How to fix lawn with tree roots

If you see big roots exposed, curling or snaking on the soil’s surface around a tree, it can be a sign of trouble.

Tree roots normally grow just below ground, in the top 12 to 18 inches of soil. They spread much wider than most people realize, but they don’t stay on the surface unless they’re forced to. Roots can be exposed by:    

• Rain, runoff or wind may erode the soil around roots. This is especially common on slopes.
• Lack of space. The tree may simply not have enough space for its roots, if it’s hemmed into a small area by sidewalks, streets, and buildings. When a growing root encounters an obstacle, such as a foundation or a curb, it may be deflected to the surface.
• Where people trample a tree’s roots zone, they may wear away the soil or pack it down so far it exposes the roots.

When roots are above the soil, they’re easily damaged. They can be sliced by lawnmowers or string trimmers, or worn and torn by foot traffic. Damaged roots can’t do their job of collecting water and nutrients to support the tree.

Don’t try to rebury the roots by piling on more soil. The soil may end up too deep or tightly packed, so the fine feeder roots can’t absorb oxygen.

Do spread mulch over the roots. This will:

• Cushion the roots
• Insulate them
• Discourage foot traffic
• Keep lawnmowers away (there’s no need to mow mulch)

Do use an organic material such as wood chips or shredded wood. Spread it in an even layer 3 to 4 inches deep over the surface of the soil.

Do make the area of mulch as large as it needs to be to completely cover the exposed roots, even if that means covering an area of lawn. It’s healthier for a tree to be surrounded by mulch than by grass.

Don’t pile mulch against the bark of a tree; that can lead to rot or disease. Always spread it evenly. Be on alert. The mulch will decay over time. When it grows thin, you can add more mulch right over the old, as long as it never gets more than 3 to 4 inches deep.

Exposed roots aren’t just a dangerous tripping hazard; they can spell danger for the trees they support. Take steps to protect mature trees by protecting their roots with good cover and insulation and then stay clear so you don’t create problems by your well intentioned attention.

Photo courtesy of Bartlett Tree Experts.

Are ugly surface roots buckling your concrete driveway or stopping you from mowing your lawn? Before you get frustrated and cut them out, there are some things you need to know.

72tree.com gathered the following information on how to handle surface roots without compromising the health of your tree.

Why Do Tree Roots Surface

While some roots grow deep in the ground, the majority of them spread out from the trunk within the first 4 to 12 inches of soil. As the tree ages, several factors may bring them to the surface:

Erosion – Over time, the top layers of soil may be washed away, lowering the ground level, subsequently exposing tree roots.

Soil Compaction – As tree roots spread out, they seek moist aerated soil to derive water and nutrients. When they run into compacted soil, they will turn downward or upward, and in many cases will grow along or just beneath ground level.

Natural Growth – The same way a tree trunk and limbs increase their girth with age, so do roots. Since the majority of tree roots grow within the first few inches of soil, they tend to break the surface as they thicken.

Species – Some trees grow this way. Species such as maples, poplars, and willows tend to grow surface roots.

As annoying as it may be, surface roots are a common landscape problem that can cause significant and costly damage.

Surface Root Problems

When tree roots surface, there are many potential issues they bring with them. Those issues may include:

Disease, Infestation, and Rot – Surface roots are highly susceptible to being injured or damaged by landscaping equipment, foot traffic, or wildlife. Damaged surface roots are easily infected by disease, or infested by insects and can carry harmful pathogens to the trunk and branches of the tree.

Damaged Driveway or Sidewalk – As these roots thicken and surface, the ones that have grown under sidewalks, driveways, and foundations will eventually exert enough pressure to raise or break them.

Read more on how tree roots can buckle a driveway and what to do at 72tree.com/tree-roots-buckling-concrete-driveway/

Damaged Landscape Equipment – Lawnmowers and other mechanical equipment can be severely damaged when making contact with surfaced tree roots.

Abnormal Growth – Where Tree roots surface, any grass or plant life surrounding those roots may become sparse or die.

Trip Hazard – When surface roots are further exposed by erosion, they may become a severe trip hazard when navigating your landscape.

Surface Root Solutions

While cutting the roots away may seem to be the best alternative, it is not. Cutting away roots (like damaging them) leaves the tree highly susceptible to deadly diseases and infestation.

The following are ways to resolve surface root issues without causing severe damage to the tree:

Mulch – At the first sign of roots breaking the surface, lay down a 2 to 3-inch layer of organic mulch. Mulch will help the soil retain moisture, and over time may redirect the roots to grow downward.

Soil Replacement – In cases of erosion exposing roots, lay down a 3 to 4-inch layer of soil to replace what was eroded. To prevent further erosion, you can mulch the area around the tree, seed the new soil with grass, or lay down sod.

Plant Plants – Where erosion is not the problem, one solution may be planting the area with taller ground cover or plants that won’t need mowing. As you create this “tree root garden,” take care to avoid damaging the roots while planting.

