G1 - Open sand steppes:
It is one of the most endangered habitats, 69% of its area is threatened by plant invasion. The most important invaders are common milkweed (Asclepias syriaca) and black locust (Robinia pseudoacacia). The area threatened by invasion of tree of heaven (Ailanthus altissima) and Russian olive (Elaeagnus altissima) is smaller, but not negligible.
