Concept
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. 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: Archaeophytes were introduced before 1492 Neophytes were introduced or immigrated after 1492. 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. Agriophytes: species that have invaded natural or near-natural vegetation and could survive there without human intervention. Epecophytes: Species that are only naturalized in vegetation units shaped by humans, such as meadows, weed flora or ruderal vegetation, but are firmly naturalized here. Ephemerophytes: Species that are only introduced inconsistently, that will die out of culture for a short period of time, or that would disappear again without a constant replenishment of seeds.
