Scientists have developed an environment-friendly robot that can spot weeds in the middle of a crop.

It uses face recognition software to tell which is which.

Tests on sugar beet fields in Denmark have shown that selectively spraying weeds mapped by the robot can reduce herbicide use by 70%.

A later version of the robot will be able to kill weeds as well as apply a few drops of herbicide.

But the ultimate goal is to build a machine that plucks weeds out of the ground rather than poisons them.

More here.