Go to the far right of the main town and throw the boomerang to the right. Quickly dash left all the way to the other side of town and once you get to the trees, the boomerang will keep looping around the screen repeatedly. Once it's looping, it will destroy bushes, as well as put the image of a destroyed bush all over where it isn't supposed to be (like on the pathway, etc.).
Submitted by: Deathknight