Mistletoe in Trees: An Arborist’s Guide to Identification, Damage, and Proper Removal (by Tree Masters Tree Service of Dallas / Fort Worth)

What Is Mistletoe?

Mistletoe is a parasitic plant that grows on trees and shrubs, most commonly hardwoods such as oak, elm, hackberry, pecan, and maple, as well as some ornamentals. Unlike typical plants that grow in soil, mistletoe attaches directly to a tree’s branches and draws water and nutrients from the host tree.

In Texas and much of the southern U.S., the most common species is American mistletoe (Phoradendron).

From an arborist’s perspective, mistletoe is not just a cosmetic issue—it is a structural and physiological stressor that weakens trees over time.

How Mistletoe Infects Trees

Mistletoe spreads primarily through birds:

1. Birds eat mistletoe berries

2. Seeds pass through digestion or stick to beaks

3. Seeds are deposited on branches

4. The seed germinates and forms a haustorium (a root-like structure)

5. The haustorium penetrates the branch and connects to the tree’s vascular system

Once established, mistletoe becomes permanently embedded inside the branch wood.

Why Mistletoe Is a Problem (From an Arborist’s View)

Mistletoe causes both short-term stress and long-term structural damage:

1. Nutrient and Water Theft

• Mistletoe siphons water and minerals year-round

• Reduces resources available to leaves and new growth

• Accelerates decline during drought and heat stress

2. Canopy Dieback

• Infected branches often show:

  • Reduced leaf size

  • Sparse foliage

  • Early leaf drop

  • Dead tips

3. Added Weight & Breakage Risk

• Mistletoe clumps act like wind sails

• Increase limb failure during storms

• Common cause of branch breakage in older trees

4. Progressive Infestation

• One clump becomes many

• Infestations worsen every year if untreated

• Heavily infested trees often decline beyond recovery

In severe cases, mistletoe contributes to tree failure, creating a safety hazard for homes, driveways, and pedestrians.

Common Myths About Mistletoe

“If I cut the mistletoe off, it’s gone.” False. Cutting off visible growth does not remove the embedded haustorium.

“Mistletoe only affects weak trees.” False. Healthy trees can become infected and decline over time.

“Chemicals can kill mistletoe.” Mostly false. There is no reliable chemical cure that kills mistletoe without harming the tree.

Proper Arborist-Approved Removal Methods

Method 1: Structural Pruning (Best Practice)

The only reliable long-term solution is to remove the infected branch back to healthy wood.

Professional standard:

• Cut 12–18 inches below the visible mistletoe growth

• Make cuts outside the branch collar

• Use proper pruning techniques to prevent decay

Eliminates the haustorium - Stops regrowth on that branch - Improves tree structure and safety - This method is ideal for light to moderate infestations.

Method 2: Suppression (When Full Removal Isn’t Possible)

In large or mature trees where removing entire limbs would:

• Compromise structure

• Unbalance the canopy

• Create excessive wounds

Arborists may:

• Remove visible mistletoe growth

• Reduce canopy load

• Monitor regrowth annually

This does not eradicate mistletoe—it only slows spread.

Method 3: Topping or Improper Cutting (Not Recommended)

• Topping creates stress and decay

• Encourages weak regrowth

• Makes future infestations worse

This approach often shortens the life of the tree.

When Tree Removal Becomes Necessary

Complete tree removal may be recommended when:

• Over 50% of the canopy is infested

• Structural limbs are compromised

• Tree is already in decline

• Safety risks outweigh preservation

An experienced arborist evaluates risk, structure, and recovery potential before recommending removal.

Can Mistletoe Be Prevented?

While it can’t be fully prevented, it can be managed:

Annual inspections - Early pruning when clumps are small - Maintaining tree health (watering, mulching) - Avoiding stress from construction or soil compaction

Early intervention dramatically reduces long-term damage and cost.

Why Professional Arborist Care Matters

Mistletoe management is not a DIY job in most cases:

• Improper cuts damage trees

• Climbing hazards increase risk

• Incorrect pruning accelerates decline

A professional tree service:

• Identifies true infestation severity

• Uses ANSI-approved pruning standards

• Preserves tree structure and health

• Protects property and people

Arborist’s Bottom Line

Mistletoe is a parasitic plant that weakens trees over time, increases storm damage risk, and spreads rapidly if ignored. The only effective long-term control is proper structural pruning performed by a trained tree professional.

Tree Masters Tree Service can help

With 38 years of experience with DFW trees and landscapes, we have learned how to keep mistletoe under control by keeping your trees healthy with regular maintenance and checkups. In addition, we have had tremendous success with a broad-spectrum treatment that boost the trees vigor and vitality. We have found that the trees that are under our care and regular maintenance that have received these treatments have very little to no mistletoe. After noticing this, we purposefully tested many trees at many different locations throughout the DFW Metroplex to test our findings further. We are happy to report that annual treatments that keep your trees in tip-top shape also show to ward off mistletoe infestations.

Looking for professional tree care solutions at affordable rates? Call Tree Masters Tree Service at 972-261-7511 or visit us online at https://treemasters-tree-service.com to schedule a free consultation and/or estimate.

"We'll go out on a limb for you"