[pen/Rosie] My family has always used the verb "to foof" (or possibly "fouffe" - the spelling has never been established) for what you do to get ant powder out of the bottle. In fact, the verb often gets repeated to become "I'm just going to foofoofoof that ant-hole."
Possibly cruel, but quite entertaining is pouring bicarbonate of soda solution down the ants' nest - the whole thing fizzes quite satisfyingly and the poor wee ants themselves sometimes exhibit a certain anal effervescence too.
There was a bloke on TV the other day who pours molten Aluminium down ant's nests. When it all cools down he digs it up and it looks really neat. A three-dee map of the nest. It also solves the ant problem in no small way. Like the powder, it isn't good for your skin.