Getting Rid of Unwanted Bermuda Grass Lawns
If you have a lawn you probably know from experience how much water is consumed by thirsty grass. But did you know lawns typically use twice the amount of water than the same size area planted in desert landscaping.
Maybe it's time to get rid of your lawn in favor of some low water use desert plants. There are many types of attractive, low water use ground covers that can be planted in groupings to create drifts of attractive foliage and flowers. They can be used alone or with varieties of native and desert-adapted shrubs.
The best time to remove a bermuda grass lawn is in the heat of summer. Bermuda is most vigorous in hot weather and is therefore much more susceptible to eradication with chemical herbicides.
The herbicide of choice to kill bermudagrass is glyphosate, most commonly sold under the trade name Roundup. It has systemic properties and as such has the ability to kill grass plants, roots and all. This is very important for eradicating bermudagrass which tenaciously comes back from any vegetative parts not killed. Glyphosate is absorbed by the leaf blades and transported down into roots, stolons, and rhizomes killing them and preventing regrowth.
Treating the Lawn
Prior to treating the lawn, make sure it is growing healthy. A week or so prior to spraying the grass with glyposate, fertilize it to stimulate growth. Use an inexpensive, high nitrogen fertilizer such as ammonium sulfate (21-0-0). Apply 5 pounds of ammonium sulfate per 1,000 square feet of lawn area and water it in. Keep watering as you would normally. Allow the grass to grow and do not mow it. The longer the leaf blades, the more efficiently glyphosate will be absorbed. Continue to water the lawn normally until you are ready to apply the glyphosate.
When applying any chemical follow all label directions. Never apply a chemical pesticide higher or lower than the recommended rate. A lower than recommended rate of glyphosate will not be enough to be absorbed and move into the roots. A higher rate than recommended will have much the same effect. The grass blades will die too soon and the chemical will not be moved down to the roots.
The best time to apply the glyphosate is from early to mid-morning. The spray should be on the grass a minimum of 3 hours prior to an irrigation or rain event. Water falling on the grass too soon after application will wash some of the chemical off. Also be sure to apply the spray to dry leaf blades. If your irrigation comes on at night or in the early morning, wait until the grass blades have dried before applying glyphosate. Put on enough spay to wet the grass blades, but not so much that it runs off. It will also help increase the effectiveness of the spray to add a spreader-sticker to the spray mix prior to application. Spreader-stickers can be purchased and any garden supply store. These products help distribute the spray over the entire leaf and help hold it in place.
After applying the glyphosate spray, be patient! You won't see results overnight. It takes time for the chemical to move into the roots and do it's job. You'll have to wait about 10 days before seeing results. In the mean time water the Bermuda grass as you would normally. Remember, the grass should be healthy and actively growing for the glyphosate to work.
A second or even third follow-up spray may be needed to entirely kill the bermuda entirely. If after 10 days following application the lawn has yellowed but is not dead, spray it again. Repeat this process until the lawn has turned brown. In the process of spraying the lawn, keep people and pets off until the spray has dried. The chemical nature of glyphosate is such that it breaks down into harmless constituents when it comes in contact with soil, so it is environmentally friendly.
When your sure the entire bermudagrass lawn has died, mow the lawn and remove the excess clippings. Add them to a compost pile or use them as a mulch around flowers and vegetable plants in the garden. Spade or till in the remaining dead grass plants and work the soil loosen and prepare it for planting of drought-tolerant desert plants.
It's best to wait until cooler weather this fall to do your replacement planting. And when you plant, consider the use of organic mulches for ground cover plantings. Some good organic mulches are ground cypress and cedar bark, forest mulch, or compost. These have benefits over rock mulch in that they keep the soil cooler, do a better job of holding in soil moisture, and improve the soil by adding humus.
Home lawns have a function in providing active play areas for children. But if your kids are grown or if you had a lawn largely for aesthetic appeal, consider replacing it with an attractive desert landscape. You'll be saving yourself money and helping your community save one of it's most precious resources, water!
How to kill bermuda grass
Burmudagrass is a warm season grass well suited to our hot, desert environment. Heat encourages lush, rapid growth, but with it comes the formation of something called thatch. Thatch is the accumulation of dead grass plants and grass roots. It forms as a layer of brown, spongy material between the green grass and the soil. The faster the grass grows, the more thatch is formed. Eventually, this thatch layer becomes a problem. When it gets thick enough, usually ½ inch or more, it begins interfering with the movement of water and bermuda grass fertilizer. Instead of getting to the roots, water is absorbed by the spongy thatch layer. Plant nutrients, in the form of fertilizer, is also tied up and held in the thatch.
Burmudagrass is a matting type grass that spreads by underground stems called rhizomes, and above-ground stems called stolons. When thatch becomes thick, stolons are forced to grow up above the turf, rather than down along the soil surface. When mowed, the protruding stolons are cut and grass can be scalped as the mower sinks into the spongy thatch.
To determine whether your lawn needs to be dethatched, cut a small hole or plug from the lawn with a shovel. Remove it, roots and all, and look for the brown thatch layer. If it's ½ inch or thicker, it's time to have the thatch removed by verticutting or power raking. July is an ideal month to remove thatch. The hot weather encourages a speedy recovery of the lawn. Never dethatch in the cool weather of fall, winter or early spring!
If you have a small lawn area, and want some good exercise, you can remove the thatch by hand raking it. Special lawn rakes are sold at garden and hardware stores especially for thatch removal. These rakes has heavy, U-shaped tines made for pulling out thatch. Cutting the grass as low as possible prior to raking will make the job easier.
If your lawn is larger, you can rent a motorized dethatcher or power rake. These have vertical rotating blades to cut and pull the thatch out. Dethatching or verticutting should be done in several directions to effectively remove the thatch. Landscape contractor are also available to professionally verticutting services.
Because dethatching is somewhat damaging to the turf, it's important to encourage speedy recovery. This is done by fertilizing with 5 pounds of ammonium sulfate (21-0-0) per 1,000 square feet of lawn area. Fertilization and watering will encourage a quick recovery of the lawn.
Although bermuda thrives in heat, it needs frequent watering. During this, the hottest and driest part of the year, the lawn may need to be watered every other day or every third day. With each watering apply between ½ and 3/4 inches of water. To determine how long to let the irrigation system run, set out straight sided cans randomly throughout the lawn. Let the irrigation system run for a designated period of time and then measure the depth of water in each can. Add the individual measurements up and divide by the total number of collection cans. This will give the average amount of water applied. If the amount is less than ½ inch, increase the length of watering. If the amount is greater than 3/4 inch, decrease the length of watering. Then repeat the test to make sure the system has been properly calibrated.
Dry patches of brown grass often develop at this time of year. It's usually the result of poor coverage by the lawn sprinklers. If certain areas of the lawn are getting insufficient water, adjust the sprinklers to wet those areas. This may require cleaning clogged nozzles and their filters, replacing nozzles with ones that have a greater spray radius, or adding more spray heads.
Sometimes dry spots develop when the soil becomes impenetrable to water. If water sheds off and will not soak into the soil, poke holes in the soil with a pitch fork or screw driver. This should improve water penetration. Soapy water can also be used to wet these water shedding patches. Don't use too much soap. One teaspoon of a liquid dish washing detergent in one gallon of water is sufficient. Wet the dry patches once with the soap solution just before your lawn sprinklers come on. One treatment is all that's usually needed.
Finally, to keep your summer lawn looking it's best, mow it frequently. And whether you use a rotary mower or a reel type, make sure the blades are kept sharp.