What is mistletoe and why does it grow randomly of trees?

A mistletoe is a leathery-leaved parasitic plant that grows on apple. oak, and other broad leaf trees.

Mistletoe is a everygreen shrub that is semi parasitic on other plants. Instead of producing roots in the ground, mistletoe sends out roots like stuctures into treebranches, from which it steals water and nutriens. The tree mitletoe grows upon is known as its host