Tree Care and Maintenance

Seasonal Tree Care Tips: Spring
Protecting Your Trees: Why Lawn Equipment Causes Damage and How to Prevent It

Photo Credit: International Society of Arboriculture, Bugwood.org

Trees are one of the most valuable features in any landscape, offering shade, beauty, and environmental benefits. Yet one of the most common threats to their health comes from an everyday source—lawn mowers and string trimmers.

Why Lawn Equipment Is Harmful to Trees
The base of a tree, where the trunk meets the soil, is especially vulnerable. This area contains thin bark and vital tissues responsible for transporting water and nutrients. Even minor contact from a mower or repeated hits from a string trimmer can cause significant injury. These wounds, often called “mechanical damage,” expose the tree to pests, diseases, and decay. Over time, repeated damage can girdle the tree (cutting off nutrient flow), weaken its structure, and even lead to death. Young trees are especially at risk because their bark is thinner and less protective. Signs of damage can include:

  • Missing or shredded bark at the base of the trunk
  • Visible scars or darkened wounds
  • Leaning or declining growth over time

What Property Owners Can Do
Fortunately, preventing this type of damage is simple and highly effective. Here’s what you can do:

  • Create a mulch ring. Apply a 2- to 4-inch layer of wood chips or bark around the base of the tree, extending at least a few feet out. This eliminates the need to mow or trim close to the trunk while improving soil health.
  • Avoid piling mulch against the trunk. Keep mulch a few inches away from the bark to prevent moisture buildup and rot.
  • Keep equipment at a distance. Treat the mulch ring as a “no-mow zone.” This is one of the easiest and most impactful changes you can make.
  • Use physical guards if needed: Tree guards or trunk protectors can provide added protection, especially for young or newly planted trees.
  • Educate anyone maintaining the property. Whether it’s family members or a landscaping crew, make sure everyone understands the importance of protecting tree trunks.

A Small Change Equals Big Impact
Preventing mower and trimmer damage is one of the simplest ways to extend the life of your trees. With a little awareness and a few practical steps, property owners can protect their landscape investment and help trees thrive for years to come.

 

Learn more about protecting trees from mechanical damage by visiting these resources:

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Archives

Winter 2026: Start Smart: What to Consider Before Planting a New Tree

Fall 2025: Invasive Plants

Summer 2025: Heat Stress and Sunscald

Spring 2025: Trees for Bees…and Other Pollinators, Too

Winter 2025: Fruit Tree Maintenance

Fall 2024: For a Healthier Yard, Leave the Leaves

Summer 2024: Tree Risk Assessment

Spring 2024: Invasive Ivy Removal

Winter 2024: Clean and Sharp Pruners

Fall 2023: Mediterranean Oak Borer

Summer 2023: Supplemental Watering and Mulch to Prevent Drought Stress in Trees

Spring 2023: Aphids

Winter 2023: Pruning: Standards and Best Practices

Summer/Fall 2023: Emerald Ash Borer

Winter/Spring 2022: Nesting Season

Fall 2021: Healthy Trees are Defended Trees

Special Edition: After the Storm

Winter 2021: What is an Arborist?

Fall 2020: Soil Management  

Summer 2020: Retaining and Creating Snags for Wildlife

Spring 2020: Mulch: Numerous Benefits and Easy Application

Winter 2020: Tree Planting: To Stake or Not to Stake?

Fall 2019: Insects and Diseases

​Summer 2019: Drought Stress Revisited

Spring 2019: Trees and Construction

Winter 2019: Topped Tree

Fall 2018: Autumn Leaves

Summer 2018: Emerald Ash Borer

Spring 2018: Pruning Young Trees

Winter 2017: Tree Related Storm Damage

Fall 2017: New Tree Selection and Planting

Summer 2017: Trees and Turfgrasses

Spring 2017: English Ivy Removal

Winter 2017: Recognizing Tree Risk

Summer 2016: Drought Stress

Fall 2016: Preparing Trees for Winter

 

Additional Tree Care Resources:
 

National Arbor Day Foundation The Morton Arboretum
Oregon Department of Forestry Tree Care Info
ISA Find an Arborist Alliance for Community Trees
Oregon Department of Forestry  

 

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