Few-flowered leek (Allium paradoxum)
This small bulb is a popular garden plant but in the wild it's most common in deciduous woodlands and along hedgerows and river banks.
What's the problem?
It forms very dense carpets of leaves in spring, smothering and out competing native species, particularly early-flowering plants like primrose and moschatel which live in similar habitat types. The flower heads produce many tiny bulbils (tiny secondary bulbs that forms in the angle between a leaf and stem or in place of flowers) which help it to spread, particularly where grazing animals such as deer carry them to new areas on their feet. It can be very invasive in disturbed habitats, and is increasingly abundant throughout its range, especially in southern Scotland.
This species is listed on Schedule 9 of the Wildlife and Countryside Act in England and Wales therefore, it is also an offence to plant or otherwise cause to grow these species in the wild.(link)