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Biol Invasions (2019) 21:861–873

https://doi.org/10.1007/s10530-018-1866-1 (0123456789().,-volV)(0123456789().,-volV)

ORIGINAL PAPER

A global assessment of terrestrial alien ferns (Polypodiophyta): species’ traits as drivers of naturalisation and invasion

Emily J. Jones . Tineke Kraaij . Herve Fritz . Desika Moodley

Received: 3 June 2018 / Accepted: 13 October 2018 / Published online: 27 October 2018 Ó Springer Nature Switzerland AG 2018

Abstract The global threat posed by invasive alien determine which traits influence the probability that plants has prompted inventory compilations and a terrestrial alien fern will become naturalised or screening exercises that aim to understand invasive- invasive. Generalised linear models with transition ness in various taxa. Various traits influence the stages as response variables, were used to assess the invasiveness of a species but do not apply to all plant effects of various anthropogenic, biological and taxa. Ferns are rare or absent from such inventories, distributional traits on invasiveness. Our model but notable fern invasions do exist. We developed a explained 30–40% of the variance associated with global inventory of terrestrial alien true ferns (Poly- invasiveness and showed that a ground-dwelling life podiophyta) comprising 157 species, using published form, reproductive plasticity, tolerance for distur- literature and online inventories. We aimed to bance and varied light conditions, and a broad introduced range (interpreted as high environmental tolerance and popularity in horticulture) were impor- Electronic supplementary material The online version of this article (https://doi.org/10.1007/s10530-018-1866-1) con- tant determinants of invasiveness in alien ferns. We tains supplementary material, which is available to authorized highlighted which geographic regions and fern users.

E. J. Jones (&) Á T. Kraaij Á H. Fritz D. Moodley School of Natural Resource Management, Nelson Department of Invasion Ecology, Institute of Botany, Mandela University, Madiba Dr, George Central, Academy of Sciences of the Czech Republic, George 6530, South Africa 252 43 Pru˚honice, Czech Republic e-mail: [email protected] e-mail: [email protected] T. Kraaij e-mail: [email protected] H. Fritz e-mail: [email protected]

E. J. Jones Invasive Species Programme, South African National Biodiversity Institute, Cape Town, South Africa

H. Fritz CNRS, UCBL, UMR 5558, Universite´ Lyon, 69622 Villeurbanne, France

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862 E. J. Jones et al. families had the highest incidences of alien ferns and Councils’ (FLEPPC) list of category 1 invasive plant identified particular species of concern. This study species (i.e. ‘‘invasive exotics that are altering native aids in the understanding of the mechanisms under- plant communities by displacing native species, lying invasiveness in alien ferns and the findings can changing community structures or ecological func- inform future research on this understudied taxon as tions, or hybridizing with natives’’), alien ferns invasive species. comprise 12.5% of the list (FLEPPC 2017). In Florida the rapid invasion of Lygodium microphyllum (Cav.) Keywords Alien ferns Á Global inventory Á Invasion R. Br. has infested more than 40,000 ha of unique stage Á Introduced range Á Native range Á Reproductive indigenous habitat (Goolsby 2004). The plant is able to plasticity survive in low-light conditions, and its rapid spread is facilitated by year-round vegetative growth (high propagule pressure) and spore production (Volin et al. 2004; Robinson et al. 2010). Introduction Various anthropogenic factors and environmental and biological traits have shown to be useful predic- Invasive alien species are one of the greatest threats to tors of species invasiveness (Kolar and Lodge 2001; biodiversity, ecosystems and ecosystem services Van Kleunen et al. 2010; Richardson and Pysˇek 2012; (Millennium Ecosystem Assessment 2005). Species Moodley et al. 2016; Miller et al. 2017). Traits such as invasion generally follows a sequence of transitions mode of reproduction, dispersal strategy, plant height, (termed the ‘introduction-naturalisation-invasion con- growth rate, and environmental tolerance may provide tinuum’; Richardson et al. 2000) from introduction alien plants with a competitive advantage over native (i.e. species introduced into an environment outside of species thereby facilitating invasion (Kolar and Lodge its native range) to naturalisation (i.e. establishment of 2001). In addition, certain environmental factors (such self-sustaining populations) to invasion (i.e. the ability as habitat and climate suitability, lack of competition to expand its range beyond the initial site of infesta- (including predation), and presence of anthropogenic tion/colonisation) (Falk-Petersen et al. 2006; Black- disturbance) may render an area susceptible to inva- burn et al. 2011). The global significance of invasive sion (Terazano et al. 2018). Propagule pressure and species has prompted inventory compilations and suitability for horticulture have been found to be screening exercises as a means to provide information important determinants of invasion success (Carlton about the mechanisms of invasion and inform sustain- 2003; Dehnen-Schmutz et al. 2007) and relate to able management strategies, transforming the study of introduction efforts by humans exceeding a plants’ invasion biology into a predictive science (Latombe natural dispersal capabilities. These effects, combined et al. 2017;Pysˇek et al. 2017). Global inventories of with longer residence times (time since first introduc- alien and invasive biota are generally more compre- tion) usually correlate with the increased likelihood of hensive for faunal species (Pysˇek et al. 2017) than for plants becoming naturalised or invasive and having floral species. Inventories on alien flora are generally larger areas of occupancy (Wilson et al. 2007; Van poor in species composition and are restricted in terms Kleunen et al. 2010). There are site and invasion-stage of geographical scale (Latombe et al. 2017). dependent effects that influence the success of natu- Ferns in particular, are rare or absent from inven- ralisation or invasion in alien plants (Pysˇek et al. tories on alien flora for many parts of the world. In a 2012), and traits associated with invasiveness do not recent global inventory of naturalised vascular plants, necessarily apply to all plant taxa (Dawson et al. 2009; ferns were absent from the list which comprised 200 of Moodley et al. 2016). the most widely distributed naturalised plant taxa of The majority of studies assessing invasive traits in the world (Pysˇek et al. 2017). However, in a few alien plants focus on angiosperms (Kolar and Lodge regions alien ferns rank amongst some of the most 2001) but few studies have considered alien ferns even conspicuous, ecologically damaging, and well-studied though their traits arguably present a plant taxon with invasive species (Pemberton et al. 2002; Wilson 2002; high invasive potential (Robinson et al. 2010). Ferns Lott et al. 2003; Murakami et al. 2007; Chau et al. differ most notably from angiosperms in terms of their 2013). For instance, of the Florida Exotic Pest Plant reproductive systems by having two free-living 123 Author's personal copy

A global assessment of terrestrial alien ferns (Polypodiophyta) 863 generations namely gametophytes and sporophytes et al. 2004), and anthropogenic influences (de Winter (de Groot et al. 2012). They reproduce by means of and Amoroso 2003). intergametophytic mating and recombination, or by Ferns hold little economic value, therefore cultiva- sustaining homozygosity through intragametophytic tion for purposes other than horticulture is unlikely (de selfing (i.e. self-fertilization of a single gametophyte) Winter and Amaroso 2003). Since the early 1800s (Lloyd 1974). Intragametophytic selfing is an impor- humans have moved hundreds of species of ferns out tant characteristic to consider with regards to invasive of their natural ranges for horticultural purposes potential in ferns because self-fertilization has been (Lowe 1864). Despite this it is estimated that globally shown to be aligned with long distance colonization only ca. 60 species of ferns are problematic because of (Stebbins 1957). Spores are able to tolerate unfavour- their invasiveness (Robinson et al. 2010). Given their able aerial conditions and once established, sporo- diversity, wide-ranging distribution and long horticul- phytes display a high tolerance of varying soil nutrient tural history, ferns are a key taxon requiring system- levels and have the ability to photosynthesise under atic screening for invasiveness and assessment of traits low light conditions. Less than 1% of fern sporophytes associated with invasiveness. Our objectives were exhibit desiccation tolerance with fewer genera therefore to (1) develop a global inventory of terres- (Notholaena, Cheilanthes and Asplenium) showing trial (non-aquatic) alien true ferns (Polypodiophyta; gametophyte revival after desiccation or dormancy Christenhusz and Chase 2014; hereafter ‘alien ferns’) (Page 2002; Watkins et al. 2007). Ferns furthermore using literature and online inventories; (2) determine pose resistance to predation, pathogens, and fungal the invasion status of each species; (3) determine attack through photochemical armament but benefit which traits (i.e. including. ecological, biological and from plant associations through the exploitation of anthropogenic) influence the probability that a terres- mycorrhizae (Richardson and Walker 2010). Various trial alien fern will become naturalised or invasive, ecological and reproductive characteristics thus aid in and (4) highlight problematic species and families to the successful establishment of ferns in a wide range of inform future risk assessments. habitats (Lott et al. 2003), and despite their evident invasive capabilities, ferns are often overlooked as invasive taxa. Methods Ferns have a long evolutionary history and are diverse with approximately 9500 known species of Inventory, geographic distribution, and family terrestrial Polypodiophyta (Christenhusz and Chase representation 2014; The Plant List 2013). They inhabit a variety of environments but fern diversity in terms of numbers of In order to develop a global inventory of (terrestrial) species, genera, and families, is generally greater in alien ferns we surveyed various available sources regions with a higher evapotranspiration potential, which included: published literature; herbarium annual precipitation and topographic complexity records; alien and invasive plant lists e.g. FLEPPC (Kessler 2010). Up to ca. 60% of ferns are found in (http://www.fleppc.org) and Southern African Plaint the wet tropics, and in wet mountainous areas ferns Invaders Atlas (SAPIA); and local, regional or global can represent up to 13% of the local flora (de Winter online inventories (e.g. Atlas of living Australia and Amoroso 2003). In contrast, ferns are virtually (www.ala.org.au), Calflora (www.calflora.org), Cen- absent in arid zones (with the exception of a few tre for invasive species and ecosystem health (www. specifically adapted genera, e.g. Cheilanthes sp.) and invasive.org), Delivering Alien Invasive Species are species poor in areas with Mediterranean type Inventories for Europe (www.europe-aliens.org), and climates (Ferrer-Casta´n and Vetaas 2005). Although the Global Invasive Species Database (www.iucngisd. species distribution and richness may be influenced by org). Searches were prompted using key terms such as environmental factors such as climate, topography and ‘‘pteridophyte’’ OR ‘‘ferns’’ AND ‘‘alien’’ OR ‘‘inva- soil, fern occurrence and abundance may also be sive’’ OR ‘‘adventive’’ OR ‘‘naturalised’’ OR ‘‘non- largely influenced by the dispersal ability of a species native’’. Synonyms among records in our inventory (de Groot et al. 2012), source-sink effects (Leibold were removed and only species recognised (or

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864 E. J. Jones et al. considered ‘unresolved’) by The Plant List (www. explanatory variables, Table 1) are associated with theplantlist.org) were retained. invasion status (i.e. response variables; hereafter Species invasion status terminology has often been referred to as ‘status’). The modelled logistic function loosely applied in the invasion literature (Blackburn predicts the probability of changing status for a given et al. 2011). Therefore, to ensure consistency, we set of traits. Since the relative importance of traits evaluated the accuracy and potentially modified the affecting invasiveness differs amongst the stages of status of each species according the criteria of Falk- invasion (Richardson and Pysˇek 2012), we estimated Peterson et al. (2006) and Blackburn et al. (2011). Not the status change from (1) introduced to naturalised all records supplied comprehensive and current infor- (transition one), (2) naturalised to invasive (transition mation, hence, some species’ status differ from that two), or (3) introduced to invasive (transition three), specified by the source. For each species we recorded with each transition coded as a binary response information about mode of introduction but found that variable. The first transition along the introduction- horticulture was the purpose for all introduced species, naturalisation-invasion continuum (Richardson et al. hence we ignored this variable in further analysis. We 2000) could not be assessed as all native (i.e. non- recorded the kingdom(s) and floristic region(s) from alien) ferns could not be considered in this study given which a species was donated, and floristic region(s) to the size of the taxon. Instead we included transition which it was introduced (kingdoms and regions follow three (introduced to invasive) in order to augment the Takhtajan 1986). size of the dataset for analysis of traits contributing to To gain an understanding of the geographic distri- invasiveness. bution of alien ferns, we assessed the frequency Prior to running the GLMs, we tested for collinear- distribution of alien species in terms of their native ity between explanatory variables using Pearson’s floristic regions and introduced floristic regions. We correlation coefficient (Supplementary 2). We used also collected information on several ecological and r = 0.6 as the cut-off point to jointly include variables biological attributes (Table 1) for each species using in a model (Tabachnick and Fidell 1996). Number of scientific literature, online databases, field identifica- native regions and number of native kingdoms were tion guides, compendiums, and open source websites highly correlated. We first included number of native (Supplementary 1). In similar studies it is common regions (and not number of native kingdoms) in our practice to control for phylogenetic constraints models as it has often been a significant predictor in (Grotkopp and Rejma´nek 2007; Moodley et al. 2016; similar studies (Moodley et al. 2013, 2016). However, Pysˇek and Richardson 2008). However, phylogenetic number of native regions never contributed signifi- relationships among existing and fossil ferns remain cantly, hence we rather retained number of native largely unresolved (Hennequin et al. 2017; Wolf et al. kingdoms. 1998) and is further constrained by the lack of We used the output of the analysis of variance information surrounding primitive or advanced char- (ANOVA) to re-order the variables and relationships acter states (Roux 2001). To assess the prevalence of within the models from most significant to least alien fern species in relation to family size we significant. A manual backwards stepwise selection calculated for each family the proportion of the total procedure was used to gradually remove the non- number of accepted species in that family (according significant (P [ 0.05) variables, starting with the to The Plant List 2013) that have been introduced interaction terms. Variables and significant interac- outside their native range. To assess whether alien tions were kept in the model even if they showed species are overrepresented in certain families we then nonsignificant single effects. In such models, the order compared the proportion of each family that is alien to of the explanatory variables can have consequences on the proportion that is alien for terrestrial Polypodio- the remaining deviance explained by subsequent phyta as a whole (9500 species; The Plant List 2013). variables, hence their significance. Therefore, building several models and reordering variables enables robust Analysis of traits influencing invasiveness conclusions. This also enabled us to test for the effect of variables that could be masked by partial correlation We used generalised linear models (GLMs) with (i.e. weak collinearity). Furthermore, other studies binomial response variables to assess which traits (i.e. have shown that, building hierarchical models allows 123 Author's personal copy

