Meet the planet-friendly "weed killers"

Xavier is a farmer. He grows grapes to make wine. Like all farmers, he wages a constant war against weeds - plants that steal food and water from his grapes as they grow.

Most farmers use chemicals that kill weeds. Xavier didn't want to use chemicals because he saw that, over the years, the poison the ground and the streams. But Xavier found that if he used a tractor to chop down weeds, the tractor tended to bash into his grapes too. And going around gently pulling out weeds by hand is very hard work - and costs a lot of money to pay people to do it.

Xavier turned to his friend Arnaud, an engineer, to help. You can see Arnaud's solution to Xavier's weed problem in this week's WoW! News app .

If we told you that Arnaud rents out a flock of robot sheep to gently munch down the weeds, would you believe us? Well, you better check out the app!

It's a solution that is kind to the planet. It leaves the weeds growing, which enriches the soil and encourages worms, which are also good for the grapes. But the robot sheep work all day and all night, grazing away, to make sure the weeds don't get above themselves and pinch too much food from Xavier's grapes.

Bravo!