Please help - ID this weed/bush
I was hoping that someone could help me ID this weed/bush as I have no clue what it is. There are two clumps of them thriving quite happily in my yard. Each one is about 9-10 feet tall and is currently in bloom. I can't really call it a bush because it's more like a clump of separate plants growing together. For some reason my landlord seems to think it's a pretty flower but it seems more like a weed to me. I know I don't want it around as it's choking out my other plants.
I have attached a link to a photo of the leaves with a flower as well to help ID it.
Any help would be appreciated.
Here is a link that might be useful: