The riff: Joked by Crow as a tractor is shown with a plowing implement, breaking up the fields. Joel and the other robots groan at this apparently poor joke.
The explanation: They’re groaning because it’s a pun. A harrow, as it turns out, is the tilling implement consisting of many small rotating blades, pulled behind a tractor. It is typically used after larger plows are used to break up dry ground. The smaller harrow blades can then break up larger clumps and smooth the surface out so it is ready for seeding.
Novelty factor: I grew up in the suburbs, okay? The only time we experienced anything harrowing was when power outages interrupted our videogame playing.
NOW ENJOY THIS HOT HARROWING ACTION!