Mistletoe is a familiar sight of the season, often found wrapped in ribbon and hung for certain festivities this time of year. But did you know it is actually a parasitic plant that grows on a number of landscape trees in California?

There are two types of mistletoe in California. Broadleaf mistletoes attack certain broadleaf trees and some conifers while dwarf mistletoes attacks only conifers. Broadleaf mistletoes have green stems with thick, oval leaves. Dwarf mistletoes are smaller, with short stems and yellow scaly leaves.

Both types of mistletoe grow through tree bark and into the tree's tissue, living off the host tree. Healthy trees can typically tolerate a few mistletoe infections although individual branches may...