After the leaves fell from our maple tree, a clump was left near the top. I have decided it must be mistletoe.
"From the centre of the ceiling of this kitchen, old Wardle had just suspended with his own hands a huge branch of mistletoe, and this same branch of mistletoe instantaneously gave rise to a scene of general and most delightful struggling and confusion; in the midst of which, Mr. Pickwick, with a gallantry that would have done honour to a descendant of Lady Tollimglower herself, took the old lady by the hand, led her beneath the mystic branch, and saluted her in all courtesy and decorum."
--The Pickwick Papers by Charles Dickens
Mistletoe, a parasitic plant that is toxic to humans but provides nutrition for birds, butterflies and some mammals, is traditionally used at Christmas above a doorway so that anyone caught standing under it might get kissed.