As long as they aren't display objects on the chain and there aren't any other ref's, collection should kick in almost immediately when they're spliced from the vector. If there's any question, refer to this thread:

http://board.flashkit.com/board/show...t=active+graph

I posted the code for a good class called ActiveGraph there (not written by me) that's useful for testing whether you're getting collection. Read the thread for details about how to use it...