Spread Of Alien Plant Species Research Articles

Additions to the flora of Northwestern European Russia

The article presents new data on vascular flora of the North-West of the European part of Russia. The data are based on our field surveys in 2021–2023, revision of herbarium collections and searching data in open sources. In the Leningrad Region, we recorded four alien species new to the Northwestern European Russia, namely Linum nervosum Waldst. et Kit., Phytolacca acinosa Roxb., Dipsacus laciniatus L., and Viscum album L., and one species new to St. Petersburg (Rhynchospora fusca (L.) W.T. Aiton), a nationally rare and protected native. The results of the study show, on the one hand, the need for further research in the region, and on the other hand, the ongoing spread of alien plant species across European Russia.

Invasive plant species and their threat to biodiversity

The problem of the uncontrolled spread of alien plant species matured in the world in the second half of the 20th century, and in recent decades it has become the main threat to the biological diversity of various regions of the world. Prevention of biological Invasions is a new urgent task in the field of nature protection, which determines the relevance of the study. The purpose of the study is to determine and predict the distribution area of invasive plants, based on the use of the following methods: comparative morphological-ecological-geographical, route using determinants and atlases of plants of Ukraine, and the method of structural analysis. It is established that the characteristic features of invasive plant species are very high tolerance to habitat and climatic conditions, high rate of reproduction, simple and effective distribution by wind, water, animals, and rapid growth, which contributes to the displacement of slow-growing plants of other species and uncontrolled spread in the absence of natural enemies and restrictions. A particular danger to the biodiversity of Ukraine is the spread of invasive plant species: Sosnowsky’s Hogweed (Heracleum sosnowskyi), Canadian Goldenrod (Solidago canadensis L), American maple (Acer negundo L.), Red Oak (Quercus rubra), Common Ragweed (Ambrosia artemisiifolia L.), Common Milkweed (Asclepias syriaca L.), Silver Berry (Elaeagnus angustifolia), American pokeweed (Phytolacca Americana), Ecballium (Ecballium elaterium), Common Sandbur (Cenchrus pauciflorus Benth), Wall Barley (Hordeum murinum L.), Jerusalem Artichoke (Helianthus tuberosus), etc. The results of the study are an important scientific and practical basis for developing national and regional strategies for controlling invasive plant species

Non-Native Plants Species and Biodiversity of Socotra Island, Yemen

Socotra Island has significant ecological and economic importance at local, national and global scales. Invasive plant species are often considered as potential competitors of native species due to their usual greater capacity for colonization and expansion. The spread of alien plant species has long been recognized as one of the most significant environmental changes due to its ability to decrease biodiversity and alter ecosystem processes. In areas with homogeneity population of wild invasive species especially Argemone mexicana, 32 random sites were randomly detected. Ninety six Quadrates plots were laid down to study the interaction between the invasive plant and the native species especially with conservation attention of endemic plant species. The main aims is to provide base informatics data to establish comprehensive habitat surveillance programs to enable early detection and rapid response of IAS, prevent both intentional or accidental introductions of harmful invasive alien species to the Socotra Island and reduce the likelihood of alien species invasions by decreasing stresses on vulnerable at-risk ecosystems and species. This study was conducted to identify the different types of invasive species present, the rate and pattern of invasion, its intensity, association of invaders and their habitat preference in the Socotra ecosystem. Vegetation sampled in 96 quadrats, each 10 m _ 10 m; through a combination of random and systematic sampling recorded 42 plant species of 36 genera belonging to 24 families with around 10% was recorded as invasive species. Diversity indices like richness, evenness, Simpson and Shannon-Wiener have been analyzed.

The flora of pine forests of the vicinity of Hrafske village (Vovchansk District, Kharkiv Region)

