Headline: Land-Mine-Detecting Plants
This January, the Danish company Aresa Biodetection announced that it had produced an unusual new variant of thale-cress, a small flowering weed: a strain that turns red in the presence of land mines. Aresa scientists had genetically modified the weed so that it reacts to nitrogen dioxide, a gas commonly emitted by explosives. A result is a new way to detect mines: sprinkle the seeds over a suspect area, wait a few weeks for the thale-cress to grow and -- presto -- wherever they turn red, you have danger. ''It's much more efficient,'' says Simon Ostergaard, Aresa's C.E.O. ''It's very tedious to clear mines the normal way. You're putting a stick in the ground every three centimeters. One man can sometimes only do two square meters a day.''