This just applies the herbicide to anything that's green and not dirt. That's not nothing, but still the last tech improvement is using Blue LED's because they

This just applies the herbicide to anything that's green and not dirt. That's not nothing, but still the last tech improvement is using Blue LED's because they see green better. Also cool. It's different to attacking only the weeds, which this technology can't do yet because it's still science fiction for a few more years yet as the headline points out. But it will be cool when it can.