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Table 1 Explanatory variables and interactions considered in the assessment of traits potentially associated with invasiveness in terrestrial alien ferns Trait Variable No. of Explanation type modalities

Mode of regeneration Categorical 2 (1) Adopts both methods of reproduction (vegetative and sexual)/(0) only adopts one method (vegetative or sexual) Life form Categorical 2 (1) Ground-dwellers (soil substrate, including geophytes, cryptophytes and hemicryptophytes)/(0) epiphytic (arboreal substrate) or lithophytic (rock or stone substrate) Growth form Categorical 2 (1) Rhizomal/(0) arborescent (e.g. tree fern) Wet habitat Categorical 2 (1) Preference for wet habitats (wetlands, streams, etc.)/(0) preference for drier habitats Disturbed habitat Categorical 2 (1) Preference for disturbed habitats (e.g. roadsides or plantation)/(0) preference for undisturbed habitat Light Categorical 4 Species occurs primarily in: full sun/ full shade/ semi-shade/ all light forms Number of native regions (proxy for Continuous A count of native floristic regions (based on Takhtajan environmental tolerance) 1986) Number of native kingdoms (proxy for Continuous A count of native kingdoms (based on Takhtajan 1986) environmental tolerance) Number of introduced regions (proxy for Continuous A count of introduced floristic regions (based on Takhtajan popularity in horticulture and 1986) environmental tolerance) Residence time Continuous Years (calculated as the time elapsed between the earliest recorded year in the introduced region or earliest year of publication and the year 2017) Disturbed habitat 9 light Interaction To determine if light availability influences a fern’s occurrence in disturbed habitat) Number of introduced regions 9 life form Interaction To consider the types of life forms that are more widely introduced (* popularity in horticulture) Mode of regeneration 9 wet habitat Interaction To consider the importance of water in fern reproduction

for testing specific variables (Moodley et al. 2016; procedure. This ensured that no variables potentially Pysˇek et al. 2017). In our case, we forced residence explaining deviance were missed in the manual time and number of introduced regions to be in our backwards selection procedure. The variables identi- initial models as they have shown to have significant fied in these procedures were consistent across models effects in previous studies (Wilson et al. 2007; and therefore, for simplicity and ease of discussion, we Moodley et al. 2016). Ultimately, we fitted a logistic only presented the results of the manual backwards regression model using the backwards manual step- procedure. Since we aimed to build a usable (i.e. wise procedure to four potential initial models. simple) predictive model, we selected the models with To further test the robustness of our results, the a high explanatory power but with the least number of same process was then repeated using a manual significant variables necessary to explain the proba- forward stepwise selection procedure, and the function bility of becoming naturalised or invasive. A model ‘stepAIC’ from package ‘MASS’ (Venables and that is more biologically comprehensive and informa- Ripley 2002) and using both a backward and forward tion-laden is likely to explain a greater proportion of 123 Author's personal copy

866 E. J. Jones et al. the deviance but would be constrained by the avail- floristic kingdoms suggests little latitudinal constraint ability of information on various species. To assess the (Fig. 1). At the scale of floristic regions (FR) some predictive power of the final selected models we patterns were evident. The Eastern Asiatic (FR 2) and considered McFadden’s R squared values for logistic Irano-Turanian (FR 8) donated the greatest numbers of regression. The final model was used to calculate and species whereas few species originated from the plot the probability of an alien fern becoming natu- Mediterranean (FR 6), Indian (FR 16), and the ralised or invasive. All analyses were conducted with Indochinese (FR 17). Regions which received the the open source R software (version 1.1.383) (R most species were the Neozeylandic (FR 35), Hawai- Development Core Team 2013). ian (FR 21), and Circumboreal (FR 1), and although FRs 2 and 8 donated many species, they received few species. Specific species of concern that were shown to Results be invasive over extensive introduced ranges include Lygodium japonicum (Thunb.) Sw., Lygodium micro- Inventory, geographic distribution, and family phyllum (Cav.) R. Br., Adiantum raddianum C. Presl, representation Angiopteris evecta (G. Forst) Hoffm, Cyrtomium falcatum (L. f.) C. Presl, Macrothelypteris torresiana The inventory comprised 157 species of alien ferns (Gaudich.) Ching., Nephrolepis cordifolia (L.) C. (Supplementary 1), which is ca. 1.6% of the ca. 9500 Presl, Phlebodium aureum (L.) J. Sm., Pityrogramma recognised species of terrestrial polypodiophytes calomelanos (L.) Link, Pteris vittata L., and Sphaer- (after The Plant List). In terms of invasion status, opteris cooperi (F. Muell.) R.M. Tryon. 12% of the recorded species were introduced but not Twenty-four families were represented by alien naturalised, 49% were naturalised but not invasive, fern species. Alien species comprised 1.6% of all and 39% were invasive. Geographic distribution of recognised terrestrial polypodiophyte species. Fami- donated and received fern species at the scale of lies within which alien species were overrepresented

Fig. 1 Numbers of terrestrial alien Polypodiophyta (true fern) floristic regions of the world fall into 6 floristic kingdoms [based species donated by native floristic regions (grey circles) and on Takhtajan (1986)]. The size of the circle corresponds to received by introduced floristic regions (black circles). The 35 number of species 123 Author's personal copy

A global assessment of terrestrial alien ferns (Polypodiophyta) 867 relative to their size included the Psilotaceae, vegetatively significantly increased the likelihood of Nephrolepidaceae, Equisetaceae, Onocleaceae and changing from the ‘introduced’ status (transitions one Lygodiaceae (Fig. 2). In terms of absolute numbers and three) but had no effect on becoming invasive of alien species contributed, Pteridaceae (37 species), once naturalised (transition two). Similarly, disturbed Dryopteridaceae (21 species), Blechnaceae (12 spe- habitats also promoted transitions from ‘introduced’ to cies), Polypodiaceae (11 species), and Dennstaedti- other statuses, though marginally for transition two. aceae (11 species) ranked the highest (Fig. 2). Species with the ability to survive all types of light conditions or with a preference for full sun, had a Traits influencing invasiveness higher probability to transition to ‘‘invasive’’ (transi- tions two and three) than shade tolerant species. The final model of the manual backwards stepwise Ground-dwelling species proved more likely to selection procedure retained the variables mode of become invasive than epiphytes or lithophytes. Num- regeneration and number of introduced regions for the ber of native kingdoms (our best available proxy for transition from introduced to naturalised (transition 1); environmental tolerance) increased the likelihood to number of introduced regions, light, life form, and become invasive (transition three). disturbed habitat for the transition from naturalised to invasive (transition two); and number of introduced regions, light, disturbed habitat, number of native Discussion kingdoms, and mode of regeneration for the transition from introduced to invasive (transition three) Family and geographic representation (Table 2; Fig. 3). Growth form, wet habitat, and residence time had no significant effect. The McFad- Our global inventory of alien ferns showed that there den’s R squared values for logistic regression showed are significantly more alien species (157) than the ca. the variation explained by our models to be 30% for 60 species noted by Robinson et al. (2010). An transition one, 30% for transition two, 40% for estimated 3.9% of the global vascular flora have transition three. naturalised or become invasive (van Kleunen et al. Number of introduced regions significantly 2015) which is a significantly higher proportion than increased probability of species becoming naturalised what we found for alien ferns (0.02% are alien of or invasive. The ability to regenerate both sexually and which half have naturalised or become invasive).

Fig. 2 The prevalence of terrestrial alien species of Polypodiophyta (true ferns) in relation to family size (number of species), calculated as the proportion of the total number of species that are alien within each family, as well as for Polypodiophyta as a whole (respectively)

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Table 2 Variables retained by the stepwise backwards logistic ferns) transitioning from introduced to naturalised (transition regression (P \ 0.10) for significantly influencing the proba- one), naturalised to invasive (transition two), or introduced to bility of a terrestrial alien species of Polypodiophyta (true invasive (transition three) Dev P value Estimate SE

Transition one Intercept 0.041 0.768 Mode of regenerationa 7.556 0.006** 1.803 0.704 Number of introduced regions 2.911 0.088 0.627 0.571 Transition two Intercept - 4.648 1.647 Number of introduced regions 19.875 8.267e-06*** 0.320 0.105 Lightb 12.250 0.007** All: 2.596 0.970 Semi-shade: 0.838 0.852 Sun: 1.057 0.963 Life formc 3.579 0.059 2.410 1.386 Disturbed habitatd 3.091 0.079 0.771 0.439 Transition three Intercept - 4.450 1.160 Number of introduced regions 18.956 1.337e-05*** 0.305 0.108 Lightb 12.678 0.005** All: 2.912 1.051 Semi-shade: 1.273 0.974 Sun: 1.910 1.080 Disturbed habitatd 3.885 0.049* 0.929 0.465 Number of native kingdoms 4.048 0.044* 0.435 0.236 Mode of regenerationa 4.399 0.036* 0.947 0.465 aThe reference level included in the intercept is sexual or vegetative reproduction only; the estimate displayed is for a species displaying both modes of regeneration bThe reference level included in the intercept is shade; the estimate displayed is for all types of light, semi-shade and sun cThe reference level included in the intercept is epiphyte or lithophyte; the estimate displayed is for ground-dwelling species dThe reference level included in the intercept is for a species showing preference for undisturbed habitat; the estimate displayed is for a species showing preference for disturbed habitat

However, due to the poor recording of alien ferns and introduced regions had a significant effect on species their invasion status in inventories, there are likely to at each stage of transition, and species with a higher be more alien fern species than we recorded. In fact, a number of native kingdoms showed a greater proba- fern is likely to be noted only once it has become an bility of becoming invasive than those with a smaller established and ecologically damaging invader (de native range. In general, climate, species specific Winter and Amoroso 2003), which likely explains the ecological requirements, ease of dispersal and the underrepresentation of introduced species in our availability of suitable habitat largely determine the study. distribution of fern species (Kessler 2010). In our Similar studies screening for invasiveness identi- study however, the geographical distribution of fied a strong relationship between invasion status and donated and received species (Fig. 1) appears to have the extent of the species’ native and introduced ranges been determined largely by anthropogenic influences (Rejma´nek and Richardson 1996; Pysˇek et al. 2009; as no particular longitudinal patterns are evident. Moodley et al. 2013; Moodley et al. 2016; Latombe Furthermore, all species were introduced for horticul- et al. 2017). Similarly, in our study, number of tural purposes. Floristic regions with large numbers of

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A global assessment of terrestrial alien ferns (Polypodiophyta) 869

