THE rim of Lake Tempe glitters like a mirror during the day, reflecting the bright afternoon sun. Located in the village of Laelo in South Sulawesisome three hours drive from provincial capital Makassartourists flock to the lake to enjoy idyllic picnics.

Just five kilometers away, however, the glistening water disappears into a dense cluster of water hyacinth (Eichhornia crassipes).

"It is much better now. Three years ago, the plant had crept up a