What i know of Misstletoe is the seeds germinate and the plant grows
into the vascular tissue of the tree, which cuts off food and water
supply. I think if it's not too severe you could probably prune out
the branch with the parasite. I've heard in severe cases, it can kill
a tree.


Please explain what you mean when you say food?

Sincerely,
John A. Keslick, Jr.
Arborist
http://home.ccil.org/~treeman
and www.treedictionary.com
Beware of so-called tree experts who do not understand tree biology.
Storms, fires, floods, earthquakes, and volcanic eruptions keep reminding us
that we are not the boss.