If you are still inclined to have the roots removed, hire an arborist to do this for you. Depending on the damage that may have already occurred, and type of roots that will be removed, it may be suggested to remove the tree.

Surface Root Prevention

Avoid the inconvenience of surface roots by taking action before they come to the surface:

Planting Location – Each tree species has a preferred type of soil, light, and nutrients for healthy growth. By planting trees in optimal conditions for their species, roots will be less likely to surface as the tree ages.

Soil – The soil type, moisture level, nutrient content, and pH level affect how tree roots grow. Deep watering, seasonal fertilizing, and annual pH level adjustments will encourage tree roots to grow deeper.

Species – As mentioned earlier, some tree species are prone to grow surface roots. When selecting trees for your landscape or yard, be sure to ask about the tree’s growth patterns, and do your research on the species needs for optimal growing conditions.

Read more about tree planting and care at 72tree.com/tree-planting-guide/

Exposed Tree Root Solutions

Don’t let gnarly surface roots discourage you from having a beautiful landscape. There are ways to incorporate them in your design without fatally wounding your tree.

In this article, you discovered why tree roots come to the surface, the problems they can cause, and measures you can take to solve and prevent them.

Your mishandling or damaging of surface roots can lead to the health decline and death of your tree. Before you cut roots away, call a professional to evaluate the situation and offer alternatives to save your landscape and your tree.

Sources:
https://extension.umd.edu/hgic/topics/surface-roots
https://www.purdue.edu/hla/sites/yardandgarden/when-tree-roots-surface/

All trees have roots, but they are often something a homeowner doesn’t have to think about because they are hidden underground. But what about when roots appear above ground? It’s a problem we see often throughout Fairfield County and is more than just an eyesore. Exposed tree roots are a tripping hazard, they’re easily damaged (making them an easy access point for diseases and insects), and they frequently ruin lawn and landscape equipment. So, what can you do to fix exposed tree roots?

In this article, we cover:

• what causes exposed tree roots,
• how exposed tree roots can lead to larger issues,
• what you can do about exposed tree roots,
• what you should avoid when dealing with exposed tree roots,
• and more!

How Tree Roots Grow

A tree’s roots are its lifeline, even if those roots are growing above ground. Roots seek out water and nutrients from the soil to support tree growth. Wherever they find these, trees will send roots growing in that direction.

Many people are surprised to learn that most tree roots grow only in the top 4” to 20” of soil. That’s where there are enough oxygen, moisture, and nutrients to support the tree. And, although a tree’s drip line (the edges of its leafy canopy) is usually considered the edge of a tree’s root zone, a tree’s root system often spreads far wider.

The bottom line is that you can’t expect a tree’s roots to stay within a confined area or to grow only downward.

Why Tree Roots Grow Above Ground

Exposed tree roots happen for several reasons.

• Environmental conditions. Over time, rain falling on bare soil will compact it. This creates a crust that doesn’t absorb water, leading to water runoff instead of soaking down to where roots (should) grow. Rain will also erode and wash away bare soil, leaving roots exposed. And the soil in windy locations will often be scoured away from around tree roots.
• Too little space for roots. When trees are planted in small areas, their roots don’t have enough room to expand naturally. In an attempt to find water and nutrients, the roots will grow out of the soil and spread along the surface.
• Impervious surfaces surrounding the tree. When the areas surrounding a tree are made of concrete or other impervious materials (such as in a planting pit), roots won’t find oxygen and water beneath them. Additionally, the soil beneath sidewalks, roads, driveways, and foundations is heavily machine compacted, making it difficult for roots to grow.
• Heavy traffic areas. If a tree’s roots are growing in areas that are used by both pedestrians and vehicles, surface soil will wear away and become compacted from use. Any roots that were growing near the surface will become exposed as the soil around them wears away.
• Soil compaction. Whether the soil is compacted from rain falling on it, from vehicles driving and parking on it, or from construction, it creates conditions that are difficult for roots to grow in. When roots can’t grow down through dense soil, they grow at the surface where it’s easier to find oxygen and water.
• Tree species. Exposed roots are common in some species of trees. Often, shallow root development is the result of a tree having evolved in moist or wet growing conditions. Below are three common examples:
• Maples (Acer) naturally develop dense, shallow, fibrous root systems. These help the trees find water and nutrients in shallow and rocky soils.
• Poplars (Populus) are tall trees that develop extensive, spreading root systems. They often grow near water sources and so tend to have shallow roots. New poplars sprout from existing root suckers near the soil surface.
• Willows (Salix) grow in wet areas and have aggressive and extensive root systems. When planted in the right place, such as near waterways, these roots help stabilize stream banks by holding the soil together.
• Tree age. As a tree matures and grows, its root system is also spreading in an effort to find water and soil nutrients to support the growing tree. As these roots grow and age, they expand in diameter and become tough and woody. A small root growing near the surface will break the soil’s surface as it becomes thicker. If the soil around tree roots is eroding or becoming compacted, the root will break the soil surface sooner.

