decreased spider activity densities and oat yield nitrogen content. Root diseases, pest damages, natural pest control and crop yield were not affected by intercropping. The biomass of undersown clovers was positively related with the differences in flower cover and pollinator densities, and negatively related with the differences in arable weed cover between the intercropped and the control treatment. Synthesis and applications: We demonstrate that undersowing annual clovers suppresses arable weeds and simultaneously support pollinators without reducing crop yields or taking land out of arable production. Undersown plant mixtures should, however, be tailored to support a wider spectrum of pollinators and benefit natural pest control to support a higher level of overall cropping system multi‐functionality.

Characterisation of Czech arable weed communities according to management and production area considering the prevalence of herbicide‐resistant species

AbstractHerbicide resistance is a widespread issue that impacts management of conventional farms, but also has ramifications for the weed community assembly; it is therefore important to see how these species factor into the weed community assembly of farms throughout the countryside. This research analysed species richness and community diversity in 98 field relevés from 48 organic and 50 conventional farms evenly distributed between two major production regions of the Czech Republic and then evaluated the incidence of species which have been reported resistant in the Czech Republic and its neighbouring countries. Farms were selected independently of any acknowledged resistant species. Out of 164 species found in this survey, only eight species have had herbicide‐resistant biotypes reported in the Czech Republic, while a total of 19 species had herbicide‐resistant biotypes reported in neighbouring countries. Species with recorded resistance to PSII inhibitors in the Czech Republic tended to be found together and were mostly associated with the beet production region, characterised by low altitude: Amaranthus retroflexus, Chenopodium album, Echinochloa crus‐galli and Solanum nigrum. Species with reported resistance to ALS and ACCase‐inhibiting herbicides were not clearly associated with a particular region or farming type. Of the species which have had reported herbicide resistance in the neighbouring countries, several were found in conventional fields within the growing season and we recommend immediate screening for herbicide resistance in these species and more diligent action in management according to anti‐resistance strategies: Bromus sterilis resistant to ACCase‐inhibiting herbicides, A. retroflexus resistant to ALS‐inhibiting herbicides or Avena fatua resistant to ACCase and ALS‐inhibiting herbicides. This work is unique in that it is evaluating weed species diversity in organic and conventional farms and using the context to frame the prevalence of high‐risk herbicide‐resistant species; thereby putting the potential incidence of herbicide resistance into perspective at the landscape level.

Iconic Arable Weeds: The Significance of Corn Poppy (Papaver rhoeas), Cornflower (Centaurea cyanus), and Field Larkspur (Delphinium consolida) in Hungarian Ethnobotanical and Cultural Heritage

There are an increasing number of initiatives that recognize arable weed species as an important component of agricultural biodiversity. Such initiatives often focus on declining species that were once abundant and are still well known, but the ethnographic relevance of such species receives little recognition. We carried out an extensive literature review on the medicinal, ornamental, and cultural applications of three selected species, Papaver rhoeas, Centaurea cyanus, and Delphinium consolida, in the relevant Hungarian literature published between 1578 and 2021. We found a great diversity of medicinal usages. While P. rhoeas stands out with its sedative influence, D. consolida was mainly employed to stop bleeding, and C. cyanus was most frequently used to cure eye inflammation. The buds of P. rhoeas were sporadically eaten and its petals were used as a food dye. All species fulfilled ornamental purposes, either as garden plants or gathered in the wild for bouquets. They were essential elements of harvest festivals and religious festivities, particularly in Corpus Christi processions. P. rhoeas was also a part of several children's games. These wildflowers were regularly depicted in traditional Hungarian folk art. In poetry, P. rhoeas was used as a symbol of burning love or impermanence; C. cyanus was frequently associated with tenderness and faithfulness; while D. consolida regularly emerged as a nostalgic remembrance of the disappearing rural lifestyle. These plants were also used as patriotic symbols in illustrations for faithfulness, loyalty, or homesickness. Our results highlight the deep and prevalent embeddedness of the three iconic weed species studied in the folk culture of the Carpathian Basin. The ethnobotanical and cultural embeddedness of arable weed species should also be considered when efforts and instruments for the conservation of arable weed communities are designed.

The utility of the 'Arable Weeds and Management in Europe' database: Challenges and opportunities of combining weed survey data at a European scale.

