The mistletoe grows on trees and steals nutrients and water from the tree. It is a small, shrub-like plant that sends root-like organs called haustoria to the tree's cambium and hacks the tree's carbohydrates and sources of moisture.
If mistletoe grows wild it is a parasitic plant that attracts carbohydrates from the tree, this activity can reduce the health of the particular branch to which the mistletoe is attached and minimize the performance of the tree. In general, trees need to be cleaned of these parasites in order for the tree to remain in great health and splendor.