The article presents the results of a study of the flora of pine forests in the vicinities of the villages Hrafske, Verkhnia Pysarivka, and Symonivka of the Vovchansk District of the Kharkiv Region. The flora of the investigated area includes at least 120 species of vascular plants of 47 families, five classes, and four divisions. The richest in the flora are the families Asteraceae (22 species; 18.3%), Poaceae (13 species; 10.8%), and Caryophyllaceae (10 species; 8.3%) that are characteristic of the pine forests of the Kharkiv Region. The presence of Crassulaceae (5 species; 4.2%) at the fifth position in the spectrum of dominating families is due to anthropogenic impact on the vegetation of the study area. Analysis of the flora ecological structure by three main abiotic factors (soil water regime, total salt regime, and light) has shown the typical conditions of the valley forests of the Kharkiv Region with a predominance of mesophytic and submesophytic (84 species; 70%), semieutrophic (64 species; 52.9%) and subheliophytic (88 species; 72.7%) groups of plants. In the coenotic structure of the flora of studied forests, the forest (38 species; 31.4%) and ruderal (37 species; 30.6%) fractions were the leading ones, while the third position was occupied by the psammophytic species (22; 18.2%). A high number of weeds in the flora composition is explained by urbanization. Fractional analysis of the flora has shown a predominance of native species (90; 75%), mainly apophytes (47; 39.2%), adapted to growing in disturbed habitats. The adventive fraction includes 30 species (25%), among which kenophytes and xenophytes predominate. Localities of three rare species (Dryopteris carthusiana (Vill.) H.P. Fuch, Jurinea charkoviensis Klok., and Viburnum opulus (L.) Opiz.) were identified, which indicated conservation value of the study area. An index of the flora synanthropization (64.5%) is quite high due to ruderal species adapted to disturbed habitats. The studied valley forests are under anthropic pressure caused by nearby settlements via littering and deforestation, which results in flora impoverishment and the spread of alien plant species. Therefore, the forests in question require further monitoring.

Geographical distribution of the dispersal ability of alien plant species in China and its socio-climatic control factors

Dispersal ability is important for the introduction, establishment, and spread of alien plant species. Therefore, determination of the geographical distribution of the dispersal ability of such species, and the relationship between dispersal ability and socio-climatic factors are essential to elucidate the invasion strategies of the alien plant species. Analytic hierarchy process and inventory, risk rank, and dispersal mode data available on Chinese alien plant species were used to determine their dispersal ability, the geographical distribution thereof, and the relationship between socio-climatic factors and dispersal ability. High-risk alien plant species had a higher natural dispersal ability (or several natural dispersal modes) but a lower anthropogenic dispersal ability (or few anthropogenic dispersal modes) than low-risk alien plant species. The geographical distribution of the dispersal ability of the alien plant species showed an inverse relationship with species density. Alien plant species with low dispersal ability (i.e., with fewer dispersal modes and distribution in the southeast) showed a tendency to adapt to environments with mild climates, while those with high dispersal ability (i.e., with more disposal nodes and distribution in the northwest) showed a tendency to adapt to harsh environments. It is essential for land managers and policy makers to understand the geographical distribution of the dispersal ability of alien plant species and their socio-climatic control factors to formulate strategies to control the natural and anthropogenic dispersal of such plants.

Alien flora across European coastal dunes

AbstractQuestionsThe spread of alien plant species is one of the main threats to the biodiversity of different natural habitats, and coastal dune habitats are among the most affected. There is a considerable local and regional variation in the level of alien plant invasion on coastal dunes. We asked what are the patterns of invasion across European coastal dunes and how they depend on habitat types and coastal regions.LocationAtlantic, Baltic, Black Sea and Mediterranean coasts of Europe.MethodsWe used vegetation‐plot records from shifting dunes and stable dune grasslands extracted from the European Vegetation Archive (EVA). We quantified richness, frequency and distribution of alien plant (neophyte) species across dune habitats and coastal regions. We also explored the donor habitats and invasion trajectories of these species.ResultsIn the flora of European coastal dunes, 7% of species were neophytes, for two‐thirds originating from outside of Europe and mostly naturalised and ruderal. Shifting and stable dunes were similar in neophyte species composition, but there were more individual occurrences of neophytes in shifting dunes. The neophyte flora composition differed considerably between the Atlantic, Baltic, Black Sea and Mediterranean regions. The highest number of neophyte species was observed on the Atlantic dunes, while the highest number of neophyte occurrences was on the Black Sea dunes. Most of the neophytes originated from North America and the Mediterranean‐Turanian region. Erigeron canadensis, Xanthium orientale, Oenothera biennis and Oenothera oakesiana were the most common neophytes.ConclusionsWe provided a comprehensive assessment of alien plant invasions in the coastal dunes across Europe and highlighted that coastal dunes should be in the focus of European invasion management strategies.

Urban Rivers as Dispersal Corridors: Which Factors Are Important for the Spread of Alien Woody Species along the Danube?