Over the last 30 years, many studies have surveyed weed vegetation on arable land. The 'Arable Weeds and Management in Europe' (AWME) database is a collection of 36 of these surveys and the associated management data. Here, we review the challenges associated with combining disparate datasets and explore some of the opportunities for future research that present themselves thanks to the AWME database. We present three case studies repeating previously published national scale analyses with data from a larger spatial extent. The case studies, originally done in France, Germany and the UK, explore various aspects of weed ecology (community composition, management and environmental effects and within-field distributions) and use a range of statistical techniques (canonical correspondence analysis, redundancy analysis and generalised linear mixed models) to demonstrate the utility and versatility of the AWME database. We demonstrate that (i) the standardisation of abundance data to a common measure, before the analysis of the combined dataset, has little impact on the outcome of the analyses, (ii) the increased extent of environmental or management gradients allows for greater confidence in conclusions and (iii) the main conclusions of analyses done at different spatial scales remain consistent. These case studies demonstrate the utility of a Europe-wide weed survey database, for clarifying or extending results obtained from studies at smaller scales. This Europe-wide data collection offers many more opportunities for analysis that could not be addressed in smaller datasets; including questions about the effects of climate change, macro-ecological and biogeographical issues related to weed diversity as well as the dominance or rarity of specific weeds in Europe.

Infected grasses as inoculum for Fusarium infestation and mycotoxin accumulation in wheat with and without irrigation

Grasses growing next to agricultural fields influence the Fusarium abundance, the species composition, and the mycotoxin accumulation of wheat plants, especially the field parts directly adjacent to grasses, are highly affected. Grasses are a more attractive and suitable habitat for Fusarium fungi compared to other arable weeds and occur at mostly every semi-natural landscape element (e.g., kettle holes, hedgerows, field-to-field-borders). In our study, we analyzed the ability of a highly Fusarium infected grass stripe (F. graminearum, F. culmorum, F. sporotrichioides) to infect an adjacent wheat field with these species. Results show that the primary inoculated Fusarium species were as well the dominant species isolated from the wheat field. Regarding transects originating from the grass stripe going into the field, the results demonstrate that wheat ears next to the infected grass stripe have a higher Fusarium abundance and furthermore show higher mycotoxin accumulation in the wheat kernels. This effect was highly promoted by irrigation. Therefore, grass stripes next to arable fields must be considered as reservoirs for fungal infections and as a source for a contamination with mycotoxins.

Enhancing weed multifunctionality at a landscape scale: A simulation study

There is a pressing need for research guiding the design and management of multifunctional landscapes that combine the delivery of production services and that of other ecosystem services. Arable weeds are an interesting model as they can impact negatively crop production but also contribute to maintain pollination and pest control services. Here, we assessed weed multifunctionality using weed data recorded within a small landscape, in the field edge and field core of 97 fields over six consecutive years. We detected a general positive correlation between harmfulness and services provision, at the field-scale and at the landscape scale. At the field scale, the flora of field edges strongly contributed to the delivery of (dis)services; some fields delivered interesting trade-offs, and this was only weakly explained by the crop management strategy. At the landscape scale, we explored through scenarii the impact of changes in the composition (proportional cover of the different crop management strategies) and structure (field size, i.e. length of field edges) of the land-use mosaics on weed multifunctionality. Land–use mosaics offering interesting trade-offs were for the most part characterised by an even representation of the different crop management strategies. Small-grained landscapes did not offer better trade–offs than the current landscape structure, but slightly improved the inter-annual stability of services. Our results support the idea that promoting the co-existence of various cropping strategies within landscape is a good option to reconcile the positive and negative impacts of weeds.

Archaeobotanical Remains from Tel Gezer, Israel, and their Implications for the ‘Threshing Floors’ of Field VI

ABSTRACT Alternating laminae of charred ash and packed earth uncovered in Field VI of Tel Gezer, Israel, have been interpreted as the remains of Iron Age threshing floors. Recent geoarchaeological research has, however, led to the reinterpretation of similar deposits elsewhere as the remains of a trash heap. This paper presents the results of analysis and dating of charred plant remains that were recovered from the laminated deposit of Gezer Field VI and reassesses their implications for the origins of the strata. A broad spectrum of potentially cultivated crops and arable weeds are identified, matching contemporary archaeobotanical assemblages elsewhere in the region. The archaeobotanical remains are found to be inconsistent with the residues expected to derive from a threshing floor. Rather, they appear to derive from a range of depositional pathways. This is consistent with a context into which numerous sources of plant remains were deposited, such as a midden. Evidence for the potential use of this space as a multi-purpose activity area will be a focus of future research. The dating of the archaeobotanical remains also aligns with a recently developed radiocarbon-based chronology to suggest that the laminated deposit is dated several centuries earlier than previously thought.

