Alien plant species
1 in 10 plants is an alien
In the Flemish Region the percentage of alien plant species has doubled since the 1970s: from about 5% in 1972 to around 10% in 2019. This percentage refers to the proportion of alien plant species per km² within the total number of species per km².
The increase in international transport has resulted in a permanent supply of new alien plant species. Some of those alien plant species manage to naturalize and to disperse spontaneously. The dispersion of plants from horticulture (e.g. by dumping garden waste) is one of the most important channels through which alien plants are introduced.
Some alien plant species become invasive after some time, as they spread very rapidly and exhibit explosive growth. They may thus disrupt indigenous biodiversity.