Cities are hotspots of invasions, and this is particularly the case for urban rivers, which are known to serve as corridors for the spread of alien plant species to floodplain forests. Here, we present a case study on woody (shrubs, trees) species invasions across a gradient from a metropolis (Vienna) to rural regions along the Danube River in eastern Austria. In total, we identified 44 native and 25 alien woody species in 75 plots. Five alien woody species occur in at least 10 plots. The most wide-spread ones were species of floodplain forests (Acer negundo, Fraxinus pennsylvanica, and Populus x canadensis), while Ailanthus altissima and Robinia pseudoacacia—which prefer dry sites—were recorded substantially less often. The average level of invasion—i.e., the relative proportion of alien to native woody species in plots—was high across all three study regions. Still, there was a moderate decline of alien woody species richness along the urban—peri-urban—rural gradient. Generalized Linear Mixed Models showed that population density and the proportion of urban habitats in the environs of the plots is significantly positively correlated with the presence of Acer negundo and Ailanthus altissima. Conversely, the occurrence of Robinia pseudoacacia is negatively correlated with surrounding population density and urban habitats. Occurrence of Acer negundo is positively correlated with urban habitats. For Fraxinus pennsylvanica, we found no significant relationships. Our results confirm that gallery forests at river banks are highly susceptible to invasions. We argue that managing alien woody species in urban and peri-urban sites is not appropriate and useful, given that re-invasion is likely in most cases (from adjacent urban green spaces). We acknowledge that this recommendation entails the implicit recognition that gallery forests along urban sections of the Danube will contain a substantial—and likely further increasing—proportion of alien woody species.

A preliminary assessment of green areas of Matera city and their potential role in climate change

Urban greening offers a series of services including the improvement of air quality, water cycle, through several functions (e.g., absorption of air pollutants, increasing water catchment operated by soil). There is increasing attention to quantify urban green areas and the related benefits to the extent that the Italian National Statistics Institute (ISTAT) scores the “green value” of the main cities. There are still uncertainties on the classification of the green areas and their potential to provide services that collectively improve the urban life quality. This study analysed the green areas of the urban environment of Matera city, focussing on their category (private gardens, school gardens, green streets and urban parks) and size and their potential to serve as CO(2) sink. The analyses were carried out on four representative areas and the size of the various categories was assessed through cadastral and other municipal data. The urbanization process had influences on urban ecosystems including plant biodiversity, increasing the abundance of plant alien species. Knowledge on the spread of alien plant species might help to prevent the biodiversity loss. Therefore, a qualitative survey of the existing alien plant species in the urban environment was performed. Preliminary results show that the urban green area calculated in this study is 90 ha. In addition, private gardens share a higher surface of urban green areas, reflecting a good greening aptitude of citizens. Considering that the green areas within built environment is most beneficial for human well-being, a possible scenario related to the carbon (C) sequestration by these areas in Matera city will be presented. A potential green corridor connecting some existing spot green areas to promote social aspects and improve well-being of citizens and environmental sustainability will also be discussed. This study might be supportive for urban planners and local policy makers, contributing to drive future decisions towards a greener built environment of Matera city.

Environmental and anthropogenic determinants of the spread of alien plant species: insights from South Africa’s quaternary catchments

Alien plants invasion has negative impacts on the structure and functionality of ecosystems. Understanding the determinants of this process is fundamental for addressing environmental issues, such as the water availability in South Africa’s catchments. Both environmental and anthropogenic factors determine the invasion of alien species; however, their relative importance has to be quantified. The aim of this paper was to estimate the importance of 32 explanatory variables in predicting the distribution of the major invasive alien plant species (IAPS) of South Africa, through the use of Species Distribution Models. We used data from the National Invasive Alien Plants Survey, delineated at a quaternary catchment level, coupled with climatic, land cover, edaphic, and anthropogenic variables. Using two-part generalized linear models, we compared the accuracy of two different sets of variables in predicting the spatial distribution of IAPS; the first included environmental correlates alone, and the second included both environmental and anthropogenic variables. Using Random Forest, we explored the relative importance of the variables in producing a map of potential distribution of IAPS. Results showed that the inclusion of anthropogenic variables did not significantly improve model predictions. The most important variables influencing the distribution of IAPS appeared to be the climatic ones. The modeled potential distribution was analyzed in relation to provinces, biomes, and species’ minimum residence time.

