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% to around 10%. This refers to the proportion of alien plant species per km², as compared to 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 them 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 species become invasive after some time and may disrupt indigenous biodiversity.