That just goes to show you that there is so much plastic blowing around in nature that a grey blob in the tree immediately brought to mind a plastic bag.
Not a wasp nest.
Which is exactly what it is. How did that thing grow so fast and never get noticed? Especially when it can clearly be seen from our back windows? Obviously, the leaves sheltered it from view until they parted ways with the tree a week or so ago.
It's so high up in the tree I'm not sure we could have done much anyway. I think it's there for the duration. Although it was warm and sunny when I took the photos I never saw a sign of a wasp. But my mind is imagining just how many wasps a nest that size could hold. Pollinators, right? All part of a healthy ecosystem....