Working towards a helicopter

Bob desperately wants a remote control helicopter. To raise funds, he is weeding the front yard for me. I love his enthusiasm. He goes after each one with a jump and a thrust and a grunt to make sure he kills it dead (ie gets the whole root). He will get higher pay for picking up dog poop in the back yard. But since it rained quite heavily yesterday, I thought the weeding task was more humane and sanitary.