Adventive plants or adventitious plants are plants that have established themselves in a place that does not correspond to their area of origin due to anthropogenic influence and, therefore, are all wild species that have only been established with the help of humans, in contrast to the native species.
The term "adventive" is used to describe species that are not self-sufficient, but need an episodic population assistance from their homeland. If, however, an adventive species becomes self-sustaining in its new geographic area, it is then naturalized. [1]
The term hemerochory is sometimes used synonymously with this one, but is often restricted to species that were unintentionally brought into the area and then naturalized, sometimes also for species that have firmly established themselves in their new habitat.
Depending on the question and perspective, adventitious plants are divided into different subcategories:
The year 1492 is a conventionally chosen reference point. With the "discovery" of America and the Age of Discovery and colonialism, alien species from other parts of the world came to new areas on a large scale. Most of the archaeophytes immigrated with the introduction of agriculture (in the Neolithic). The status of a species as an archaeophyte is usually deduced (from the location and ecology of the species) and is hardly directly detectable.
Spontaneous immigrants (sometimes referred to as "acolutophytes") immigrated on their own without direct human assistance, for example when new locations were created through culture or soil changes. Companions (sometimes also "xenophytes") were brought in through human transport. Examples would be seed companions, which were unintentionally sown due to their similarity to cultivated plant seeds, or “wool adventures”, which were dragged into the wool fleece during the transport of sheep's wool.
Feral species or cultural refugees in the narrower sense are those that were originally cultivated, but later escaped from the culture and were able to spread on their own. Such descendants of original cultural clans are subject to natural evolution as they become wild and can more or less quickly differ both from the culture form itself and from the original wild clan that preceded the culture.
Adventitious plants are often found at freight stations, along railway lines and port areas as well as airports, but also on roads. Seeds of many species were accidentally imported there with the import of goods (so-called agochoria). Occasionally, seed contamination also introduces new plants that could reproduce for a short period of time (so-called speirochory). Agochory and speirochory are sub-forms of hemerochory. The seeds can also hang in wheel arches so that they can be transported and distributed along highways.
The proportion of adventitious species in open ruderal corridors at such locations can exceed 30% of the flora of these locations. In natural and near-natural vegetation, adventitious plants are much rarer. Their share here is between zero and about 5%. [6]
Avena is a genus of Eurasian and African plants in the grass family. Collectively known as the oats, they include some species which have been cultivated for thousands of years as a food source for humans and livestock. They are widespread throughout Europe, Asia and northwest Africa. Several species have become naturalized in many parts of the world, and are regarded as invasive weeds where they compete with crop production. All oats have edible seeds, though they are small and hard to harvest in most species.
A feral animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some cases, contributed to extinction of indigenous species. The removal of feral species is a major focus of island restoration.
Pioneer species are resilient species that are the first to colonize barren environments, or to repopulate previously biodiverse steady-state ecosystems that have been disrupted by natural disasters such wildfire, flood, mudslide, lava flow or a climate-related extinction event or by anthropogenic habitat destruction.
An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are new biota to their environment in terms of established biological network relationships. Neobiota can further be divided into neozoa and neophyta (plants).
In spermatophyte plants, seed dispersal is the movement, spread or transport of seeds away from the parent plant. Plants have limited mobility and rely upon a variety of dispersal vectors to transport their seeds, including both abiotic vectors, such as the wind, and living (biotic) vectors such as birds. Seeds can be dispersed away from the parent plant individually or collectively, as well as dispersed in both space and time. The patterns of seed dispersal are determined in large part by the dispersal mechanism and this has important implications for the demographic and genetic structure of plant populations, as well as migration patterns and species interactions. There are five main modes of seed dispersal: gravity, wind, ballistic, water, and by animals. Some plants are serotinous and only disperse their seeds in response to an environmental stimulus. These modes are typically inferred based on adaptations, such as wings or fleshy fruit. However, this simplified view may ignore complexity in dispersal. Plants can disperse via modes without possessing the typical associated adaptations and plant traits may be multifunctional.
A synanthrope is an organism that lives near and benefits from humans and their environmental modifications. The term synanthrope includes many species regarded as pests or weeds, but does not include domesticated animals. Common synanthrope habitats include houses, gardens, farms, parks, roadsides and rubbish dumps.