Why Exposed Tree Roots Are a Problem

• Tree roots are easily damaged. For example, foot traffic, vehicles driving over or parking on roots, and mowers and string trimmers can all damage roots. When roots are injured, they can no longer do their job of transporting water and nutrients from the soil to all parts of the tree. This stresses the tree and can lead to branch and leaf dieback.
• Damaged roots are vulnerable to diseases and insect pests. Like a bark wound, an injured root creates an opening for insects or diseases to get inside and damage a tree’s entire system. This can lead to expensive tree problems for a homeowner, including tree removal.
• Exposed tree roots can also cause damage! Garden tools can be damaged by protruding roots, and exposed roots can also become a tripping hazard to pedestrians. It can take less than an inch of root sticking out from the soil to trip someone who’s walking.

How to Deal with Exposed Tree Roots

First, understand WHY the roots are growing above ground. It may be due to an issue that you can fix but, almost as often, the cause isn’t something you can change. In those cases, it may be best to simply remove the tree if the exposed roots are a problem.

Next, learn what you can and cannot do to remedy issues with roots growing above ground. Doing the wrong thing can result in worse problems than just having an unsightly tripping hazard on your lawn!

What NOT to Do When Roots Grow Above Ground

• Bury roots with more soil. A tree that’s already growing should never have the soil level around its roots changed. Burying roots may hide them from your view but you’ll suffocate the roots, killing them and stressing your tree. When you kill roots, you’re cutting off the established lifeline of water and nutrients that the tree depends on.
• Pave over roots. Paving over exposed tree roots is like covering them with soil, only worse. If you pave over tree roots, those roots will die and decompose. As they do, they will make your paving base shift, causing the surface to become uneven and unstable. Now your paving will be a tripping hazard, too!
• Cut off tree roots. You should never cut exposed tree roots. Don’t be fooled by tough, woody roots that might look dead! They’re all alive and never go dormant. An exposed cut root is like a badly pruned branch; it can’t recover.
• Cover roots beneath a mulch volcano. Mulch is an important part of a healthy garden, but only when it’s in the right place. Never pile mulch up around the trunk to hide exposed roots (mulch volcanoes are a leading cause of tree death!). Always keep mulch away from the base of your tree’s trunk.
• Disguise exposed roots under a new planting bed. Keep any new planting areas at the tree’s drip line or beyond. Digging in the important root zone around a tree is extremely damaging and can kill the tree. Plus, adding new plants around an existing tree also creates more competition for water. You’ll have healthier trees that live longer if you plant annuals and perennials in separate areas and leave the soil around your tree undisturbed.

What You SHOULD Do With Exposed Roots

• Cover exposed roots with a layer of organic mulch. This is a good solution when the lawn is growing beneath a tree and struggling. A tidy, even circle of mulch beneath a tree’s crown is an easy way to resolve tree root and turfgrass conflict; mulch will protect roots and kill the grass. Just be sure to keep mulch pulled well back from the tree’s trunk.
• Fix compacted soil. Compacted soil is a major cause of both exposed tree roots and poor tree health. If you have compacted soil, have it repaired professionally. The best (and least damaging) way to improve compacted soil is to use an airspade around a tree’s roots to loosen the soil, incorporate compost to add nutrients, and then fill it back in. Ideally, you’d then spread a layer of wood chip mulch out to the drip line to eliminate future compaction. Or compromise with a mulch ring around the tree with grass seed (or sod) farther away.

NOTE: Many homeowners want to replace lawn beneath their trees after soil aeration. It’s important to remember that shallow lawn irrigation is a major cause of exposed tree roots, and that heavy lawn equipment like mowers both cause exposed tree roots and make them worse.

How to Prevent Roots From Growing Above Ground

People sometimes turn to root barriers as a way to stop roots from spreading above ground. However, root barriers are only a temporary fix. Root barriers may send some roots away from where they aren’t wanted, but they’re not a solution to tree root problems and won’t fix existing exposed roots. And excavating soil to bury a root barrier can make roots want to grow there because the soil is loose and there’s lots of water and oxygen.

However, there are some things you can do to limit the likelihood of roots growing upwards.

• Plant the right tree in the right place. Trying to fit a big tree in a small planting area ensures future root problems. Choose the right tree species for your soil and the size of your garden. Need help choosing the right tree? We’re here to help.
• Water your tree properly. Roots grow in search of water, so make sure to irrigate your trees “low and slow” so water soaks down into the soil. Roots will follow the water.

Exposed Tree Roots? Give Us a Call!

Contact the arborists at Rayzor’s Edge Tree Service for a tree consultation if your tree’s roots are growing in the lawn, cracking the walkway, or tripping passersby. We can determine what’s causing your tree’s exposed roots and recommend the best way to remedy the problem.

Related