Pathologist's Corner: Mistletoe

December 2007
By: Kevin Bassett & Russell Peters, Plant Pathologists, Certified Arborists

Mistletoe

Mistletoe is a parasite that derives its nutrients and moisture from a host plant. Mistletoe infections, left to develop in a tree, reduce the tree’s health overtime and can lead to weakened areas in larger limbs potentially resulting in limb failure (breakage). Once the mistletoe plant matures, seeds are produced which spread throughout the tree’s canopy, causing multiple new infection sites. Mistletoe management should be directed toward the removal of entire branches or twigs infected with mistletoe. When large limbs or limbs critical to the structure of the tree are infected, the mistletoe should be removed leaving the essential limbs. However, regrowth will occur throughout the year. On average, mistletoe removal will be necessary every two to three years as part of a regular tree maintenance program. This will address regrowth of old infections as well as new infections that will constantly occur on susceptible species. The North Texas area has a number of susceptible species, many of which are growing in our residential landscapes. Cedar Elm by far is the most susceptible high value species where we see mistletoe infections. Some of the other species include American Elm, Hackberry, Mulberry, Ash and Bois D’ Arc. Winter is also a common time for new infections to occur, as birds will consume the fruit that has now matured, and deposit seeds throughout the canopies of susceptible species.

North Central Texas has a number of susceptible species, many of which are growing in our residential landscapes. Cedar Elm is by far is the most commonly infected tree species. Other susceptible trees include American Elm, Hackberry, Mulberry, Ash, and Bois D’ Arc.

Mistletoe can be removed at anytime of the year. However, it is more visible during the dormant season, and in most cases more easily removed during this time of year.

EXAMPLES OF MISTLETOE

	Mistletoe is a parasite that remains evergreen. It’s nearly translucent white berries ripen after the yellow flowers bloom from fall into winter.
Mistletoe, Leaves and Fruit Courtesy of British Wild Flowers
Mistletoe is most commonly transported by birds after they have ingested the berries and roosted in a tree. Here are two examples of what mistletoe can look like in your tree from a distance. The best opportunity to remove mistletoe is in the fall when it is most visible.
	Mistletoe in Your Yard
	Mistletoe can grow on a single limb or the trunk, which can make the removal difficult and time consuming.
Invasive Mistletoe

Please call one of our qualified ISA Certified Arborists to assist you in mistletoe removal.

The information on this page & its associated links is owned by Arborilogical Services, Inc.
©Copyright 2007 by Arborilogical Services, Inc. No Reproduction is permitted in whole or part without the express written consent of Arborilogical Services, Inc.

Pathologist's Corner: Mistletoe

Arborilogical Services, Inc. Publication

Pathologist's Corner

Mistletoe

EXAMPLES OF MISTLETOE

Arborilogical Services, Inc.
Publication