Fig. 3 The relative probability of a terrestrial alien species of significant. We fixed model variables not displayed in each Polypodiophyta (true ferns) transitioning from a introduced to graph to their intercept values to better describe the relative naturalised (transition one), b–d naturalised to invasive probabilities associated with the variations of the variable (transition two), or e–h introduced to invasive (transition three) displayed in addition to number of introduced regions. For for significant variables (details in Table 1) in relation to the binary variables, 1’s and 0’s follow the descriptions provided in effect of number of introduced regions as it was always Table 1 donated or received fern species typically had (1) an in horticulture. This is in line with Van Kleunen et al. overrepresentation of alien or invasive plants gener- (2018) whom showed that although not all popular ally (e.g. on islands such as England, New Zealand and horticultural plants are invasive, the vast majority Hawaii; Vernon and Ranker 2013); (2) well-studied (75–93%) of the current global naturalised alien flora alien fern invasions (e.g. Hawaii, FR 21; Wilson are those with ornamental horticultural origins, and 2002); (3) many native fern species with horticultural that horticulture still plays a significant role in value (e.g. Southeast Asia, FR 2 and 8; de Winter and introduction of plants across the globe. In our inven- Amoroso 2003); and (4) long histories of horticultural tory of alien ferns, families within which aliens were introductions (e.g. Europe, FR1, Hawaii, FR 21 and overrepresented often had species that were invasive New Zealand, FR 35; van Kleunen et al. 2018; Smith over extensive introduced ranges and were popular in 1895). These findings compare well with trends horticulture (Fig. 2; Supplementary 1). The recorded observed in alien angiosperms (Richardson et al. families generally concur with those suggested by 2011; Moodley et al. 2013; van Kleunen et al. 2018). horticultural plant guides, e.g. Young (1996) listed Ferns are selected in horticulture for their full species from the families Pteridaceae, Blechnaceae, foliage appearance, compact size, evergreen habit, Davalliaceae, Dennstaedtiaceae, Nephrolepidaceae, unique characteristics (colour, texture or shape), high and Lygodiaceae; and species such as Lygodium reproductive ability, fast growth rate, and high envi- japonicum (Thunb.) Sw., Lygodium microphyllum ronmental tolerance (de Winter and Amoroso 2003). (Cav.) R. Br., Angiopteris evecta (G. Forst) Hoffm., Plant traits that are popular in horticulture often Pteris vittata L., and Sphaeropteris cooperi (F. Muell.) facilitate the invasiveness of a species (Dehnen- R.M. Tryon. were identified as species of concern in Schmutz et al. 2007). In our study, we interpreted our study but have also previously been identified as number of introduced regions as a proxy for popularity

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870 E. J. Jones et al. serious invaders (Medeiros et al. 1992; Robinson et al. invasive behaviour in alien ferns by increasing growth 2010). and subsequent regeneration. Ferns thrive in urban Our study supports the notion that progression environments and can establish successfully in and on along the introduction-naturalisation-invasion contin- manmade surfaces such as the under hangs of bridges, uum is mediated by stage-dependant traits (Richard- old cracked walls, and drainage canals (Morajkar et al. son and Pysˇek 2012; Moodley 2016). The general 2015). In South Africa, Sphaeropteris cooperi (F. likelihood of an alien fern species becoming natu- Muell.) R.M. Tryon. occurs in higher densities in ralised or invasive once introduced was high (Fig. 3) commercial timber plantations (associated with dis- compared to what is known for other taxa (Williamson turbance) than in undisturbed indigenous forest (E and Fitter 1996). Alien ferns have an 80% chance of Jones, unpublished data). Fern species have also been becoming naturalised if they possess the ability to found in great densities in vanilla plantations in regenerate both sexually and vegetatively. Mode of Mexico (Mehltreter 2006) and in oil plantations in regeneration is often a significant predictor of invasive parts of Indonesia (Sofiyanti 2013). success in various species (Kolar and Lodge 2001) but We found that alien ferns with a ground-dwelling is not necessarily a consistent predictor across all taxa. life form, rather than epiphytic or lithophytic, were In Proteaceae, invasiveness was related to regenera- more likely to become invasive. Similarly, ground- tion mode where resprouters were more likely to dwelling alien ferns accounted for most of the invasive naturalise while reseeders were more likely to invade fern species recorded in Hawaii, whereas very few (Moodley et al. 2013), but no relationship was evident were epiphytic (Robinson et al. 2010; Wilson 2002). in Araceae (Moodley et al. 2016). The combination of In contrast to ground-dwellers, epiphytes are generally multiple reproductive modes and the ability to occupy limited by the availability of the particular surfaces on sun-exposed sites are dual traits shared by many which they grow and are more likely to be exposed to invasive fern species (Robinson et al. 2010; Arosa water stress because they are rooted in shallower et al. 2012). Higher light conditions/availability can substrates (Mehltreter and Sharpe 2013). However, enable faster growth rates which in turn should exceptions do exist, for instance Platycerium bifurca- increase invasiveness, whereas shaded environments tum (Cav.) C. Chr. grows in large colonies in its native can limit the spread of various fern species (Mehltreter (Pemberton 2003) and invaded (EJJ pers. obs.) habitat, and Sharpe 2013). Accordingly, the ability to survive where it is able to form extensive chains within a under all light forms or high light conditions (e.g. the single tree and commonly spreads to trees adjacent to highly invasive Angiopteris evecta (G. Forst.) in the parent population. Just as certain ground-dwelling Hawaii, Christenhusz and Toivonen 2008) increased species may depend on particular soil characteristics, the probability of alien ferns becoming invasive, so too do epiphytic and lithophytic species depend on whereas strictly shade-loving species held a lower the particular characteristics of their host substrate, potential for invasiveness. Furthermore, ferns that therefore a greater understanding of how environmen- have characteristics which allow them to survive in tal factors influence richness amongst fern life forms is habitats of low nutrients and high-light conditions are needed (Richardson and Walker 2010). best adapted to grow in disturbed areas (Walker and Propagule pressure is another significant predictor Sharpe 2010). of invasiveness in various plant taxa (Colautti et al. Disturbance, especially those caused by human 2006) and involves the number of reproductive activities (e.g. landslides, cliffs, roads and railways, propagules and the rate at which they arrive in an fire regimes, and plantations) commonly promotes the area per unit time (Williamson and Fitter 1996; spread and proliferation of invasive plants and gener- Simberloff 2009). Some studies screening for inva- ally reduces resistance to invasion by intact native siveness used several measures as a proxy for communities (Richardson et al. 2011; Baard and propagule pressure, one of which is the number of Kraaij 2014; Terzano et al. 2018; Hobbs and Huen- introduced regions (Colautti et al. 2006; Zenni and neke 1992). In our study disturbance facilitated the Simberloff 2013; Moodley et al. 2016). Although transition from naturalised to invasive in alien fern introductions of a species across numerous floristic species, similarly Robinson et al. (2010) and Walker regions may in some cases concur with extensive and Sharpe (2010) found that disturbance promoted introduction efforts within a region (and as such serve 123 Author's personal copy

A global assessment of terrestrial alien ferns (Polypodiophyta) 871 as a proxy for propagule pressure), this relation cannot highlighted that a ground-dwelling life form, repro- be assumed, particularly at the scale of global floristic ductive plasticity, tolerance for disturbance and varied regions. We argued that the introduction of a species light conditions, and a broad introduced range (hence a within one floristic region cannot facilitate invasion of high environmental tolerance and popularity in horti- that species in another floristic region and rather culture) are important determinants of invasiveness. interpreted number of introduced regions, and number Furthermore, our study supported that there are of native kingdoms (at yet a larger spatial scale), as invasion-stage dependant effects, whereby a trait or proxies for environmental tolerance (cf. Dehnen- set of traits becomes important during different Schmutz et al. 2007). In our study, a larger number invasion stages (Pysˇek et al. 2009). We found that of native kingdoms significantly promoted the transi- some mechanisms driving invasiveness in alien ferns tion to invasive suggesting that high environmental are similar to those in other taxa, e.g. thriving under tolerance in alien ferns increases their invasive high light conditions and disturbance (Richardson and potential. Pysˇek 2012). Horticulture is a well-documented driver Additional factors that could not be assessed in this of invasiveness in various alien species (Dehnen- study include aspects such as such as leaf life span Schmutz et al. 2007) and appeared to have been highly (Mehltreter and Sharpe 2013), frond size, plant size, influential in the spread and successful establishment growth rate, spore load and longevity (Durand and of alien ferns, supported by the significant influence of Goldstein 2001), the ability to alter soil function (Chau number of introduced regions as a predictive variable. et al. 2013), the use of chemical defence, and the Terrestrial ferns have to date been largely overlooked presence of natural enemies or predators (Robinson as a likely invasive taxon, but this study showed that et al. 2010). These traits were considered in other some ferns have high invasive potential. We identified studies on invasive ferns and are traits displayed by additional biological traits of ferns that may influence popular horticultural species, they are likely to influ- invasiveness and warrant further study. Divergent ence invasiveness in alien ferns and warrant further ecological requirements and tolerances of the two life investigation. Furthermore, although the life stages of stages (gametophyte and sporophyte) of ferns may be a fern (i.e. gametophyte and sporophyte) are consid- of particular importance in their invasion success. In ered independent and their ecological requirements for conclusion, this study initiated the identification of survival differ, it is the gametophytic life stage that traits associated with invasiveness in ferns and high- determines the site of origin of the sporophyte (Sharpe lighted aspects that require further investigation. et al. 2010). As such, the sporophyte is forced to adapt to the site ‘chosen’ by the gametophyte, and it is at this Acknowledgements This work was supported by the South stage that the greatest number of individuals fail (Page African National Department of Environment Affairs through its funding of the South African National Biodiversity Institute 2002) e.g. gametophytes of some species have been Invasive Species Programme and by Nelson Mandela recorded as being more stress tolerant (Sato and Sakai University (Grant No. P010). We thank Ronel Klopper whom 1981) and inhabiting areas inhospitable (Peck et al. extracted relevant data from the PRECIS database, and Neil 1990) to their sporophyte form. There is an evident Crouch for his invaluable advice and guidance. contrast in the ecology of gametophytes and sporo- Compliance with ethical standards phytes (Page, 2002) and the manner in which the disparate requirements of these different life stages Conflict of interest The authors declare that they have no affect species’ distribution ranges or their invasive conflict of interest. potential has not yet been explored but may further explain distribution and invasiveness in alien ferns (Sharpe et al. 2010). References

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123 Species Synonyms (The Plant List) Common Name Family Invasion status Mode of regeneration Life Form Habitat Light Condition Native range Native floristic region Introduced range Inroduced floristic Region Assumed date of Introduction Latest publication date Residence time Invasion Status (source) Motivation Source