Spread of alien plant species in the habitats of the Ukrainian Forest Steppe

Abstract In order to assess the level of anthropogenic transformation of the vegetation cover of the nature protected areas located within the Ukrainian Forest Steppe, we have analysed the distribution of alien species in natural and anthropogenic habitats. All recorded species are represented in habitats shaped by human activity: dominated by phanerophytes, which included deciduous and coniferous woodlands as well as shrublands of Rhamno-Prunetea class. The same number of species was found in grassland habitats and is caused by the huge number of potential ecological niches as a result of the complex structure and also by the proximity of transportation networks and watercourses. Biotopes of chamaephytes and nanophanerophytes, though being represented in all the studied sites, often have a very narrow ecological amplitude and occupy small areas, making it difficult for alien species to spread. About one-third of species were recorded across at least three habitat types; such species may be considered eurytopic in their secondary ranges. Most widespread species were Fallopia convolvulus L., Vicia angustifolia Reichard, Ambrosia artemisiifolia L., Conyza canadensis (L.) Cronqist, Phalacroloma annuum (L.) Dumort. and Setaria viridis (L.) P. Beauv. At the same time, there was not a single species that would have occurred in all habitat types. In sum, agricultural lands and ruderal biotopes were highly invaded; three times less alien plant species occurred in woodlands, shrublands, grasslands and wasteland; and only small number of non-native species were restricted to continental water habitats.

Effects of road type and urbanization on the diversity and abundance of alien species in roadside verges in Western Siberia

The spread of alien plant species by vehicles profoundly affects the roadside vegetation. Roads with high traffic densities in urban regions may facilitate the invasion of alien plants. The present study examined the effects of road type and distance to the city centre on native and alien plant species in both the aboveground vegetation and soil seed bank of road verges in originally dry steppe grasslands in the surroundings of Pavlodar, Western Siberia, Kazakhstan. This region is characterized by a recent change of land use and rapidly expanding urbanization. Vegetation surveys were conducted at 12 sites distributed along roads with different traffic densities (national and local roads) and at two distances to the city centre (city edge and rural surroundings). The seedling-emergence method was used to examine the soil seed bank at each site. We found a larger percentage of alien species along national roads (42 % in the aboveground vegetation, 57 % in the soil seed bank) than along local roads (20 and 44 %, respectively), which can be explained by differences in traffic density, location from which the vehicles come and habitat conditions. More alien species were found in the road verges at the city edge than in the rural surroundings along both road types, probably due to the spread of propagules from residential areas. Our study demonstrates that national roads are important pathways for the introduction of alien species in this Western Siberian region.

The occurrence of alien species in the settlement areas of the Kampinos National Park and its vicinity (Central Poland)

Abstract Studies aimed at the identification of the range and method of spread of alien plant species in settlement areas in Kampinos National Park (KNP) and its immediate vicinity were carried out in years 2012-2014. Special emphasis was put on surveying the sites of invasive alien species (IAS), and diagnosing potential threats posed to the natural and semi-natural vegetation of the national park by the IAS present in rural areas. We found 53 alien vascular plant species, including 40 invasive taxa which may potentially pose a threat to the ecosystems of KNP. Species encroaching from settlement areas to semi-natural and natural communities included: Bidens frondosa, Echinocystis lobata, Impatiens glandulifera, I. parviflora, Juncus tenuis, Lupinus polyphyllus, Reunoutria japonica and Solidago gigantea. Most of them were species from the highest invasiveness (IV and III) classes in Poland. Similarity analysis carried out for all investigated localities with regard to all alien species, and only for invasive ones showed a clear division into separate groups: villages within the boundaries of the national park and villages outside the park.

Ecology: Global trends in plant naturalization.

Many naturalized non-native plants pose ecological and economic threats. A quantitative analysis of the global distribution of naturalized plants confirms some anticipated trends and exposes new patterns. See Letter p.100 Human activity has facilitated the spread of alien plant species around the globe, many of which have become naturalized on different continents. Mark van Kleunen et al. construct a global database of alien plant introductions, showing that more than 13,000 species — nearly 4% of the total flora — have become naturalized in a new location. North America has received the most alien plants, while the Pacific islands are accumulating them at the fastest pace, and the Northern Hemisphere is the predominant donor of alien species.

The Effects of Habitat Type and Volcanic Eruptions on the Breeding Demography of Icelandic Whimbrels Numenius phaeopus.

