in the muck

The Scientist | Duckweed first appeared in satellite images of Venezuela in 2004 as a mysterious swirl of green on the surface of Lake Marcaibo, doubling in size with each passing day. Marcaibo is one of South America’s largest bodies of water, but with brackish water and few nutrients, it had never harbored this rapid-growing aquatic plant. Local scientists speculated that heavy rains washed sewage and nutrients into the lake along with duckweed colonies from neighboring ponds. By June, they estimated that the world’s smallest flowering plant covered 18 percent of the lake’s surface before it began receding.

The invasion could have been an ecological disaster, but for Rutgers geneticist Randall Kerstetter, it was a sign of hope. In the taxonomic showdown over the ideal organism for producing biofuel, Kerstetter is putting his mental energy into duckweed. “Duckweed is the fastest growing plant,” he says. “If you’re interested in biofuels, you’re interested in biomass.”