Driveways or parking lots are major investments, and while you might focus on weather and traffic as the main threats to your asphalt, there’s another silent factor beneath the surface: tree roots and the impacts of landscaping. 

Understanding how these issues interact with your asphalt can help you protect your investment and avoid costly repairs down the road. To help, this article explores warning signs and preventative measures you can take.

The Impact of Tree Roots

As tree roots grow and expand in search of water and nutrients, they can exert significant pressure on anything in their path, including asphalt. A mature tree’s root system can extend two to three times beyond its canopy, meaning that even trees planted several feet away from your driveway or parking lot can eventually cause problems.

For example, let’s say you plant a tree 15 feet away from your driveway, thinking that’s plenty of space. As the tree matures and its canopy grows to 10 feet wide, those roots could be stretching 20 to 30 feet from the trunk. That means they’re potentially reaching under or even past your driveway.

The damage often starts small. You might notice slight ripples or bumps in your asphalt surface. Over time, these minor imperfections can develop into significant cracks, upheaval, and even complete surface failure. Once tree roots lift or crack your asphalt, water can penetrate the base layer, accelerating deterioration and leading to potholes and further structural damage.

Common Landscaping Culprits

Tree roots aren’t the only issue. Several landscaping features can also be damaging to asphalt. These include:

Irrigation systems positioned too close to asphalt edges can oversaturate the soil, weakening the base and causing the pavement to shift or sink. In fact, water is one of asphalt’s biggest enemies, and consistent exposure to moisture from sprinklers or drainage issues creates the perfect conditions for base erosion.

Decorative plantings along driveway edges might look attractive, but they require regular watering that can seep under asphalt. Meanwhile, aggressive ground covers and plants with invasive root systems can work their way beneath and through small cracks in your pavement.

Poor drainage from landscaped areas can direct water flow toward or under your asphalt surface, which can be another factor. That is particularly problematic in Southern Arizona, where intense monsoon rains can overwhelm inadequate drainage systems.

Warning Signs of Asphalt Damage

You can save a significant amount of money on repair costs by catching problems early. Here are some red flags to look for:

  • Visible cracks running parallel to trees or landscaped areas
  • Raised or uneven sections of asphalt near vegetation
  • Standing water or soft spots along the edges of your pavement
  • Buckling or warping in specific areas
  • New cracks that appear after seasonal growth periods

Preventative Measures to Consider

Fortunately, you’re not powerless. With proper planning and maintenance, you can extend the life of your asphalt and protect your investment. Consider the following preventative measures:

Strategic tree placement: When planning new landscaping, plant trees at a safe distance from your asphalt to prevent damage. Usually, this is at least 10 to 15 feet away, depending on the mature size of the tree species. Consult with a landscaping professional to choose species with less aggressive root systems.

Install root barriers: These physical barriers, located between existing trees and the asphalt, redirect root growth downward rather than horizontally toward the pavement. While not foolproof, they can significantly reduce the risk of root-related damage.

Maintain proper drainage: This is crucial to ensure that water flows away from your asphalt surface. It might involve adjusting irrigation systems, installing French drains, or regrading landscaped areas to direct water appropriately.

Regular sealcoating: This creates a protective barrier that helps prevent water penetration and can slow the progression of minor damage. At Sunrise Asphalt, we recommend sealcoating every two to three years to extend the life of your asphalt and protect against various threats, including moisture from nearby landscaping.

When to Call Professionals for Help

Early intervention is always more cost-effective than major repairs. Therefore, knowing what to watch for and acting promptly at the first signs of damage is crucial.

At Sunrise Asphalt, we understand the unique challenges that Arizona’s climate and landscape present. Our team can evaluate your property, identify potential problem areas, and develop a maintenance plan that protects your investment while preserving your beautiful landscaping. Contact us today to learn more.