Burning Grass – Removing Thatch with Fire

Stuart Wellbert
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What Is Thatch And Why Do I Need To Remove It?

The most common cause of thatch is that grass is not mowed at the correct height. Thatch is caused when the grass is mowed too short. The grass is cut repeatedly at the same height, eventually forming a dense mat. In addition, thatch is caused by decomposing grass that normally breaks down. However, when the grass is cut too short, and turns into a dense mat over time, it becomes its own fertilizer, and grass that decomposes has a high nitrogen content. This can cause large clumps of thatch to form over time. Imagine driving your car on grass that is 3” high. After a few passes, the lawn mower blades would be clogged with a dense mat of grass. When a lawn gets that dense, you would have to remove the thatch to help the grass decompose faster.

A thick layer of thatch in your lawn can be harmful for your grass. The grass is smothered, which slows its growth. This will inhibit the uptake of fertilizers and water, thus slowing grass recovery from damage or stress. You may also want to consider aerating the lawn to get rid of hard and compacted soil.

It is not recommended to burn the thatch layer, as this is typically where the root system and the soil develops. High temperatures could kill the roots and you will have to re-sod, or fertilize the lawn to stimulate new growth.

Thatch is thatch. A thatch is a layer of dead roots, stems, and sometimes leafs that form over time on top of the soil underneath your grass. There's nothing exotic about thatch. In fact, grass thatch is the natural result of healthy grass that grows vigorously. Healthy roots are full of carbohydrates. As they fall over and die, they form a mat of organic matter.

Thatch grows naturally. It is a good thing, but too much thatch can interfere with the ability of your grass to grow properly. A good, deep watering causes thatch to decompose and improve the health of your lawn. That’s why most thatch is a result of lack of water.

Thatch can be a nuisance for several reasons. Some grass types, like Bermuda, are naturally very thatchy. Thatch grows thicker in the winter months. But, thatch can be a real problem when it prevents water and soil from penetrating into the root zone.

In some cases, your lawn may have too much thatch without being thatch-prone. Thatch can be caused by a variety of reasons, including:

  • Overfertilization
  • Spiking Growth due to warm, wet, weather
  • Dramatic changes in the water supply of the lawn

How To Prepare To Burn Grass?

When you burn around your trees, you want to do it before it’s too humid. If you do burn in the heat, it’s a good idea to have a misting hose available. The water will help keep the fire from flaring up uncontrollably.

For under Your Deck

To get the best results from a fire, you’ll want to wait for a day that is at least 90 degrees. The higher the temperature, the better.

7 to 10 days before the first fire: Apply a thin layer of straw, dry mulch or wood chips. This should cover all of the grass in your area.

After the first fire: put down a layer of sod.

5 days before the second fire: Burn the area for the second time.

After the second fire: Scoop the ashes, put them in a trash bag and throw it out.

Patio

For the patio, you’ll need to burn every other week for 14 weeks. This means you can let the first fire die out on its own, and start from scratch with the second fire. There are no benefits to dividing your garden into areas to burn. You’ll be just as satisfied if you keep a steady pace.

How To Burn Grass To Remove Thatch?

If you’ve ever gone to mow the lawn and are stopped in your tracks by the sight of tall wet grass, you know that you have a little more work ahead of you than you had hoped. Saturated lawns are more likely to grow the grass above its normal height in order to get air to the roots. Because of this, grass becomes extremely dense. The top is nice, while the bottom may be up to three inches of, or even more, thick wet dirt.

This problem is known as thatch. Thatch is really no more than the grass plant that has blown out of shape. It’s caused by excessive fertilizer, moisture, or simply overgrown grass.

While methods such as aeration can help reduce thatch, there is another product that can help, fire.

Backburn

Backburning, or backfiring, a fire is when you ignite combustible material from the rear of a fire you are trying to extinguish. It works much like a blowtorch. It has the effect of “blowing out” the fire, and stopping air from feeding the fire.

Thatch is thatch. A thatch is a layer of dead roots, stems, and sometimes leafs that form over time on top of the soil underneath your grass. There's nothing exotic about thatch. In fact, grass thatch is the natural result of healthy grass that grows vigorously. Healthy roots are full of carbohydrates. As they fall over and die, they form a mat of organic matter.

