Alien plants 'threaten the environment'

Alien plants invading Britain from garden centres pose more of a threat to the environment than any so-called superweeds resulting from genetically modified (GM) crops, a leading scientist has warned.

Alien plants invading Britain from garden centres pose more of a threat to the environment than any so-called superweeds resulting from genetically modified (GM) crops, a leading scientist has warned.

Lord May of Oxford, president of the Royal Society and a former chief scientific adviser to the Government, says the threat of GM crops cross-breeding with weeds has been greatly exaggerated by what he called fundamentalist lobby groups. Some environmental groups have suggested that pollen from GM crops could accidentally fertilise related species growing in the wild to produce weeds resistant to herbicides.

In his annual presidential address released yesterday and to be delivered today, Lord May says the real threat comes from pernicious and invasive foreign plants that have been deliberately introduced as ornaments for British gardens. "Pollen from 'conventional' crops – many of which have been produced by very hi-tech methods in recent years, which would easily be seen as Frankensteinian if you so choose – blows around, and does create hybrids.'' he conceded. "But, far from being superweeds, these are typically wimps.

"There are, however, real problems with invasive species in the UK, but they come from plants you can buy at garden centres," he said. "Among several current examples are the invasive aquatic weeds Australian swamp stonecrop, Crassula helmsii, which first 'escaped' garden ponds in 1956 and now infests over 2,000 sites nationwide. [Another weed is] the floating pennywort, Hydrocotyle ranunculoides, now a major problem in the Exminster Marshes and Pevensey Levels."

Lord May said some environmental lobby groups were raising important questions on the safety of GM crops but others took a more fundamentalist point of view. "They know by dogma, instinct or political ideology that GM crops are bad, and the scientific facts are irrelevant. None of these groups seem particularly concerned about the known invasive species sold at garden centres."

Lord May said there was a genuine worry that GM crops would lead to agriculture becoming even more intensified, leading to crops eaten solely by humans. "The consequence is fewer wild plants, fewer insects, fewer birds and an ever more silent spring," he said.