Adiantum capillus‐veneris L. Adiantum paradiseae Baker Southern maidenhair fern Pteridaceae Naturalised Sexual Ground‐dwelling moist areas where it typically grows on SS West and South Europe, Africa, North 1, 3, 4, 9, 21, 23 Trinidad and TabagoNew ZealandMediterra 25 1889 2000 111 Introduced species till exists but there is no report of Baksh‐Comeau, 2000 Black maidenhair Lithophyte rock faces and in crevices of cliffs on America Central America and Hawaiian spread Robinson et al 2010 Adiantum caudatum L. Adiantum lyratum Blanco Walking maiden fern Pteridaceae Introduced Sexual Ground‐dwelling On rather dry slopes or often on muddy SS Asia 2, 8 Florida 3 1987 2017 30 Introduced no further information documenting https://plants.usda.gov/core/profile?symb Lithophyte limestone usually in dry deciduous forests (http://www virtualherbarium org/vh/db/ spread ol=ADCA3 Adiantum concinnum Humb. & Bonpl. ex Willd. Brittle maidenhair Pteridaceae Introduced Sexual Ground‐dwelling Forest edges, roadsides SS Central America, Western South America 27, 23 Sri Lanka 16 1954 1982 28 Introduced Alien no further information documenting Sledge, 1982 Polished maidenhair Lithophyte and West Indies (https://www gbif org/occurrence/114064 spread Adiantum diaphanum Blume Adiantum setulosum J. Sm. Filmy maidenhair Pteridaceae Introduced Sexual Ground‐dwelling in forest , along streams, or near SS Tropical Asia, East Australia, New Zealand 2, 17, 29, 18, 19. 20, 21, 22 Sri Lanka 16 1982 2017 112 Introduced Alien no further information documenting Sledge, 1982 Lithophyte waterfalls and the Pacific Islands spread Adiantum 'Edwinii' Pteridaceae Naturalised Covers entire cliff‐faces and rock slopes Hawaii? 21 Hawaii 21 1981 1996 15 Naturalised (Vernon, 2013) no further information documenting Wilson, 1996 spread Vernon 2013 Adiantum hispidulum Sw. Adiantum hispidulum f. strictum Gilbert Rough maidenhair Pteridaceae Naturalised Both Ground‐dwelling Moist areas, near rocks in rainforest or SS Africa, Australia, Polynesia, Malesia, New 7, 12, 10, 13, 11, 28, 29, 30, 31, 20, 18, 35, AzoresMadeira 5 2002 2017 15 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ five‐fingered jack Lithophyte open forest (Australia) Zealand and other Pacific Islands 19 20 22 aliens org/speciesFactsheet do?speciesId= Adiantum latifolium Lam. Adiantum fovearum Raddi Broadleaf maidenhair Pteridaceae Introduced Sexual Ground‐dwelling slopes or on the ground of rainforest SS‐Shade Tropical America from Mexico to South 23, 24, 25, 26, 27, 33 Sri Lanka 16 1982 1982 0 Introduced Alien no further information documenting Sledge, 1982 where the canopy is open In Mexico it America as well as the Greater Antilles spread Adiantum pulverulentum L. Adiantum monotis Nees Glossy maidenhair Pteridaceae Introduced Sexual Ground‐dwelling All Andean tropics 27, 3, 4, 9 Sri Lanka 16 1982 1982 0 Introduced Alien no further information documenting Sledge, 1982 Adiantum propinquum Fée America spread Adiantum trapeziforme L. Giant maidenhair Pteridaceae Naturalised Both Ground‐dwelling Sun‐SS Central and South America 23, 24, 25, 26, 27, 33 Fiji, Sri Lanka 19 1965 2011 46 Introduced the species appears to be well established Brownsey & Perrie, 2011 in several places http://www catalogueoflife org/col/detail Adiantum hispidulum Sw. Adiantum hispidulum f. strictum Gilbert Rough maidenhair Pteridaceae Invasive Apogymous Ground‐dwelling A. hispidulum usually begins to colonize in All Africa, Australia, Polynesia, Malesia, New 7, 12, 10, 13, 11, 28, 29, 30, 31, 20, 18, 35, HawaiiSoutheastern USA 21 1923 1996 73 widely naturalised clearly spreading beyond source Wilson, 1996 Rosy maidenhair Lithophyte areas where there is some type of natural Zealand and other Pacific Islands 19 20 24 25 naturalised (Vernon 2013) completely Vernon 2013 Adiantum lunulatum Burm. f. Adiantum philippense L. Pteridaceae Naturalised Both Ground‐dwelling In forests, thickets, or wooded ravines, Shade Widely distributed in the tropics through 10, 12, 2, 8, 29, 31, 3, 9, 23, 24, 25, 26, 27 America 3, 4, 9 1982 1982 0 Adventive The term adventive refers to a population Tyron & Tyron, 1982 most commonly in rocky soil on banks of Africa Asia Australia Central America and akin to casual/ established ‐ but not Adiantum poiretii Wikstr. Adiantum thalictroides Willd. ex Schltdl. Pteridaceae Introduced Ground‐dwelling extends into mountain ranges here it SS Africa, Indian Ocean Islands, Asia Tristan 7, 12, 10, 11, 13, 28, 15, 1, 2, 8, 25, 26, 27 Sri Lanka 16 1982 1982 0 Introduced Alien no further information documenting Sledge, 1982 Adiantum pellucidum M Martens & Lithophyte grows on mossy earth banks in evergreen da Cunha tropical America spread Adiantum polyphyllum Willd. Adiantum cardiochlaena Kunze Pteridaceae Introduced Ground‐dwelling on banks SS Mesoamerica, tropical South America 23, 24, 25, 26, 27, 33 Trinidad and TabagoEurope, Germany, Muni25 1889 2000 111 Introduced no further information documenting Baksh‐Comeau, 2000 spread Adiantum raddianum C. Presl Adiantum cuneatum G. Forst. New world maidenhair Pteridaceae Invasive Both Ground‐dwelling It is found in a wide range of habitats SS South America 24, 25, 26, 27, 33 MadeiraHawaiiSri LankaIndiaIndonesiaNe w5 1911 2017 106 Naturalised Widespread https://www.cabi.org/isc/datasheet/3237 Delta Maidenhair including forest floors rock crevices walls Wagner 1950 Adiantum tenerum Sw. Adiantum extensum Fée Brittle maidenhair Pteridaceae Naturalised Sexual Ground‐dwelling Limestone ledges, sink walls, and grottoes SS Central America, Florida, Peurto Rico, 23, 3, 27, 28, 25 Trinidad and TabagoSingaporeHawaii 18 2000 2017 122 Naturalised Description of behaviour https://florafaunaweb.nparks.gov.sg/spec Adiantum trapezoides Fée Venezuala ial‐pages/plant‐detail aspx?id=1537 Amblovenatum opulentum J.P. Roux Thelypteris opulenta (Kaulf.) Fosberg Jeweled Maiden fern Thelypteridaceae Naturalised Ground‐dwelling Shaded banks, gullies, stream banks, and Shade East Africa, Seychelles, through to 10, 12, 15, 2, 18, 19, 20 Trinidad and TabagoAn lles, MesoamericaS 25 1934 2000 66 Inroduced ‐ common Beyond introduced but no evidence of Baksh‐Comeau, 2000 disturbed forest slopes southern Asia to the Pacific Islands (Tahiti) invasive status https://www cabi org/isc/datasheet/1194 Anemia phyllitidis (L.) Sw. Anemia fraxinifolia Raddi Blooming fern Anemiaceae Introduced Ground‐dwelling Mexico, Central America, tropical South 23, 25, 26, 27 Sri Lanka 16 1982 1982 0 Introduced Alien no further information documenting Sledge, 1982 Anemia haenkei C Presl America and the West Indies spread Angiopteris evecta (G.Forst) Hoffm Polypodium evectum G. Forst. Oriental vessle fern Marattiaceae Invasive Both Ground‐dwelling moist forest and rainforest at low to All American Samoa 17, 18, 19, 20, 22, 29, 30, 37, 40, 34, 39, 31, Hawaii (US)Costa RicaSri LankaJamaicaFlor 21 1927 2008 81 naturalised Clear spread over long distance as well as Christenhusz, 2008 middle elevations and appears to Australia 35 36 38 41 32 33 population and number increase since http://www iucngisd org/gisd/speciesnam Angiopteris lygodiifolia Rosenst. Mules foot fern Marattiaceae Naturalised Both Ground‐dwelling Ravines and stream banks All Japana and Taiwan 2 Korea 2 2017 0 Adventive Reliable source definitions https://worldplants.webarchiv.kit.edu/fer ns/ Asplenium aethiopicum (N.L.Burm.) Aspleniaceae Invasive Apogymous All Boulders and rock crevices in seasonally Sun Africa 7,10,12,13,11,28 New Zealand 35 2003 2017 14 Naturalised Increasing ground in Auckland http://www.nzpcn.org.nz/flora_details.as Becherer moist montanious regions px?ID=4145 Asplenium foresiense Legrand Aspleniaceae Naturalised Apogymous Ground‐dwelling Rocky areas SS Iberian Peninsula, France, the Apennine 6, 1, 8 Germany 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ Peninsula Central Europe and the western aliens org/speciesFactsheet do?speciesId= Asplenium scolopendrium L. Phyllitis scolopendrium (L.) Newman Harts‐tongue fern Asplenianceae Introduced Both Ground‐dwelling eutral and lime‐rich substrates, including All Europe and North America 1, 3, 4, 9 Falkland IslandsMount Philomel ‐ West Falk 33 1968 2003 35 Introduced, very rare Source explanation http://www.europe‐ moist soil and damp crevices in old walls aliens org/speciesFactsheet do?speciesId= Asplenium x lucrosum Perrie et Brownsey Asplenium bulbiferum ‐ mistaken for Hen and Chicken fern Aspleniaceae Naturalised Vegetative Ground‐dwelling Britain? 1 New Zealand 35 1954 (Perrie et al, 2005) 2017 63 Casual adventive is ‘‘passively regenerating only in the http://blog.tepapa.govt.nz/2009/04/30/th immediate e‐false‐hen‐and‐chickens‐fern/ Athyrium filix‐femina (L.) Roth Lady fern Athyriaceae Naturalised Sexual Ground‐dwelling commonly found growing under trees or SS‐Shade Most of Temperate northern hemisphere 3,4,9,5,7,6,1,8,2 New Zealand 35 1976 1985 9 Adventive The term adventive refers to a population Brownsey, 1985 alongside stumps in moist to wet forests (http://www nzpcn org nz/flora details as akin to casual/ established ‐ but not Athyrium otophorum (Mig.) Koidz. Eared lady fern Athyriaceae Naturalised Sexual Ground‐dwelling Moist rocky areas SS‐Shade Japan 2 New Zealand 35 2003 2017 14 Naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as spread px?ID=4163 Balantium antarcticum (Labill.) C. Presl Dicksonia antarctica Labill. Soft tree fern Dicksoniaceae Invasive Sexual Ground‐dwelling Damp, sheltered woodland slopes and SS‐Shade Southeastern Australia and Tazmania 29, 31 Sao Miguel isalnd (Azores)(not naturalized in5 1850's 2012 162 Naturalised The species has invaded forest Arosa, 2012 moist gullies and they occasionally occur plantations exotic forests and two Jermy 1978 Blechnum appendiculatum Willd. Blechnum glandulosum var. distans (C. Palm Fern Blechnaceae Invasive Both Ground‐dwelling in mesic forests, particularly on rocks or Shade Americas: 3, 9, 23, 24, 25, 26, 27, 33 Hawaii 21 1917 (Wilson, 2002) 2013 96 Naturalised clearly spreading beyond source Vernon, 2013 Presl) C Chr Lithophyte rocky substrates Texas and Florida in the USA down as far https://www cabi org/isc/datasheet/1189 Blechnum cordatum (Desv.) Hieron Blechnum chilense (Kaulf.) Mett. Chilean hard fern Blechnaceae Naturalised Both Ground‐dwelling Moist woodland SS‐Shade Temperate South America 33 Great BritainIreland 1 1978 2017 39 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ aliens org/speciesFactsheet do?speciesId= Blechnum punctulatum Sw. Blechnaceae Naturalised Both Ground‐dwelling long mountain streams in scrub or along Shade Africa 7,12,10,11,13,18 New Zealand 35 2005 2017 12 Naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as Lithophyte moist forest margins spread px?ID=4139 Blechnum spicant (L.) Roth Hard‐fern Blechnaceae Invasive Sexual Ground‐dwelling Woods, heaths, moors, mountain All Europe and Western North America 1, 4, 9, 10 Brish Isles (weer parts)Sweden 1 1978 2017 39 Alien ‐ widespread Due to plants behaviour, also described as Jermy, 1978 Deer‐fern grassland and on rocks widespread ‐ although limited by certain http://www europe‐ Blechnum gibbum Mett. Silver lady fern Blechnaceae Introduced Sexual Ground‐dwelling forested areas with high humidity and SS Fiji, New Caledonia and the Pacific Islands 18, 19, 20, 21, 22 Fiji 19 1997 2011 14 Introduced recorded only once from an unlocalised Brownsey & Perrie, 2011 Dwarf tree fern moist fertile soils specimen ‐ naturalised? Blechnum occidentale L. Blechnum appendiculatum (Robinson et al. Hammock Fern Blechnaceae Invasive Both Ground‐dwelling Rocky and clayey places near seasonally SS‐Shade New Wold tropics 24, 25, 26, 28, 27, 29 HawaiiSri LankaAzores 21 1917 2017 100 Abundant ‐widely naturalised The plant is listed as abundant by more Wagner, 1950 2010) dry streams shady hammocks or open Tropical America (Robinson et al 2010) that one source Robinson et al 2010 Blechnum orientale Blechnaceae Invasive Australia, East and Southeast Asia, Pacific 30, 31, 29, 2, 18, 19, 20, 21, 22, 23 Australia Tropics of Southeast Asia 29, 30, 31 2010 2010 0 Native invasive species Clearly showing invasive behaviour Robinson et al. 2010 Islands Blechnum orientale Blechnaceae Invasive Australia, East and Southeast Asia, Pacific 30, 31, 29, 2, 18, 19, 20, 21, 23 Tropics of Southeast Asia 2 2010 2010 0 Native invasive species Clearly showing invasive behaviour Robinson et al. 2010 Islands Blechnum orientale L. Blechnaceae Naturalised Both Ground‐dwelling open lowland forest ‐ often on slopes Sun‐SS Australia, East and Southeast Asia, Pacific 30, 31, 29, 2, 18, 19, 20, 21, 24 Hawaii 21 2010 2017 7 Naturalised New record, no evidence of spread yet Vernon, 2013 Islands Blechnum penna‐marina (Poir.) Kuhn Antarctic hard fern Blechnaceae Naturalised Both Ground‐dwelling The natural habitat of this fern is Sun‐SS Chile, Argentina ‐ also New Zealand, 33, 35, 29, 30, 31, 18, 19, 20, 21, 22 British Isles 1 1978 1978 0 escaped and established established but no report of spread Jermy, 1978 grasslands stream banks rock crevices australia and some Pacific Islands Ceterach officinarum Willd. Asplenium ceterach L. Rustyback fern Aspleniaceae Naturalised Sexual Ground‐dwelling limestone rocks, and mortared walls Sun Western and Central Europe 1 Austria 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ Lithophyte aliens org/speciesFactsheet do?speciesId= Cheilanthes lendigera (Cav.) Sw. Broad lip fern Pteridaceae Naturalised Sexual Ground‐dwelling Rocky slopes and ledges Sun Mexico 23 New Zealand 35 2003 2017 14 Naturalised no further information documenting http://www.fernsoftheworld.com/2012/1 spread 2/05/cheilanthes‐lendigera‐cav‐sw/ Cheilanthes viridis Pellaea viridis Pteridaceae Naturalised Sexual Ground‐dwelling Shaded forest floors in evergreen mid‐ Shade Southern Africa, India, Asia 28, 11, 12, 16, 2, 16 Australia 29, 30, 31 2010 2010 0 Naturalised (Vernon, 2013) no further information documenting Robinson et al. 2010 altitude forest (where it is sometime spread Cheilanthes viridis Pellaea viridis Pteridaceae Naturalised Sexual Ground‐dwelling Shaded forest floors in evergreen mid‐ Shade Southern Africa, India, Asia 28, 11, 12, 16, 2, 17 New zealand 35 2010 2010 0 Naturalised (Vernon, 2013) no further information documenting Robinson et al. 2010 altitude forest (where it is sometime spread Cheilanthes viridis Pellaea viridis Pteridaceae Naturalised Sexual Ground‐dwelling Shaded forest floors in evergreen mid‐ Shade Southern Africa, India, Asia 28, 11, 12, 16, 2, 18 Florida 3 2010 2010 0 Naturalised (Vernon, 2013) no further information documenting Robinson et al. 2010 altitude forest (where it is sometime spread Cheilanthes viridis Sw. Pellaea viridis Green Cliff Brake Pteridaceae Naturalised Sexual Ground‐dwelling Shaded forest floors in evergreen mid‐ Shade Southern Africa, India, Asia, Madagascar 28, 11, 12, 16, 2, 15 Hawaii 21 1928 2012 84 Naturalised (Vernon, 2013) no further information documenting Wilson, 1996 altitude forest (where it is sometime spread Vernon 2013 Cheilanthes notholaenoides (Desv.) Maxon Royal lip fern Pteridaceae Introduced Sexual Ground‐dwelling Typical form grows on rocky banks in Sun Guatemala, Mexico, Venezuela, 23, 25 US ‐ Lower 48 states 3, 4, 9 1985 2017 32 Introduced no further information documenting https://plants.usda.gov/core/profile?symb ex Weath Lithophyte montane rain‐forest Mesoamerica spread ol=CHNO2 Christella dentata Soft fern Thelpteridaceae Invasive Sexual Ground‐dwelling SS Asia, Africa, Australia, New Zealnd (Old 7, 11, 12, 10, 13, 28, 2, 8, 35 Central America/ Carribean 23 2010 2010 0 Alien listed for invasiveness or potential for Robinson et al. 2010 Downy maiden fern World Tropics) negative impacts Christella dentata (Forssk.) Cyclosorus dentatus (Forssk.) Ching