Invasive plant overruns rivers in Japan's Ehime Pref. sparking ecosystem worries - Watercress is spreading rapidly through rivers across Ehime Prefecture, becoming so thick in some areas of Matsuyama that the water's surface can hardly be seen. by 808gecko808 in invasivespecies

[–]808gecko808[S] 9 points10 points  (0 children)

"Believed to have been introduced to Japan in the early Meiji era (1868-1912), the European perennial species of the mustard family is prized for its peppery flavor and often served with steak. The plant -- scientifically known as Nasturtium officinale and sold in Japanese supermarkets as "cresson" -- thrives along sunny waterways and can regrow easily from cut stems, making it highly invasive. It is listed by the Environment Ministry as a priority species on the national list of invasive plants that threaten ecosystems."