It's Hendera helix, English ivy, with the adult foliage. Once the plant has climbed to a certain height it will produce the adult foliage and not the juvenile lobed leaves.

are you sure the hedera is killing the tree? What sort of trees?
Black birds feeding on the flowers? don't you mean on the berries...

aswhad - Hedera helix is an invasive species in the US - it doesn't have the ecological niche there that it does in Europe and is considered a real nuisance. Insects love the flowers and birds love the berries. But, like you, I've never seen birds eat the flowers. Ivy doesn't kill trees per se - it is not parasitic - but it can smother the foliage and cut down the light or act as a sail in windy weather causing weak trees to fall.

Yep. that sure looks like adult leaves of Hedera helix. It produces yellowish flowers which yellow jackets love, and black fruit that birds love. As florauk says, it can overwhelm and smother a tree. We had this growing up a flowering dogwood when we bought our house - some of the stems were almost as thick as the tree branches. I cut the stems at their base and let the ivy die - took persistence and was kind of unsightly for a while before the ivy leaves fell off, but now it's gone for the most part and the dogwood is doing much better.