Written by: Christina Myrdal
Determining whether a species is considered native or introduced is not as straightforward as you might think.
The question of whether a plant is native or introduced may differ depending on the source you are using and which geographical area you are referring to. For example, a plant can be native to Canada, but not native to certain provinces (e.g. Manitoba Maple). You may have noticed that some sources even differ in their display of native species ranges.
The term native is defined as “of indigenous origin or growth”. Native species are therefore defined as those which originate from a given area prior to human intervention. These species have evolved over thousands of generations as part of a cohesive ecosystem alongside other native wildlife and have adapted to the environmental conditions present in a given region.
Non-native or introduced species are those which were introduced by human intervention, the timing of which is often attributed to European settlement when plants and animals could more easily be relocated to new parts of the world where they don’t naturally occur. You may have noticed that many of the highly prevalent invasive species in North America are of Eurasian origin, such as Japanese Knotweed, European Common Reed, and Common Buckthorn. While many species are easy to classify as native or non-native, this is not always the case.
Many species’ origins are difficult to trace and it may be unclear whether they are truly ‘native’ or were introduced so long ago and successfully naturalized. In these cases, it is helpful to review provincial or federal species rankings for the most current assessment of a given species based on available science.
Network of Nature’s native/non-native species locality filter is consistent with the distributions listed in the Database of Vascular Plants of Canada (VASCAN). VASCAN uses data from a variety of sources and references to include widely-accepted native statuses for species in the geographical ranges that they cover.
If you want to learn more about native species, be sure to check out our Blog Post here!
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