Understanding Tree Root Systems and Their Impact on Your Property
When people think of trees, they often focus on the parts above ground—leaves, branches, and flowers. But what lies beneath can be just as important. Tree root systems play a major role in the tree’s health—and in how it interacts with your home, driveway, and landscape. Here’s what every homeowner should know.
1. Types of Tree Root Systems
Most trees have one of the following root systems:
Taproot System: A dominant central root that grows deep into the soil (rare in mature trees; found in seedlings and some species like oaks).
Fibrous Root System: A network of shallow roots that spread widely (typical in many landscape trees).
Heart Root System: Roots grow both vertically and horizontally, creating a compact, stable base.
Important: Over 90% of tree roots are in the top 18–24 inches of soil and extend 2–3 times wider than the canopy.
2. How Roots Affect Your Property
A. Sidewalks, Driveways & Foundations
Roots don’t “seek out” concrete to damage it—but if there's a crack or weakness, expanding roots can exploit it.
Shallow-rooted species like willow, silver maple, and sycamore are more likely to lift pavement.
B. Underground Utilities
Roots can grow into sewer lines, especially if there's a leak attracting moisture.
Always call 811 before digging near trees to avoid damaging roots or hitting lines.
C. Lawn Health
Tree roots compete with grass for water and nutrients.
Shade from the canopy combined with surface roots often leads to patchy lawns beneath mature trees.
3. Tree Root Myths—Debunked
✅ Myth: Tree roots grow deep and straight down.
Reality: Most roots spread wide and shallow.✅ Myth: Cutting a few roots won’t hurt a mature tree.
Reality: Removing major roots can destabilize the tree or trigger decline.
4. Best Practices for Managing Roots
Choose Wisely
Select species with non-invasive roots if planting near hardscapes.
Good choices: Crepe myrtle, redbud, dogwood
Avoid: Willows, silver maples, sycamores near buildings
Mind the Distance
Plant large trees at least 20–30 feet from foundations or driveways.
Small ornamentals can be planted closer, around 10–15 feet away.
Use Root Barriers (When Necessary)
Installed between a tree and structure to redirect roots downward
Best used during planting—not a fix for existing root issues
Don’t Over-Prune Roots
If construction or trenching is unavoidable, consult an arborist.
Never cut roots closer than 3–5 times the trunk diameter from the tree.
5. Healthy Roots = Healthy Trees
Support strong root systems with:
Mulch – Keeps soil moist and reduces compaction
Avoiding soil compaction – Don’t park cars or store heavy equipment under trees
Proper watering – Deep, infrequent watering encourages deeper roots
Final Thought: A tree’s roots are its foundation. Respecting their growth habits and needs will help you maintain a safe, beautiful, and lasting landscape.