Soft fern Thelpteridaceae Invasive Sexual Ground‐dwelling is regarded as a facultative wetland plant. SS Asia, Africa, Australia, New Zealnd (Old 7, 11, 12, 10, 13, 28, 2, 8, 35, 39, 38, 37, 36, HawaiiTrinidad and TabagoUSA:AlabamaAr k21 1887 2012 125 Abundant Reliable source definitions Wagner, 1950 Thelypteris dentata (Forssk ) EP St John Downy maiden fern Both in its native and introduced ranges World Tropics) 40 41 Vernon 2013 Cyclosorus parasiticus (L.) Farw. Parasitic maiden fern Thelypteridaceae Invasive Sexual Ground‐dwelling C. parasiticus grows well in mesic forest All Widespread ‐ Tropical Asia, Some 2, 20, 7, 12, 10, 13, 11, 28, 15, 17, 16 HawaiiIndia (extra‐limital)China (extra‐limit 21 1926 2017 91 Invasive specifically listed as such https://www.cabi.org/isc/datasheet/1203 edges disturbed sites gullies humid Polynesian Islands Africa Madagascar 68 Cyrtomium falcatum Japanese Holly Fern Dryopteridaceae Naturalised Apogymous Ground‐dwelling favours mesophytic or coastal habitats SS‐Shade East Asia 2 Macaronesia 5 Unspecified 2010 0 Introduced ‐ common Beyond introduced but no evidence of Robinson et al. 2010 Lithophyte In its introduced range C falcatum can be invasive status Cyrtomium falcatum (L. f.) C. Presl Japanese Holly Fern Dryopteridaceae Invasive Apogymous Ground‐dwelling favours mesophytic or coastal habitats SS‐Shade East Asia 2 USASouth Africa:Western CapeEastern Cape3, 4, 9 1907 ‐ New Jersey 2017 110 Naturalised clearly spreading beyond source http://www.calflora.org/cgi‐ Lithophyte In its introduced range C falcatum can be bin/species query cgi?where‐ Cyrtomium fortunei J. Sm. Fortunes holly fern Dryopteridaceae Naturalised Apogymous Ground‐dwelling Masonary, clay banks, mesic SS‐Shade Japan, Korea, southeast China, Vietnam 2, 8, 9, 10 BelgiumFranceItaly 1 2011 2017 6 Alien ‐ not established Described as casual http://www.europe‐ ravines Limestone crevices in open areas and eastern Thailand (https://www cabi org/isc/datasheet/113 aliens org/speciesFactsheet do?speciesId= Cystopteris bulbifera (L.) Bernh. Bulblet fern Woodsiaceae Naturalised Both Lithophyte It is found only on calcareous substrates SS‐Shade Canada and Eastern USA, Southwestern 1, 3, 9 Czech Republic 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ such as limestone It commonly festoons USA aliens org/speciesFactsheet do?speciesId= Cystopteris fragilis (L.) Bernh. Brittle bladder‐fern Dryopteridaceae Naturalised Both Ground‐dwelling cliffs at higher elevations, Talus and rocky SS‐Shade North, Central and South America 3,4,9,23,24,25,26,27,33 New Zealand 35 1899 (nzpcn) 2017 118 Adventive The term adventive refers to a population http://www.nzpcn.org.nz/flora_details.as Lithophyte slopes akin to casual/ established ‐ but not px?ID=3784 Davallia fejeensis Hook. Lacy Hare's foot Davalliaceae Naturalised Both Epiphyte moss‐covered rocks and trees in sub‐ SS Fiji Islands 19 Hawaii 21 2007 2013 6 naturalised no further information documenting Vernon, 2013 tropical forests spread Davallia griffithiana Hook. Davalliaceae Naturalised Both Ground‐dwelling Forested areas as well as urban areas on SS India, Bhutan, Burma, Vietnam, Laos, 16,2,8 New Zealand 35 1987 2017 30 naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as Lithophyte walls China Japan spread px?ID=4144 Davallia mariesii Baker Squirrels foot ferm Davalliaceae Naturalised Both Epiphyte Forested areas Shade Japan and eastern Asia 2,8 New Zealand 35 1987 2017 30 naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as spread px?ID=4172 Dennstaedtia davallioides T. Moore Lacy ground fern Dennstaedtiaceae Naturalised Both Ground‐dwelling occurs on rainforest margins or moist sites SS‐Shade Eastern Australia 23, 29 New Zealand 35 1905 2010 105 naturalised ‐ potential for invasive One locality no evidence of spread yet, but Heenan, 2010 in tall open forest ‐ in Australia is red flagged Dennstaedtia samoensis (Brack.) T.Moore Dennstaedtiaceae Introduced Ground‐dwelling Sun‐SS Samoa and Soloman Islands 18 New Zealand 35 2011 2017 6 Naturalised Collected once as a weed ‐ no further http://www.nzpcn.org.nz/flora_details.as reports of population or spread px?ID=6739 Dennstaedtia punctilobula (Michx.) T. Hay‐scented fern Dennstaedtiaceae Invasive Both Ground‐dwelling damp or dry acidic soils in woods or open SS‐Shade North America 3, 4, 9, 10 North Eastern USASweden 3 1999 2010 11 Native invasive species Reliable source definitions Fei, 2010 Moore woods de la Cretaz & Kelty 1999 Deparia japonica (Thunb.) M. Kato Lunathyrium japonicum (Thunb.) Sa. Japanese lady fern Athyriaceae Invasive Sexual Ground‐dwelling Coastal, mist‐belt and montane forest, on SS‐Shade China, Japan, Polynesia, New Zealand, 8,2,20,35, 29, 30, 31, 2, 18, 16, 17 South AfricaSwaziland 11, 12 1978 (Crouch, 2011) 2017 39 Naturalised (Roux, 2009) Clearly indicated in book Klopper & Crouch, 2010 Kurata Lithophyte damp mossy rocks usually next to a small Australia Thailand Malaysia and India Roux 2009 Deparia petersenii Athyriopsis japonica auct. non (Thunb.) Petersen’s lady fern Athyriaceae Invasive Both Ground‐dwelling along riverbanks in ravines, on bare earth All Himalayas, southern India and Sri Lanka in 8,2,20,35, 29, 30, 31, 2, 18, 19 Reunion Island 15 Not specified 2010 0 Naturalised clearly spreading beyond source Robinson et al. 2010 Ching banks near streams on moist shady rocks the west to western and southern China Deparia petersenii Athyriopsis japonica auct. non (Thunb.) Petersen’s lady fern Athyriaceae Invasive Both Ground‐dwelling along riverbanks in ravines, on bare earth All Himalayas, southern India and Sri Lanka in 8,2,20,35, 29, 30, 31, 2, 18, 20 MadeiraAzores 5 Not specified 2010 0 Naturalised clearly spreading beyond source Robinson et al. 2010 Ching banks near streams on moist shady rocks the west to western and southern China Deparia petersenii (Kunze) M. Kato Athyriopsis japonica (Thunb.) Ching Petersen’s lady fern Athyriaceae Invasive Both Ground‐dwelling along riverbanks in ravines, on bare earth All Himalayas, southern India and Sri Lanka in 8,2,20,35, 29, 30, 31, 2, 18, 21, 22, 23 HawaiiUSA:AlabamaFloridaGeorgiaHawaiiL 21 1938 2012 74 Naturalised (Vernon, 2013) Widespread on all islands ‐ also supported Wilson, 1996 banks near streams on moist shady rocks the west to western and southern China by CABI Vernon 2013 Dicksonia fibrosia Col. Wooly Tree fern Dicksoniaceae Naturalised Sexual Ground‐dwelling Occurs under tall mānuka and kānuka SS New Zealand 35 Northern New ZealandHawaii 35 1969 2017 48 Naturalised Not aggressive ‐ no serious spread but http://www.nzflora.info/factsheet/taxon/ scrub on forest margins or in podocarp likely originated from cultivated sources in Dicksonia‐fibrosa html Dicksonia squarrosa Rough tree fern Dicksoniaceae Invasive Both Ground‐dwelling Coastal montane forests All New Zealand 35 New Zealand 35 2010 2010 0 Native invasive species Source explanation Robinson et al. 2010 Dicranopteris linearis Gleicheniaceae Invasive Both All Species' most common habitat was open‐ Sun‐SS Old world tropics 23, 24, 25, 26, 27, 31 Malaysia 18 2010 2010 0 Problem fern Reports of dense stands Robinson et al. 2010 canopy (25‐60% cover) wet forests with Africa South and Southeast Asia and Dicranopteris linearis Gleicheniaceae Invasive Both All Species' most common habitat was open‐ Sun‐SS Old world tropics 23, 24, 25, 26, 27, 32 Sri Lanka 16 2010 2010 0 Problem fern Reports of dense stands Robinson et al. 2010 canopy (25‐60% cover) wet forests with Africa South and Southeast Asia and Dicranopteris linearis (Burm. f.) Underw. Old world forked fern Gleicheniaceae Naturalised Both All Species' most common habitat was open‐ Sun‐SS Hawaii, Africa ,east south africa, Asia, New 21,7,12,10,11,2,8,35,20 Brazil (SE)Hawaii 26 1904 2017 113 Adventive Reliable source definitions https://worldplants.webarchiv.kit.edu/fer canopy (25‐60% cover) wet forests with Zealand ‐ North Polynesia (https://www gbif org/occurrence/search ns/ Diplazium esculentum (Retz.) Sw. Athyrium esculentum (Retz.) Copel. Vegetable fern Athyriaceae Naturalised Both Ground‐dwelling Sun‐SS South‐eastern Asia 2 Azores 5 1953 2017 64 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ aliens org/speciesFactsheet do?speciesId= Diplazium proliferum (Lam.) Thouars Asplenium proliferum Lam. Mothers fern Athyriaceae Introduced Both Ground‐dwelling Denser forest, Raphia thickets and SS‐Shade Tropical Africa, Madagascar, Mascarene 10, 12, 15, 2, 8, 18, 19, 20, 21, 22 Trinidad and Tabago 25 2000 2000 0 Introduced no further information documenting Baksh‐Cameau, 2000 marshes Islands Asia Pacific Islands spread Diplazium esculentum (Retz.) Sw. Athyrium esculentum (Retz.) Copel. Edible fern Athyriaceae Invasive Both Ground‐dwelling Disturbed areas, exposed or in partial Sun‐SS South‐eastern Asia 2 HawaiiAustraliaSouth AfricaZimbabweFlori d21 1910 2012 102 Naturalised (Vernon, 2013) Clearly widespread Wilson, 1996 shade but always in wet sites such as Vernon 2013 Doodia caudata (Cav.) R. Br. Small rasp fern Blechnaceae Invasive Apogymous Ground‐dwelling seasonally moist earth banks, roadside All Australia, New Zealnd 29, 30, 31, 35, 37 South Africa:Eastern CapeKZNAzoresMadei 11 1985 2011 116 Invasive Initially only in a few locations in KZN but Crouch, 2011 Lithophyte cutting and forest margins shelterd inside has spread beyond the source within KZN Bothalia/ Crouch (2010) Doodia kunthiana Gaudich. Kunth's Hacksaw fern Blechnaceae Invasive Apogymous Ground‐dwelling Disturbed woods of the lower and dryish All Hawaii 21 Hawaii 21 1950 1950 0 Native weedy plant Invasive behaviour Wagner, 1950 Lithophyte gulches Dryopteris cycadina (Franch. et Sav.) Shaggy shield fern Dryopteridaceae Naturalised Both Ground‐dwelling SS‐Shade northern India, China, Taiwan and Japan 16,2,8 New Zealand 35 2003 2017 14 Naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as C Chr spread px?ID=4164 Dryopteris inaequalis (Schltdl.) Kuntze Dryopteridaceae Naturalised Both Ground‐dwelling forest floors and along forest margins, All tropical and southern Africa to 7,10,12,11,13,28,15 New Zealand 35 2003 2017 14 Naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as base of moist rock overhangs Madagascar spread px?ID=4165 Dryopteris ludoviciana Louisiana log fern Dryopteridaceae Naturalised Sexual Ground‐dwelling Southeastern United States 3 Arkansas 3 1982 1985 3 Naturalised Might be invasive because they speak of Peck, 1985 range expansion ‐ but this is very slowly Dryopteris oreades Mountain male fern Dryopteridaceae Naturalised Sexual Ground‐dwelling well‐drained rocky ledges, steep, loose Sun Britain and Ireland 1 Germany 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ scree slopes and in gullies Substrates aliens org/speciesFactsheet do?speciesId= Dryopteris X australis Southern woodfern Dryopteridaceae Naturalised Sexual Ground‐dwelling Southeastern United States 3 Arkansas 3 1927 1985 58 Naturalised Might be invasive because they speak of Peck, 1985 range expansion ‐ but this is very slowly Dryopteris affinis Fraser‐Jenk. Scaly male fern Dryopteridaceae Invasive Apogymous Ground‐dwelling deciduous woodland, along rides in SS‐Shade Europe, Asia 1, 2, 8 New Zealand 35 1980 2017 37 Adventive Widespread weedy fern of mostly easterly Brownsey, 1985 coniferous plantations in ditches on (http://www nzpcn org nz/flora details as parts of New Zealand Dryopteris dilatata (Hoffm.) A. Gray Broad buckler fern Dryopteridaceae Introduced Sexual Ground‐dwelling deciduous and coniferous woodland, SS Europe 1 northwest west FalklandEuropeNew Zealan33 1909 2003 94 Introduced and very rare Local ‐ has not spread Broughton, 2003 hedgerows ditches open moorland rocky http://www brc ac uk/plantatlas/plant/dr Dryopteris filix‐mas (L.) Schott Male fern Dryopteridaceae Introduced Apogymous Ground‐dwelling woodlands, hedgerows, ditches, roadside Sun Europe 1 northwest west FalklandNew Zealand 33 1911 2003 92 Introduced and very rare no further information documenting Broughton, 2003 Epiphyte verges stream banks rocky hillsides cliff spread Brownsey 1985 Equisetum arvense L. Field horsetail Equisetaceae Invasive Both Ground‐dwelling river banks, fixed dune grassland, sea‐cliffs Sun Circumpolar Wide‐boreal element. 1,8,2,3,4 New ZealandAzoresAustralia 35 1920 1985 65 Adventive Clearly spreading Brownsey, 1985 and montane flushes but it has become http://www europe‐ Equisetum fluviatile L. Water horsetail Equisetaceae Naturalised Both Ground‐dwelling along freshwater shorelines or in shallow Sun Temperate northern hemisphere ‐ 1,4,3,9,5,6,7,8,2 New Zealand 35 1988 2017 29 Naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as Swamp horsetail water in ponds swamps ditches and widespread spread px?ID=4146 Equisetum hyemale L. Rough horsetail Equisetaceae Invasive Both Ground‐dwelling mesic (reliably moist) habitats, often in Sun‐SS Temperate northern hemisphere ‐ Europe, 1,4,3,9,8,2 New Zealand 35 1993 2017 24 Naturalised Aggressive and almost impossible to http://www.nzpcn.org.nz/flora_details.as sandy or gravelly areas wetlands and in Asia North America erradicate px?ID=4114 Equisetum variegatum Schleich. Variegated horsetail Equisetaceae Naturalised Both Ground‐dwelling wide variety of habitats, including dune‐ Sun North ‐ Europe, Asia, America 1,8,2,3,4 Faroe Islands, Sweden 1 2017 0 Alien ‐ established, not invasive Description of éstablished'meets criteria http://www.europe‐ slacks river shingle upland flushes and aliens org/speciesFactsheet do?speciesId= Equisetum arvense Field horsetail Equisetaceae Invasive Both Ground‐dwelling Disturbed areas such as pastures, Sun Circumpolar Wide‐boreal element. 1,8,2,3,4 Britain and Ireland 1 2010 2017 7 Native invasive species it is now frequent on roadsides, railways, Robinson et al. 2010 roadsides etc paths soil banks and waste ground and in http://www brc ac uk/plantatlas/plant/eq Equisetum palustre L. Marsh horsetail Equisetaceae Fuzzy Both Ground‐dwelling marshes, damp pastures, ditches, dune‐ Sun cooler regions of North America and 1,8,2,3,4 BulgariaAndorra 1 2017 0 Alien ‐ unknown insufficient information http://www.europe‐ slacks streams rivers and mountain Eurasia aliens org/speciesFactsheet do?speciesId= Equisetum ramosissimum Desf. Branched horsetail Equisetaceae Naturalised Both Ground‐dwelling rough grassland near the sea, on sand or Sun Eastern hemisphere ‐ S, E and 7, 12, 10, 11, 28, 13, 1, 2, , 17, 18, 15, 23, Brish Isles:UkraineBulgariaEnglandUnited S1 1880 1978 98 Alien ‐ unknown poulation localised ‐ but still in existance Jermy, 1978 clay soil Lowland Mediterranean Africa the Canary and 24 25 26 27 Neophyte (self‐sustaining) http://www europe‐ Equisetum telmateia Great horsetail Equisetaceae Invasive Both Ground‐dwelling base‐rich clay soils in sites with spring‐ Sun Africa, Asia (temperate), Europe, North 1, 2, 8, 7, 12, 3, 4 USA 3,4,9 2010 2010 0 Native invasive species Colony forming and "This species has Robinson et al. 2010 lines permanent seepages and open USA apparently become more frequent in Gleichenia dicarpa Pouched coral fern Gleicheniaceae Invasive Both Ground‐dwelling under waterfalls, in swamps, under cliffs Sun Eastern Australia, New Zealand 29, 35 New Zealand 35 2010 2010 0 Native invasive species Dense coloniser Robinson et al. 2010 and in tall open forest Gleichenia japonica Koshida Gleicheniaceae Invasive Both Ground‐dwelling well drained, yet moist hillsides in both sun All Japan 2 Japan 2 2010 2010 0 Native invasive species Dense coloniser Robinson et al. 2010 and shade often seen in tree plantations Gleichenia pectinata Gleicheniaceae Invasive Both Ground‐dwelling All New world tropics 3, 4, 9, 25, 26, 27, 33 New world tropics 3, 4, 9, 25, 26, 27, 33 2010 2010 0 Native invasive species Dense coloniser Robinson et al. 2010