Arable Weeds at the Edges of Kettle Holes as Overwintering Habitat for Phytopathogenic Fungi

Weeds in agricultural landscapes can serve as alternate hosts for phytopathogenic fungi and promote the spatial and long-term distribution of these fungi. Especially, semi-natural habitats such as kettle holes are considered as a source of fungal pathogens because they are a permanent habitat for various weed species in arable lands. In our study, we investigated the suitability of nine different weed species and families at the edges of 18 kettle holes in two consecutive autumn/winter seasons as alternate hosts for Fusarium and Alternaria. We detected a fungal infestation with both genera on every weed species investigated with significantly higher abundances of these fungi in the second, notably wetter season. Eight weed species were described as non-host plants for Fusarium and Alternaria in agricultural landscapes in Brandenburg, Germany for the first time. In both autumn/winter periods, weeds harbored more Alternaria than Fusarium. The study revealed a high Fusarium species diversity in weeds and a community structure of up to 12 Fusarium species at the edges of kettle holes. Grasses showed the highest diversity and often the highest fungal abundances compared to herbaceous plants. Therefore, these habitats in arable lands can act as ecosystem disservice and promote the spread of fungal diseases in the surrounding crop fields.

Cytochrome P450 CYP709C56 metabolizing mesosulfuron-methyl confers herbicide resistance in Alopecurus aequalis.

Multiple herbicide resistance in diverse weed species endowed by enhanced herbicide detoxification or degradation is rapidly growing into a great threat to herbicide sustainability and global food safety. Although metabolic resistance is frequently documented in the economically damaging arable weed species shortawn foxtail (Alopecurus aequalis Sobol.), relevant molecular knowledge has been lacking. Previously, we identified a field population of A. aequalis (R) that had evolved metabolic resistance to the commonly used acetolactate synthase (ALS)-inhibiting herbicide mesosulfuron-methyl. RNA sequencing was used to discover potential herbicide metabolism-related genes, and four cytochrome P450s (CYP709C56, CYP71R18, CYP94C117, and CYP94E14) were identified with higher expressions in the R vs. susceptible (S) plants. Here the full-length P450 complementary DNA transcripts were each cloned with identical sequences between the S and R plants. Transgenic Arabidopsis overexpressing CYP709C56 became resistant to the sulfonylurea herbicide mesosulfuron-methyl and the triazolo-pyrimidine herbicide pyroxsulam. This resistance profile generally but does not completely in accordance with what is evident in the R A. aequalis. Transgenic lines exhibited enhanced capacity for detoxifying mesosulfuron-methyl into O-demethylated metabolite, which is in line with the detection of O-demethylated herbicide metabolite in vitro in transformed yeast. Structural modeling predicted that mesosulfuron-methyl binds to CYP709C56 involving amino acid residues Thr-328, Thr-500, Asn-129, Gln-392, Phe-238, and Phe-242 for achieving O-demethylation. Constitutive expression of CYP709C56 was highly correlated with the metabolic mesosulfuron-methyl resistance in A. aequalis. These results indicate that CYP709C56 degrades mesosulfuron-methyl and its up-regulated expression in A. aequalis confers resistance to mesosulfuron-methyl.

Assessment of weed invasion at bait sites in a Central European lower montane zone

The effects of wild game feeding on the local environment have been widely investigated in northern European countries but have received little consideration in Central Europe. Bait sites, that is, places where food is set out to entice wild boar for hunting are becoming ever more widespread, and they are having an increasing impact on surrounding vegetation. The aim of the present study was to assess the extent of weed invasion at different bait types. 3 bait sites located in forests, 3 baits in clearings and 3 baits on unpaved forest roads in the Central European lower montane zone, in Hungary. The field work was conducted in May and August. Four transects were laid out (at right angles to each other) from the centre of each bait, and consisted of 22 one meter square quadrats, in which vegetation survey were conducted. The application of multivariate statistical methods (PCA) and UPGMA analysis to the data collected revealed substantial differences between the bait types. The baits in the forest were the least degraded, with a sparse understory cover in both surveys. Road baits displayed a notable difference, as they varied depending on canopy closure, accessibility and exposure. Sites in clearings proved to be the most infected. Furthermore, there was a significant difference between the vegetation of the periods examined, arable weeds dominated in August. A stress gradient was detected along the transects, with the proportion of weeds decreasing from the centre, while the natural components of the vegetation increased. The effect was more noticeable in clearings, probably due to their greater openness. Invasion is typically limited to the immediate environment of the bait sites, but valuable patches of habitat can also be destroyed, and bait sites may serve as bridgeheads for biological invasions.