When you're about to sit on the toilet and you fart right before sitting down so that the fart cloud is at nose level, effectively giving yourself a cropdust.
I just went to take a massive dump and accidentally gave myself a Cropdust Kamikaze. It was like sitting in a poisonous cloud.
farting in a crouded hallway after eating food from a mexican restaraunt like chipotle or taco bell.
dude,. do you smell that?!
ya, i think steve had mexican food last night i think he's a mexican cropduster today