Rising temperatures are boon to exotic invaders

Plants from semi-tropical climes are overtaking native British species and choking habitat as they flourish in warmer conditionsA half-degree increase in the average temperature in September and October in East Anglia this century has made an already troublesome plant invader even more of a nuisance. While the change in climate has been hardly noticeable to humans, it has made an enormous difference to the floating pennywort, Hydrocotyle ranunculoide, which already threatens to choke slow-moving