Hemionitis tomentosa (Lam.) Raddi Gymnopteris tomentosa (Lam.) Underw. Pteridaceae Naturalised Ground‐dwelling Tropical rain forest Brazil and West Indies 23, 26 Sri Lanka 16 1982 2009 27 Introduced Alien no further information documenting Sledge, 1982 Adventive and very common in India spread FernGaz 2009 Histiopteris incisa Dennstaedtiaceae Invasive Ground‐dwelling Wet forest, scrubby creeks and gullies and SS‐Shade Australia, New Zealand and Southern Queensland, Tazmania and New Zealand 29,30,31,35 2010 2010 0 Native invasive species Likely invasive due to description of Robinson et al. 2010 at the base of cliffs hemisphere behaviour and occurance Hypolepis muelleri Dennstaedtiaceae Invasive Ground‐dwelling East Australia 29 West Australia 30, 31 2010 2010 0 Native invasive species Likely invasive due to description of Robinson et al. 2010 behaviour and occurance Hypolepis rugosula Dennstaedtiaceae Invasive Ground‐dwelling disturbed areas at the sides of roads and Sun‐SS Southern hemisphere Southeastern and southwestern Australia 29, 30, 31 2010 2010 0 Alien ‐ problem fern Likely invasive due to description of Robinson et al. 2010 tracks behaviour and occurance Lindsaea ensifolia Sw. Graceful necklace fern Lindsaeaceae Naturalised Sexual Ground‐dwelling Confined to low altitude forest, usually in All Africa, India, Pacific (Malesia to west 18. 12, 11, 16, 2, 15 Hawaii 21 1969 2013 44 Naturalised (Vernon, 2013) Appears to be limited to a select few Wilson, 1996 Epiphyte coastal swamp forest growing on boggy Melaneisa) Southern Asia Madagascar locations ‐ not spreading Vernon 2013 Lygodium flexuosum (L.) Sw. Lygodiaceae Invasive Sexual Ground‐dwelling Semi‐dry and moist forest or woodland All Asia, Australia 2,8,29,30,31 Venezuela 25 2017 0 Adventive ‐ widespread widespread, aswell as behaviour https://worldplants.webarchiv.kit.edu/fer Epiphyte areas ns/ Lygodium microphyllum Old world climbing fern Lygodiaceae Invasive Sexual Ground‐dwelling common in cypress stands, but also infests All Tropical regions of Africa, Asia, Australia 10,12,7,2,8,29,30,31,18,19,20,21,22 USA:Broward CountyFloridaHighlands coun 3 1966 (Volin, 2004) 2017 51 Invasive (Cat 1) Reliable source definitions Lott, 2003 Epiphyte pine flatwoods wet prairies sawgrass and the Pacific Islands (Boughton 2009) Volin 2004 Lygodium venustum Lygodiaceae Invasive Sexual Ground‐dwelling Dry disturbed All South and central America, Caribbean 23,24,25,26,27 Mexico 23 2010 2010 0 Native invasive species Likely invasive due to description of Robinson et al. 2010 Epiphyte behaviour and occurance Lygodium japonicum (Thunb.) Sw. Japanese climbing fern Lygodiaceae Invasive Sexual Ground‐dwelling moist or, and in various disturbed sites All Eastern Asia 2, 8 North, Central, South FloridaHawaiiUSA:Al a 3 1903 2017 114 Invasive (Cat 1) Reliable source definitions FLEPPC. 2017. List of Invasive Plant Epiphyte such as yards and roadsides It is often Species Florida Exotic Pest Plant Council Macrothelypteris torresiana (Gaudich.) Lastrea torresiana (Gaudich.) T. Moore Torres' Fern Thelypteridaceae Naturalised Sexual Ground‐dwelling On banks or on disturbed soil in forest Shade Tropical Asia, Africa (Mauritius), Samoa, 2, 15, 18, 29, 31, 30 Trinidad and TabagoSouth Africa:KZNEaste r 25 1828 2000 172 Introduced and Naturalised no further information documenting Baksh‐Comeau, 2000 Ching Polystichum torresianum Gaudich areas and on rocky stream sides Tahiti and tropical Australia spread Crouch 2011 Matteuccia struthiopteris (L.) Tod. Ostrich fern Onocleaceae Naturalised Both Ground‐dwelling Riverbanks and sandbars Sun‐SS North ‐ Europe, Asia, America 1, 2,8,3,4,9 British Isles 1 1978 2017 39 escaped and established no further information documenting Jermy, 1978 spread https://www gbif org/occurrence/search? Microlepia platyphylla (D. Don) J.E. Sm. Plate fern Dennstaedtiaceae Naturalised Both Ground‐dwelling Moist stream banks SS‐Shade India, Asia, phillipines 16,1,8,18 Madeira 5 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ aliens org/speciesFactsheet do?speciesId= Microlepia strigosa (Thunb.) C. Presl Davallia strigosa Scented Fern Dennstaedtiaceae Invasive Both Ground‐dwelling Disturbed woods of the lower and dryish Sun‐SS Southeast Asia and Hawaii 2, 21 HawaiiZimbabwe 21 1950 1950 0 Native weedy plant Invasive behaviour ‐ dense stands Wagner, 1950 Lace Fern gulches Roux 2009 Microsorum scandens Tindale Phymatosorus scandens (G. Forst.) C. Presl Fragrant fern Polypodiaceae Introduced Both All In close proximity to streams. Coastal to Shade Australia 29,30,31,35 South Africa: Cape townZimbabwe 28 1944 2017 73 Introduced One escapee, no further documentation Crouch, 2011 lowland in forest Microsorum scandens is New Zealand (https://www gbif org/occurrence/search of population or spread Nephrolepis brownii (Desv.) Hovenkamp & Asian sword fern Nephrolepidaceae Invasive Both Ground‐dwelling Most Nephrolepis species grow in thickets Sun South East Asia 2, 35 Central, South FloridaPeurto RicoHawaiiCe n3 1940 2017 77 Invasive (Cat 1) Reliable source definitions FLEPPC. 2017. List of Invasive Plant Miyam (Holttum 1938) preferring acidic humus New Zealand Species Florida Exotic Pest Plant Council Nephrolepis cordifolia (L.) C. Presl Tuberous sword fern Nephrolepidaceae Introduced Both Ground‐dwelling found naturalized in pine rocklands, All Australia 29, 30, 31 Trinidad and TabagoMadagascarReunion Isl 25 1908 2017 109 Introduced ‐ common in cultivation Not reported outside of cultivation Baksh‐Comeau, 2000 Epiphyte flatwoods marsh edges and hammocks (https://www gbif org/occurrence/search https://www gbif org/occurrence/search? Nephrolepis exaltata (L.) Schott Southern sword fern Nephrolepidaceae Naturalised Both Ground‐dwelling along forest margins and on dry and SS‐Shade Unknown Mexico Trinidad and TabagoSouth AfricaTa n23 1854 (GBIF) 2017 163 Naturailsed no further information documenting Baksh‐Comeau, 2000 Epiphyte exposed road cuttings spread CARA invasive plants list Nephrolepis falcata (Cav.) C. Chr. Fishtail fern Nephrolepidaceae Invasive Both Ground‐dwelling SS‐Shade Australia 29,30,31 Hawaii 21 1936 2013 77 Locally common Spread beyond source Wilson, 1996 Epiphyte Vernon 2013 Nephrolepis hirsutula (G. Forst.) C. Presl Scaly sword fern Nephrolepidaceae Naturalised Both Ground‐dwelling Dry ground Sun‐SS Asia 2,8 Hawaii 21 1983 2013 30 Naturalised, common Between Wilsons papers of 96 and 2000 it Wilson, 1996 has not spread into new areas and is also Vernon 2013 Nephrolepis multiflora (Roxb.) F.M. Jarrett Asian sword fern Nephrolepidaceae Naturalised Both Ground‐dwelling in thickets and open ground, also on cliffs Sun‐SS India and tropical Asia 16,2,8,11,12,9 HawaiiFloridaPeurto RicoAn llestropical So 21 1923 2000 77 Naturalised no further information documenting Wilson, 2000 ex CV Morton and old walls spread Baksh‐Comeau 2000 Nephrolepis biserrata (Sw.) Schott Fishtail fern Nephrolepidaceae Invasive Both Ground‐dwelling Terrestrial, in swampy ground and SS‐Shade Florida, Mexico, the West Indies, Central 3,23,24,25,26,27,2 Hawaii 21 1936 1950 14 Locally abundant Gorws gregariously in various places on Wagner, 1950 permanently moist conditions occuring in America South America Africa and the island Onoclea sensibilisL. Sensitive fern Onocleaceae Naturalised Sexual Ground‐dwelling wet swamp and wood habitats: wet SS‐Shade East Russia, China, Eastern Asia, Northern 1,8,2,3,4,9 Brish IslesNew Zealand 1 1978 2017 39 escaped and established no further information documenting Jermy, 1978 Bead fern meadows thickets and bogs as well as America spread http://www europe‐ Onychium japonicum (Thunb.) G. Kunze Pteridaceae Naturalised Ground‐dwelling Stream banks, roadsides, forest margins, Shade Asia 2,8 Azores 5 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ mountain slopes aliens org/speciesFactsheet do?speciesId= Ophioglossum costatum R. Br. Large adders tongue Ophioglossaceae Naturalised Both Ground‐dwelling On seasonally moist, shallow soils, on sand SS southern and tropical Africa, Madagascar, 10,11,12,13,28,15,16,29,30,31 Trinidad 25 2017 0 Adventive Reliable source definitions https://worldplants.webarchiv.kit.edu/fer overlying rocks at the edge of pans in India and Australi ns/ Ophioglossum pendulum L. Ophioderma pendulum (L.) Presl Old world adders tongue Ophioglossaceae Naturalised Sexual Epiphyte growing on palms, tree‐ferns, trees, Sun‐SS Oceania, Madagascar, Asia, Hawaii 18,20,29,30,31,2,8,15,21 Florida 3 1998 2017 19 Adventive no further information documenting https://worldplants.webarchiv.kit.edu/fer sometimes on rocks; in the lowlands and (http://florida plantatlas usf edu/Plant as spread ns/ Ophioglossum reticulatum L. Stalked Adder's‐tongue Ophioglossaceae Naturalised Both Ground‐dwelling Moist sandy soils, seasonally wet soils, Sun‐SS Asia, South and Tropical Africa, Pacific 2,8,12,10,11,13,18,23,24,25,26,27,33 USA:AlabamaArkansasFloridaGeorgiaLouisi a3 2017 0 Adventive no further information documenting https://worldplants.webarchiv.kit.edu/fer along roads on termite hills in montane Islands Central and South America spread ns/ Osmunda regalis L. Osumundaceae Naturalised Sexual Ground‐dwelling always grows near water, along rivers and Sun Europe, North, Central and South America, 1,3,4,9,23,24,25,26,27,2,8,7,10,12,11,15,16New Zealand 35 1890 2017 127 Adventive Well established but not spreading ‐ also Brownsey, 1985 streambanks where the rhizome is Asia Africa Madagascar and the (http://nzpcn org nz/flora details aspx?ID the term adventive Paesia scaberula Ring fern Dennstaedtiaceae Invasive Sexual Ground‐dwelling Coastal to montane. An often common Sun New Zealand 35 New Zealand 35 2010 2010 0 Native invasive species Serious pest Robinson et al. 2010 fern of open or distrubed ground rough Pellaea ternifolia (Cav.) Link Pteridaceae Naturalised Sexual Ground‐dwelling Terrestrial, in dry open areas, but also Sun America 3,4,9 Hawaii 21 1982 1982 0 Adventive The term adventive refers to a population Tyron & Tyron, 1982 Lithophyte occurring in shaded gullies Rocky slopes akin to casual/ established ‐ but not Pellaea viridis (Forssk.) Prantl Pteridaceae Introduced Sexual Ground‐dwelling Dry, rocky, grassly slopes above the rail at Sun Africa, Yemen, some Pacific Ocean islands 7, 10, 13, 14, 12 Sri LankaNew ZealandHawaii 16 1982 2017 67 Introduced Alien no further information documenting Sledge, 1982 Lithophyte Pohakea Pass and India spread Phlebodium aureum (L.) J. Sm. Golden polypody Polypodiaceae Naturalised Both All Moist wooded areas ‐ coastal or inland Sun‐SS Central America from Florida and Georgia 3, 23, 24, 25, 26, 27, 33 HawaiiSouth Africa: KZN & Eastern Cape Zim21 1909 2012 103 naturalised (Vernon, 2013) no further information documenting Wilson, 1996 Golden serpent fern in the USA through Mexico to Brazil in spread Vernon 2013 Phymatosorus grossus (Langsd. & Fisch.) Maile‐Scented fern Polypodiaceae Naturalised Both Ground‐dwelling Forested areas SS Australia and New Caledonia to Fiji and Hawaii 21 1919 2012 93 Naturalised no further information documenting Wilson, 2000 Brownlie eastward throughout the South Pacific