Converting Weeds to Wealth

Is illegal immigration only of the human variety? The question popped up as I read of a threat to Assam's riverine grassland in the Dibru-Saikhowa National Park.

- MADHAVAN NARAYANAN

Is illegal immigration only of the human variety? The question popped up as I read of a threat to Assam's riverine grassland in the Dibru-Saikhowa National Park. The state now faces an influx of plant species that are hurting local ecologies, like unwanted human intruders being blamed for the ills of local economies.

As if the Brahmaputra floods and increasing human encroachment were not enough, the sensitive habitat that is home to feral horses is under threat from invasive species, according to a recent article in the Earth journal. The threats include the weed Parthenium hysterophorous and Mikania micrantha, a fast-creeping vine. On a single day this month, Assam's forest officials cleared more than 5 acres of harmful weeds, including 'Congress grass' (an intriguing moniker for Parthenium hysterophorous) in Morigaon district.

The names sound creepy enough. But my purpose here is to show it is time for botanists, environmentalists and agriculturalists—not to speak of policymakers, economists and administrators—to think anew on how to turn environmental threats into social or economic opportunities. Down south in Kerala, water hyacinth (Eichhornia crassipes) is common across India and is a green pest of sorts. But it's ubiquitous in the waters of God's own country. To the lay observer, the plant's green carpets across ponds and canals may look beautiful; but in an environmental sense, they are not.