Distinct preference of species for habitats is most often driven by long term differences in demographic rates between habitats. Estimating variation in those rates is key for developing successful conservation strategies. Stochastic events can interact with underlying variation in habitat quality in regulating demography but the opportunities to explore such interactions are rare. Whimbrels in Iceland show a strong preference for sparsely vegetated riverplains. Such habitats in Iceland face various threats, e.g., climate change, river regulation and spread of alien plant species. In this study we compared demographic parameters of breeding Whimbrels between riverplains and other habitats before, during and after volcanic eruption events to estimate the importance of the habitats for the species and the effect of ash deposit on breeding success. We found that an estimated minimum of 23% of the Icelandic population of Whimbrels and c. 10% of the world population of the species breed in riverplain habitats in Iceland. Whimbrels bred consistently at much higher densities in riverplain habitats than in other habitats and riverplains also had higher densities of pairs with fledglings although the proportion of successful breeders was similar between habitats. Predation by livestock may have had a considerable negative effect on breeding success on our study sites. Breeding was negatively affected by the volcanic activity, probably through the effects of ash on the invertebrate food supply, with breeding success being gradually worse closer to the eruption. Breeding success was equally affected by volcanism across habitats which differed in underlying habitat quality. This study gives an example of how populations can be regulated by factors which operate at different spatial scales, such as local variation in habitat quality and stochastic events which impact larger areas.

Exploring changes in the invasion pattern of alien flora in Catalonia (NE of Spain) from large datasets

Plant invasions are characterized by their dynamism, but they are generally described at a precise time step due to the dearth of datasets on species distribution across time. In this paper we employed specific alien plant databases to assess the factors associated with recent changes in plant invasion patterns in Catalonia from two perspectives, site and species. We gathered records of neophyte plant species per 10-km UTM cell from two spatially coincident large-scale datasets collected in 1989 and 2012. We estimated the richness increase of species per UTM cell and the range size increase of each species (i.e. the number of occupied UTM cells) between these dates. We then evaluated the association of richness increase with geographic, climatic and landscape factors, and that of range size increase with species traits and the characteristics of the introduction event. We found 401 species, 291 recorded up to 1989 and 110 afterwards. Richness increase was concentrated in new hotspots compared to those observed in 1989, suggesting that patterns of susceptibility to plant invasion have changed in recent decades. Climatic factors were the most important in determining the large-scale pattern of alien species, with the highest values of species richness increase in warmest and rainiest areas. Range size increase of each alien species was mostly explained by the historical range size, the introduction pathway, namely unintentional introductions and the interaction between habitat and the minimum residence time. These factors were more influential than species traits in the recent spread of alien plant species across the region.

Post-fire spread of alien plant species in a mixed broad-leaved forest of the Insubric region

How do tree species regenerate and which ecological conditions are required after forest fire in the Insubric region of the Alps? Are indigenous stand-forming tree species resistant over the invasion of alien plant species after such a disturbance? We addressed these questions in a case study in the Swiss canton of Ticino. In April 2006, a surface fire with severe intensity burnt a forest area of 55 ha on a south-facing slope (400–800 m.a.s.l.). The dominant trees in the investigated area were chestnut ( Castanea sativa Mill.), beech ( Fagus sylvatica L.) and deciduous oaks ( Quercus spp.) mixed with tree species of intermediate height. Vegetation data were collected in May and August 2009 by systematic sampling. Resprouting of the survived trees and generative regeneration were analysed by counting vegetative shoots from sprouting stools, of seedling age, height and damage rate, respectively. Different vegetation structures related to low or high fire intensity were clearly visible three years after the forest fire, creating various habitats for both new invaders and seedlings of the stand-forming trees. The dominant chestnut was the only tree species that regenerated effectively by sprouting from stools. Seedlings of the stand-forming trees grew in high abundance under shadow conditions close to their mother trees which provided the seed source. In contrast, pioneer trees invaded patches where full light was available. Under such conditions the two main woody alien plant species, Ailanthus altissima and Robinia pseudoacacia, grew in high abundance. Due to the different ecological requirements of indigenous and alien tree seedlings, not any interaction between the two groups was detected.