spread Vernon 2013 Phymatosorus diversifolius (Willd.) Pic. Microsorum pustulatum (G.Forst.) Copel. Kangaroo paw fern Polypodiaceae Naturalised Both Ground‐dwelling growing over rocks or fallen logs, on cliffs SS New Zealand, Australia 29,30,31 Europe 1 2017 0 Alien ‐ established etablished population but not spreading ‐ http://www.europe‐ Serm Epiphyte and banks or epiphytic on native and more casual aliens org/speciesFactsheet do?speciesId= Phymatosorus scolopendria (Burm. f.) Pic. Microsorum scolopendria (Burm. f.) Copel. Serpent fern Polypodiaceae Invasive Both All Primary Rainforest; Agricultural Land; SS‐Shade Africa, Sri Lanka, Southern China, South 7,12,10,11,2,8,29,30,31,20,22,19,21,23 Florida (South Florida)Trinidad and TabagoV 9 1900 (GBIF) 2017 117 Not listed as naturalised ‐ but Possley Category 1 FLEPPC ‐ more like a Possley, 2004 Serm Wart fern Secondary Rainforest; Coastal Forest; East Asia Australia and Polynesia states that it is worrisome and should be transformer Pityrogramma calomelanos (L.) Link Gymnogramma calomelanos var. Golden Fern Pteridaceae Naturalised Sexual Ground‐dwelling earthbanks along roads, culverts and Sun‐SS South and Central America 23, 24, 25, 26, 27, 33 HawaiiSri LankaAzoresMadeiraUSASouth Af21 1903 2013 110 Frequent to abundant throughout the Definitions match Wagner, 1950 aureoflava Hook Lithophyte ditches usually disturbed habitats islands Wilson 1996 Pityrogramma calomelanos var. Pityrogramma austroamericana Domin. Goldfern Pteridaceae Naturalised Sexual Ground‐dwelling earthbanks along roads, culverts and Sun‐SS Central America 23 Hawaii 21 1903 2012 109 Naturalised no further information documenting Wilson, 2000 austroamericana (Domin) Farw Lithophyte ditches usually disturbed habitats spread Vernon 2013 Pityrogramma chrysophylla (Sw.) Link Island goldback fern Pteridaceae Introduced Sexual Ground‐dwelling earth banks, in and around the forest. All West Indies 23,24,25,26,27,33 Hawaii 21 2017 0 Introduced no further information documenting https://plants.usda.gov/core/profile?symb Lithophyte South America spread ol=PICH Pityrogramma ebenea (L.) Proctor Mountain silverback Pteridaceae Naturalised Sexual Ground‐dwelling Rocky slopes and banks All Andes and central america 23,24,25,27 Azores 5 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ aliens org/speciesFactsheet do?speciesId= Pityrogramma dealbata (C. Presl) Pteridaceae Introduced Sexual Ground‐dwelling Lowland forest All Central America 23 Sri Lanka 16 1926 (GBIF) 2017 91 Introduced Alien no further information documenting Sledge, 1982 spread Pityrogramma sulphurea (Sw.) Maxon Jamaican goldback fern Pteridaceae Introduced Sexual Ground‐dwelling earth banks, in and around the forest. All West Indies 23 Sri Lanka 16 1982 2017 35 Introduced Alien no further information documenting Sledge, 1982 spread GBIF Platycerium bifurcatum (Cav.) C. Chr. Common staghorn fern Polypodiaceae Invasive Sexual Epiphyte High‐level epiphyte on trees as well as All Australia 29,30,34, 31, 36,33,35 South FloridaHawaiiNew ZealandKZNMade i3 1886 (GBIF) 2017 131 Invasive (Cat 2) Category 2 ‐ defines as invasive but not FLEPPC. 2017. List of Invasive Plant engineered structures such as concrete yet transformer Species Florida Exotic Pest Plant Council Platycerium superbum Elkhorn fern Polypodiaceae Naturalised Sexual Epiphyte High‐level epiphyte on trees as well as All Australia 29,30,36 Hawaaiian Islands 21 2010 2012 2 naturalised (Vernon, 2013) no further information documenting Robinson et al. 2010 Staghorn fern engineered structures such as concrete spread Vernon 2013 Plenasium angustifolium A.E.Bobrov Osmundaceae Naturalised Sexual Ground‐dwelling Streams and hillsides SS Asia 2,8 Sri Lanka, India 16 2017 0 Adventive Reliable source definitions https://worldplants.webarchiv.kit.edu/fer ns/ Polypodium hesperium Maxon Western polypody Polypodiaceae Naturalised Sexual Lithophyte Rocky areas Shade Western North America, British Columbia, 4,9,27,23 Europe: Belgium 1 2017 0 Alien ‐ not established established population but not spreading ‐ http://www.europe‐ California Mexico more casual aliens org/speciesFactsheet do?speciesId= Polypodium vulgare L. Common polypody Polpodiaceae Naturalised Sexual Ground‐dwelling old walls, cracks in rocks, the bases of SS‐Shade Europe and Asia 1,2,8 New Zealand 35 1980 2017 37 Adventive The term adventive refers to a population Brownsey, 1985 Lithophyte trees and in rocky undergrowth It prefers (http://www nzpcn org nz/flora details as akin to casual/ established ‐ but not Polypodium australe Fée Polypodiaceae Fuzzy Sexual Lithophyte Rocky areas ‐ Coastak and lower Shade Europe 1 California 9 2007 2017 10 Non‐native insufficient information http://www.calflora.org/cgi‐ mountain bin/species query cgi?where‐ Polystichum aculeatum (L.) Roth ex Mert. Hard shield fern Dryopteridaceae Naturalised Both Ground‐dwelling Steep slopes in woodlands SS‐Shade Europe 1 Sweden 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ Lithophyte aliens org/speciesFactsheet do?speciesId= Polystichum lentum (D. Don) T. Moore Dryopteridaceae Naturalised Ground‐dwelling On rocks in montane broad‐leaved SS China 2,8 New Zealand 35 1985 2017 32 Adventive The term adventive refers to a population Brownsey, 1985 Lithophyte evergreen forests akin to casual/ established ‐ but not GBIF Polystichum lonchitis (L.) Roth Northern holly fern Dryopteridaceae Naturalised Sexual Ground‐dwelling Northern hardwood or mixed conifer‐ Sun‐SS Eurasia, Alaska, Greenland, Central North 1,3,4 Sweden, Denmark 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ Lithophyte hardwood forests over calcareous rock America aliens org/speciesFactsheet do?speciesId= Polystichum munitum (Kaulf.) C.Presl Western sword fern Dryopteridaceae Naturalised Both Ground‐dwelling understory of moist coniferous forests at Shade North America, Alaska, California 1,3,4,9 Great Britain 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ low elevations It grows best in a well‐ aliens org/speciesFactsheet do?speciesId= Polystichum polyblepharum (Roem. ex Tassel Fern Dryopteridaceae Naturalised Apogymous Ground‐dwelling Woodlands SS‐Shade Asia 2,8 New Zealand 35 2003 2017 14 Naturalised no further information documenting http://www.nzpcn.org.nz/flora_details.as Kunze) C Presl spread px?ID=4167 Polystichum proliferum R. Br. Mother shield fern Dryopteridaceae Naturalised Both Ground‐dwelling in amongst boulders and at lower SS‐Shade Australia 29,30,31 New Zealand 35 1890 2017 127 Adventive The term adventive refers to a population Brownsey, 1985 altitudes ‐ in wet forests [3] The species (http://www nzpcn org nz/flora details as akin to casual/ established ‐ but not Polystichum setiferum (Forsskal) Woynar Soft shield fern Dryopteridaceae Naturalised Ground‐dwelling SS‐Shade Europe 1 New Zealand 35 1891 2017 127 Adventive The term adventive refers to a population Brownsey, 1985 (http://www nzpcn org nz/flora details as akin to casual/ established ‐ but not Polystichum braunii (Spenn.) Fée Braun's holly fern Dryopteridaceae Naturalised Both Ground‐dwelling Forests, talus and rocky slopes SS‐Shade Europe 1,3,4,9 SwedenDenmark 1 2017 0 Alien ‐ established Description of éstablished'meets criteria http://www.europe‐ North America aliens org/speciesFactsheet do?speciesId= Psilotum nudumL. Grisebach Wisk fern Psilotaceae Invasive Both All Boles of coconut trees and rock walls, Sun‐SS Hawaii, Africa, Adscension Islands, Fiji, 21,7,12,10,11,13,28,15,18,14 HawaiiCanary Islands 21 1950 1950 0 Native weedy plant Clearly spreading Wagner, 1950 even in downtown honolulu Coastal to Madagascar https://worldplants webarchiv kit edu/fer Pteridium aquilinum (L.) Kuhn Pteridium aquilinum subsp. aquilinum Braken fern Dennstaedtiaceae Invasive Both Ground‐dwelling Disturbed montane forests and wet Sun‐SS Temperate and sub‐tropical regions in South Africa (Eastern and South)JamaicaBa 11,28,12 1772 (GBIF) 2010 238 Invasive Invasive behavious and difficulty to Crouch, 2010 grasslands wet sandly flast beside lagoos both hemispheres control https://www cabi org/isc/datasheet/4559 Pteridium aquilinum subsp. decompositum Dennstaedtiaceae Invasive Both Ground‐dwelling Along the borders of pineapple fields near Sun‐SS Hawaii 21 Hawaii 21 1950 1950 0 Native weedy plant Invasive behavious and difficulty to Wagner, 1950 (Gaudich ) uncultivated thickets mesic to wet control Pteris cretica L. Cretan brake Pteridaceae Invasive Apogymous Ground‐dwelling mainly on disturbed and modified sites SS‐Shade Europe, Asia and Africa Eastern and 1,2,8,12,11,28 USA (Florida, California)New ZealandUKBri 3 1779 (GBIF) 2017 238 Invasive Reliable source definitions http://www.calflora.org/cgi‐ Ribbon fern such as waste ground road and trail sides Southern bin/species query cgi?where‐ Pteris dentata subsp. flabellata (Thunb.) Toothed brake Pteridaceae Naturalised Ground‐dwelling base rich substrates such as basalt rock, SS‐Shade South Africa 11,12,28 New Zealand 35 1979 2017 38 Naturalised no further information documenting http://www.nzflora.info/factsheet/taxon/ Runemark basalt stone and/or concrete walls in spread Pteris‐dentata‐subsp‐flabellata html Pteris multifida Poir. Spider brake Pteridaceae Naturalised Both Ground‐dwelling Inland and coastal forested areas , near Shade Asia 2,8 Eastern North Americaform Florida Northw3 1874 (GBIF) 2017 143 Naturalised a small population not spreading Peck, 1985 Lithophyte streams and freshwater systems ‐ rocky Chandler 1941 Pteris pacifica Hieron Pteridaceae Naturalised Sexual Ground‐dwelling SS Australia (north‐eastern Queensland), 29,18 New Zealand 35 1999 2017 18 Naturalised Reliable source definitions http://nzpcn.org.nz/flora_details.aspx?ID= Malesia and the South Pacific Islands 4159 Pteris tremula R.Br. Shaking brake Pteridaceae Invasive Both Ground‐dwelling Coastal to montane (in northern part of SS Australia, New Zealand and the Fiji Islands 29,30,31,35,19 South AfricaWestern CapeEastern CapeKZ N 11, 28 1875 (GBIF) 2017 142 Invasive (Baard & Kraaij, 2014) Reliable source definitions Crouch, 2011 Tender brake range) in open dry forest scrub https://www itis gov/servlet/SingleRpt/Sin Pteris tripartita Sw. Giant brake Pteridaceae Introduced Both Ground‐dwelling Roadside banks and in thickets and SS‐Shade Polynesia, Indonesia and Africa 20,17,7,10,12 Trinidad and TabagoUS ‐ Lower 48 statesJa m25 1918 (GBIF) 2017 99 Introduced ‐ rare rare, and does not seem to be evidently Baksh‐Comeau, 2000 sheltered ravines wet flatwoods cattail spreading https://plants usda gov/core/profile?symb Pteris vittata L. Chinese brake Pteridaceae Naturalised Both Ground‐dwelling Shaded waste ground, crevices of walls or All South America, Asia, Africa and Australia 24, 25, 26, 27,33,2,8,29,30,31, Trinidad and TabagoHawaiiAn llesPeruNor t25 1861 (GBIF) 2017 156 Inroduced ‐ common Populations in wild but no evidence of Baksh‐Comeau, 2000 Ladder brake cliffs Cracks in bridges 11121097131415 spread Wagner 1950 Pteris x delchampsii Pteridaceae Invasive Ground‐dwelling Sun‐SS Florida ‐ hybrid 3 Florida 3 1950 2000 50 Invasive Almost always occurs with P. vittata Possley, 2000

