Brought to the Arctic town of Tromsoe as a garden bush decades ago, the "palm" has gone wild and thrived in the harsh environment, taking advantage of the short but intense summer vegetation period when the sun never dips below the horizon. Global warming has made conditions easier for the "palm", which grows up to 2 metres (6 foot) high and whose broad, umbrella-like leaves block out the sun for other vegetation.
It grows by river banks and near snow run-offs, where its devastating effect on local plants make the ground more susceptible to erosion, said Janne Sollie, Director General at Norway's Directorate for Nature Management.
"We believe the Tromsoe palm is now spreading faster than ever," Sollie told Reuters at a climate change conference in Tromsoe, which hosts this year's UN world environment day on Tuesday.
"It was not meant to be in Norway but has become a major concern," she said, adding that her agency was drafting a "national action plan" to contain the plant.
When handled without gloves or protective clothing the palm can shed poisonous particles that cause rashes.
It sheds countless seeds when uprooted, making pesticides a must, Sollie said. "If we don't do anything to protect the spread it could cover large parts of Norway," she said.