I've got a video layer of fire inside an image of a dumpster. I've shrunk the fire down pretty good, but it has bottom edges that go beyond the sides of the dumpster. I don't want to shrink the fire down any more because it looks good at the current size. I did a search in the effect pallette but only found Crop Edges under Animation.
Is there no Crop tool, or is it better to Mask out the edges?
Yes, simply use a mask. AE works non-destructively, so what sense would a crop tool even make?