Thatch grows naturally. It is a good thing, but too much thatch can interfere with the ability of your grass to grow properly. A good, deep watering causes thatch to decompose and improve the health of your lawn. That’s why most thatch is a result of lack of water.

Thatch can be a nuisance for several reasons. Some grass types, like Bermuda, are naturally very thatchy. Thatch grows thicker in the winter months. But, thatch can be a real problem when it prevents water and soil from penetrating into the root zone.

In some cases, your lawn may have too much thatch without being thatch-prone. Thatch can be caused by a variety of reasons, including:

  • Overfertilization
  • Spiking Growth due to warm, wet, weather
  • Dramatic changes in the water supply of the lawn

How Does Burning Grass Remove Thatch?

Thatch is the layer of dead grass and old roots that develops below the surface of the grass and can be a problem for golfers. To remove thatch, it takes the right tool. Manually pulling thatch out of the ground can be slow, difficult, and will leave excessive damage in the lawn. The best way to remove thatch is by burning.

Burning thatch allows the grass to stay green, and opens the dormant grass cells to new water. Burning also allows for the grass to come back quicker and stronger than if it was removed with a rake.

To get the most out of burning thatch, you have to burn at the right time and reapply the proper amount of fertilizer. To do this, you’ll need to burn no higher than three inches from the ground and when you apply fertilizer, don’t use excessive amounts.

To determine the right time to burn, take note of the color of the grass. The “greenness” of the grass is an indicator of the amount of nutrients the grass has. The greener the grass, the more burn it can handle.

Getting rid of thatch is a great way to improve your lawn without having to use harmful chemicals to yield the best results. Burning removes thatch, opens up grass cells for nutrients and water, and allows the grass to grow stronger.

Is There Another Way To Remove Thatch?

If you are not ready to burn your grass for hay or because you want it removed, we’ve got a couple alternatives. Thatch is the layer of grass that has withered and no longer serves the purpose of insulating the roots. Vigorous raking can be very effective, but so can other methods of taking out thatch from your lawn.

You can kill thatch with herbicides but you should be very careful and follow the instructions precisely. This will take some time to kill thatch deep down in the soil.

Are there other alternatives? Absolutely! Slicing the grass with a mower set at a higher axle height will also remove thatch by shaving off the top layer. This can be done periodically as a maintenance practice but should not be your only plan for removing thatch if there is a large amount of it. Letting the thatch build up over time can cause issues in your lawn, including moisture retention and poor aeration.

Benefits Of Burning Grass

Thatch is another reason why burning grass is a good idea. What is thatch?

Thatch is an accumulation of dead grass and roots leftover from the previous year. Thatch is a problem with grass lawns because it doesn’t allow air to travel into the root zone, and can keep the grass from being able to receive the necessary nutrients and water it needs. Burning the thatch layer can help your grass live a healthier, greener life.

This is a misconception though, as it is only part of the reason why burning grass is a great idea. Many people believe thatch helps the grass for some reason, but the reality is that it keeps the soil from draining properly and can lead to a host of problems.

Burning grass is the best way to remove thatch, but you will likely have to do it every year. Burning grass will allow for more sunlight and air to reach the roots, which will allow them to grow better and fight off diseases better. Burning grass is a great way to prevent future growth of thatch, but it won’t completely remove it from your grass.

Can I Burn My Grass?

You can, but only if you’re willing to consider the environmental implications.

Why does thatch build up in the first place? The answer is excessive thatch is caused by the accumulation of three things: ornamental grass clippings, decaying thatch and thatch-producing turf species. It’s the third aspect I’m concerned with here.

Many turf-type varieties of grass develop extensive rhizomes (underground stems) and coarse, thatch-producing blades. They are also often referred to as warm-season perennial grasses, and include such popular varieties as bermudagrass, buffalograss, centipedegrass, St. Augustinegrass and zoysiagrass, as well as roots from more drought-tolerant warm-season grasses like bermudagrass, buffalograss, centipedegrass and St. Augustinegrass. They all grow from seed and can produce thatch that has to be removed to keep the lawn healthy.