Establishment of parallel altitudinal clines in traits of native and introduced forbs

Due to altered ecological and evolutionary contexts, we might expect the responses of alien plants to environmental gradients, as revealed through patterns of trait variation, to differ from those of the same species in their native range. In particular, the spread of alien plant species along such gradients might be limited by their ability to establish clinal patterns of trait variation. We investigated trends in growth and reproductive traits in natural populations of eight invasive Asteraceae forbs along altitudinal gradients in their native and introduced ranges (Valais, Switzerland, and Wallowa Mountains, Oregon, USA). Plants showed similar responses to altitude in both ranges, being generally smaller and having fewer inflorescences but larger seeds at higher altitudes. However, these trends were modified by region-specific effects that were independent of species status (native or introduced), suggesting that any differential performance of alien species in the introduced range cannot be interpreted without a fully reciprocal approach to test the basis of these differences. Furthermore, we found differences in patterns of resource allocation to capitula among species in the native and the introduced areas. These suggest that the mechanisms underlying trait variation, for example, increasing seed size with altitude, might differ between ranges. The rapid establishment of clinal patterns of trait variation in the new range indicates that the need to respond to altitudinal gradients, possibly by local adaptation, has not limited the ability of these species to invade mountain regions. Studies are now needed to test the underlying mechanisms of altitudinal clines in traits of alien species.

Do urban areas act as foci for the spread of alien plant species? An assessment of temporal trends in the UK

ABSTRACTAim Given that urban landscapes often act as a point of entry for many non‐native species and urban development continues to increase as the human population rapidly expands, an understanding of the interaction between urbanization and non‐native plant species is important both in the control of potentially invasive species and in the conservation of native biodiversity. We investigated the spatial and temporal relationship between urban land cover and the distribution of non‐native species in Britain using two floristic data sets collected at two different time periods: 1987–88 and 2003–04.Location UK.Methods Using floristic data collected by the Botanical Society of the British Isles in 1987–88 (Monitoring Scheme) and 2003–04 (Local Change) in conjunction with habitat data obtained from the Land Cover Map of the UK, we conducted multiple regression analyses both within and between years on both groups of species (natives, neophytes and archaeophytes) and individual species.Results Neophytes (alien species introduced after 1500) were very strongly associated with urban land cover in both time periods and do not appear to be spreading out of urban habitats into the wider countryside. Archaeophytes (alien species introduced before 1500), however, showed a strong association with urban habitats in the earlier 1988 data set but no longer showed this association in the 2004 data set. Analysis at the individual species level showed that a large percentage of alien plant species, particularly archaeophytes, were not strongly associated with urban land cover or were negatively associated with such habitats.Main conclusions Our results suggest that there has been a reduction in the urban association of archaeophytes that is likely to have resulted from the recovery of archaeophytes associated with non‐urban (especially arable) habitats, following their decline in mid‐20th century, rather than from the movement of aliens into the wider countryside from urban habitats.

Fruit type, life form and origin determine the success of woody plant invaders in an urban landscape

The spread of alien plant species is a critical ecological event worldwide, but the forces that control this spread are not well documented. Alien plant species are well known to disrupt ecological services of native ecosystems, change the composition of native habitats, and often lead to the extirpation of native flora and fauna. Here, we report on life history patterns of plant species with rapidly spreading and declining ranges in North America’s major urban region. We tested for differences in life history traits between the 466 native and alien woody flora of the New York metropolitan area. We also examined the relationship between life history traits and change in distribution in the New York metropolitan area between 1900 and 2000. Native and alien species of the New York metropolitan area differ with respect to pollination vector and breeding system. However, pollination vector and breeding system are not associated with success, defined here as increasing range spread in the urban environment; instead, fruit type (dispersal), life form and origin are important determinants of success. Alien species that are deciduous trees, shrubs or vines with fleshy fruit are the most successful in increasing their distribution in this urban landscape. Newly introduced species with these characteristics are expected to have a better chance at establishing in similar urban landscapes and should be targets for intensive management. The ability to predict which alien species will become invasive is also a valuable tool for the prevention of invasions by newly introduced plant species.

Phenology is a major determinant of tree species range

Global warming is expected to have a major impact on plant distributions, an issue of key importance in biological conservation. However, very few models are able to predict species distribution accurately, although we know species respond individually to climate change. Here we show, using a process‐based model (PHENOFIT), that tree species distributions can be predicted precisely if the biological processes of survival and reproductive success only are incorporated as a function of phenology. These predictions showed great predictive power when tested against present distributions of two North American species – quaking aspen and sugar maple – indicating that on a broad scale, the fundamental niche of trees coincides with their realized niche. Phenology is shown here to be a major determinant of plant species range and should therefore be used to assess the consequences of global warming on plant distributions, and the spread of alien plant species.