Mistletoe

Even though I had never seen wild mistletoe before I knew what this was as soon as I saw it. I'm not sure how long the mistletoe has been there, if it grows quickly or if the leaves had just been hiding it until now.
While I couldn't truly have a positive ID due to not actually knowing much about the plant these are the few things I noticed right away and are pretty much give-aways.
1) It's parasitic. This bunch seemingly popped out of a tree branch without any roots, vines, etc. It's called a pendant bush, which is pretty self-explanatory.
2) Bunches of white berries.
3) Leathery, ovate leaves with rounded tips. Also referred to as "tongue shaped."

Mistletoe doesn't have to be a parasite, but that's how it's most commonly found. It does have roots, but these roots like to go into live branches as well as soil. The entire plants grow between 2-5 feet.
The leaves are thick, 1-3 inches long, and grow in pairs. The fruit grow in bunches of up to 10 berries. The flowers are small, inconspicuous, grow in sets of three, and appear in spring, the berries ripen in December.

There are so many interesting stories and myths about mistletoe. There's the story that mistletoe used to be a tree until it was used to make Christ's cross and was blighted into a parasite. There's also the one about Loki and Frigga, and the superstition that it conferred fertility. You should look it up, there's more about mistletoe than I could fit into a reasonable blog post.