Hedge Bindweed is a rampant climber, which can completely cover hedge and fences. It has an extensive branched root system, and can be difficult to eradicate as a garden weed because even small fragments of the roots can grow into new plants. The white trumpet-shaped flowers appear in summer.
A similar introduced species is Greater or Large Bindweed (Calystegia sylvatica), which is more vigorous and has larger flowers.