Alien willow rings alarm bells in the Northeast
Ludwigia peruviana is spreading rapidly in Assam, posing a threat to the state's biodiversity. The weed, called primrose willow, is native to Central and South America, and flourishes in sandy and mineralrich soil of wetlands. Researchers with the Assam Agricultural University and Tinsukia-based action group, Evergreen Earth, say the weed has already damaged marshland plants, particularly along the Dhansiri and Kopili rivers, and has been competing with plants in peat-land ecosystem since it was spotted in Karbi Anglong district in 1993. The invasive weed can clog natural waterways, increase sedimentation, result in accumulation of organic matter causing deoxygenation of water columns, which in turn, can lead to disruption of fresh aquatic organisms. The researchers have called for urgent management of the weed, which has also been spreading in Tamil Nadu, Kerala, the Andamans and West Bengal.