Grapes, berries and robots: is Silicon Valley coming for farm workers jobs?

The robots have arrived in California's fields. This summer, a self-driving tractor was spotted working rows of vines in Napa valley. Described as resembling a "souped-up golf cart", the tractor runs on an electric battery and can be operated remotely with an app. Farther south, strawberry harvesting robots have been picking fruit. Complete with wheels, clipper-tipped arms and a catchment tray, its maker claims the machine can pick almost as many berries as a human with 95% accuracy.