Pteris ensiformis Burm. f. Silver lace fern Pteridaceae Naturalised Both Ground‐dwelling Wet, acidic soils in forests, stream margins SS Asia, Malaysia and Polynesia 2,8,18,20 JamaicaPeurto rico 23 1847 (GBIF) 2017 170 Adventive The term adventive refers to a population Tyron & Tyron, 1982 Slender brake akin to casual/ established ‐ but not https://plants usda gov/core/profile?symb Pyrrosia piloselloides Polypodiaceae Naturalised Epiphyte They occur everywhere on the trunks of Sun‐SS China, India and Melesia 2,8,16,18 Hawaii 21 2013 0 Naturalised no further information documenting Vernon, 2013 old trees including mangroves spread Rumohra adiantiformis (Forster) Ching 7 week fern Dryopteridaceae Naturalised Both Ground‐dwelling Shaded forest floors and forest margins, SS‐Shade South America, the Caribbean, southern 24,25,26,27,33,23,11,12,28,18,29,30,31 Belgium ‐ Europe 1 1886 2017 131 Alien ‐ not established etablished population but not spreading ‐ http://www.europe‐ rocky slopes and more rarely on boulder Africa the Western Indian Ocean islands more casual aliens org/speciesFactsheet do?speciesId= Sphaeropteris cooperi Alsophila cooperi F. Muell. Australian tree fern Cyatheaceae Naturalised Sexual Ground‐dwelling The native habitat is in gullies and SS Northeastern Australia ‐ Queensland 29; 31 Western Australia (Bedfordale)South Easter30,31 1942 2010 68 Naturalised No evidence of spread Robinson et al. 2010 Cyathea cooperi (F Muell ) Domin rainforests It can also be found along Sphaeropteris cooperi (F. Muell.) R.M. Alsophila cooperi F. Muell. Cooper's tree fern Cyatheaceae Naturalised Sexual Ground‐dwelling The native habitat is in gullies and SS Australia 29; 30; 31 California (los Angeles)HawaiiMauri usReu 9 1919 (GBIF) 2017 98 Naturalized large but single population http://www.calflora.org/cgi‐ Tryon Cyathea cooperi (F Muell ) Domin rainforests It can also be found along bin/species query cgi?where‐ Sphenomeris chinensis (L.) Maxon Lindsaea chinensis (L.) Mett. ex Kuhn Pala'a fern Lindsaeaceae Fuzzy Both Ground‐dwelling Disturbed areas and higher forests ‐ SS Hawaii 21 Hawaii 21 1950 1950 0 Native weedy plant Invasive behaviour but not necessarily Wagner, 1950 Microlepia chinensis (L ) Mett covering dirt banks along some roads and invasive ‐ weedy Tectaria incisa Cav. Aspidium macrophyllum Sw. Incisedhalbard fern Tectariaceae Invasive Both Ground‐dwelling Forests, Rocky hammocks SS‐Shade Caribbean and Tropical America 23, 24,25,26,27,33 FloridaMiami ‐Dade county (Possley, 2013)H 3 1970 2017 47 Naturalised Category 1 FLEPPC ‐ more like a Possley, 2004 Lithophyte transformer FLEPPC Thelypteris kunthii (Desv.) C.V. Morton Southern Shield fern Thelypteridaceae Invasive Both Ground‐dwelling Woodlands, streambanks, swamps, ditches SS‐Shade Southerneastern United States 3,4 Arkansas 3 1979 1985 6 Extra‐limital establishement of new populations some Peck, 1985 distance from source Woodwardia radicans (L.) Sm. Blechnum radicans L. Chain fern Blechnaceae Naturalised Both Ground‐dwelling Moist forested areas SS‐Shade Atlantic islands and North West Europe 5,1 Algeria 7 2009 2009 0 Naturalised no further information documenting Roux, 2009 spread Number of introduced regions Residence Time Number of native kindoms Residence Time 0.449 Number of native kindoms 0.190 0.162 Number of native regions 0.058 0.067 0.755