In music, "ground" is a term that refers to an underlying bass pattern over which a melody is laid. (This is also known as a "pedal point.") Minneapolis resident Brad Peterson has added a new layer of meaning to that term, composing a "Lawn Mower Opus in G" over the drone of a...yep, you got it.
In an video about the making of the piece, Peterson explains that the composition's seed was planted (if you will) when he was ten years old: as he mowed his family's lawn, he improvised a melody in the key of the mower's roar. Years later, after he'd learned music composition and performance, hearing a neighbor's mower reminded Peterson of his childhood inspiration.
"Basically, every instrument I had at some point tried to make a part, and built it and built it and built it into this orchestral work and just tried to recreate this magical...the evolution of a song with the naïvete of a ten-year-old boy humming along with his lawnmower."
Here's the song, with a video also created by Peterson.