Capsella bursa-pastoris, known as shepherd's purse because of its triangular flat fruits, which are purse-like, is a small annual and ruderal flowering plant in the mustard family (Brassicaceae). It is native to eastern Europe and Asia minor, but is naturalized and considered a common weed in many parts of the world, especially in colder climates, including British Isles, where it is regarded as an archaeophyte, North America and China, but also in the Mediterranean and North Africa. C. bursa-pastoris is the second-most prolific wild plant in the world, and is common on cultivated ground and waysides and meadows.
Naturalisation is the ecological phenomenon through which a species, taxon, or population of exotic origin integrates into a given ecosystem, becoming capable of reproducing and growing in it, and proceeds to disseminate spontaneously. In some instances, the presence of a species in a given ecosystem is so ancient that it cannot be presupposed whether it is native or introduced.
A tumbleweed is a structural part of the above-ground anatomy of a number of species of plants. It is a diaspore that, once mature and dry, detaches from its root or stem and rolls due to the force of the wind. In most such species, the tumbleweed is in effect the entire plant apart from the root system, but in other plants, a hollow fruit or inflorescence might detach instead. Xerophyte tumbleweed species occur most commonly in steppe and arid ecosystems, where frequent wind and the open environment permit rolling without prohibitive obstruction.
The need for a clearly defined and consistent invasion biology terminology has been acknowledged by many sources. Invasive species, or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats. Invasion biology is the study of these organisms and the processes of species invasion.
Linaria vulgaris, the common toadflax, yellow toadflax or butter-and-eggs, is a species of flowering plant in the family Plantaginaceae, native to Europe, Siberia and Central Asia. It has also been introduced and is now common in North America.
Lathyrus aphaca, known as the yellow pea or yellow vetchling, is an annual species in the family Fabaceae with yellow flowers and solitary, pea-like fruits. It originated in the Middle East and has spread throughout Europe and beyond as a weed of cultivated fields and roadsides. The fruits are eaten as a supplement to diets in some parts of South Asia but are narcotic and potentially toxic in large quantities.
An archaeophyte is a plant species which is non-native to a geographical region, but which was an introduced species in "ancient" times, rather than being a modern introduction. Those arriving after are called neophytes.
A weed is a plant considered undesirable in a particular situation, growing where it conflicts with human preferences, needs, or goals. Plants with characteristics that make them hazardous, aesthetically unappealing, difficult to control in managed environments, or otherwise unwanted in farm land, orchards, gardens, lawns, parks, recreational spaces, residential and industrial areas, may all be considered weeds. The concept of weeds is particularly significant in agriculture, where the presence of weeds in fields used to grow crops may cause major losses in yields. Invasive species, plants introduced to an environment where their presence negatively impacts the overall functioning and biodiversity of the ecosystem, may also sometimes be considered weeds.
Strophostyles is monophyletic three-species genus of flowering plants in the family Fabaceae, subfamily Faboideae. Common names for the genus include wild bean and fuzzybean. It consists of annual and perennial herbaceous vines, ranging in their native distribution from Nevada, east to Florida, and north to the Great Lakes and eastern Canada. The etymology of the name is strophe (turning) + stylos (style), referring to the curve of the style within the keel petal.
Oenanthe pimpinelloides is a species of flowering plant in the family Apiaceae known by the common name corky-fruited water-dropwort. It is a plant of damp or dry grassland and more ruderal tall herb communities.
In botany, a neophyte is a plant species which is not native to a geographical region and was introduced in recent history. Non-native plants that are long-established in an area are called archaeophytes. In Britain, neophytes are defined more specifically as plant species that were introduced after 1492, when Christopher Columbus arrived in the New World and the Columbian Exchange began.
An escaped plant is a cultivated plant that has escaped from agriculture, forestry or garden cultivation and has become naturalized in the wild. Usually not native to an area, escaped plants may become invasive. Therefore, escaped plants are the subject of research in invasion biology.
Hemerochory, or anthropochory, is the distribution of cultivated plants or their seeds and cuttings, consciously or unconsciously, by humans into an area that they could not colonize through their natural mechanisms of spread, but are able to maintain themselves without specific human help in their new habitat.