In addition to agricultural production, it is an important species in erosion control and turfgrass applications because it is fairly easy to establish, covers rapidly and tolerates traffic well.

Funderburg eddie
Soils and Crops Consultant / The Samuel Roberts Noble Foundation

Bermudagrass is fast-growing, hardy and tolerant of high levels of salt, a wide variety of soil and environmental conditions, heavy grazing and many herbicides. It will withstand several weeks of flooding, especially if the water is moving.

However, bermudagrass does not tolerate cold winters or shade of more than 30 percent during the growing season. It requires hot weather and abundant soil moisture for best growth. Average daily temperatures above 75ºF are required for substantial growth.

Temperatures of 100ºF result in maximum growth rates if soil moisture is not limiting. Bermudagrass enters dormancy when temperatures are less than 32ºF.

Bermudagrass must be properly managed to achieve optimum forage utilization. Proper management covers many subjects, but this article will cover weed control and fertilization.

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Control what you don’t want

Since bermudagrass is not shade-tolerant, it is necessary to control weeds. For our definition, a weed is a plant in the field you do not want. You may not want it because it suppresses bermudagrass growth, reduces forage quality or is toxic to animals. The first step in weed control is scouting the fields to determine the species and numbers of weeds present.

If there are enough weeds to justify treatment, decide how you wish to control the weeds. In general, possible control measures are biological, mechanical and chemical.

Biological control refers to any treatment that uses living organisms to control weeds, but usually it involves using animals such as goats. This is great if you have the resources and management to make it work, but it is not practical for the vast majority of forage producers.

Mechanical control refers to treatments that physically cut down weeds. The two main mechanical measures are mowing and using implements like shovels or hoes to remove individual plants. Individual plant removal with hoes or shovels works well if you have a few undesirable plants that can be easily identified and removed.

For example, if there are a few toxic plants in a field, they can be cut down and removed without treating the entire area. Obviously, this method does not work well when large numbers of undesirable plants are present.

Mowing is often used to control weeds, but has some drawbacks. One, it cuts down desirable forage along with weeds. Most pasture weeds re-grow after mowing, so it is only a temporary remedy. It is usually more expensive and time-consuming than spraying herbicides.

Mowing is usually practiced by producers who do not want to use herbicides or in areas where herbicide use is impractical. Examples of these areas include parts of fields that closely border sensitive plants that may be damaged by herbicide drift.

Herbicides are commonly used for weed control in forage crops. Properly used, they are effective against targeted weeds and do not damage forage grasses. It is vital to select the correct herbicide and apply at the correct growth stage of the weed with the correct rate.

The proper herbicide is determined by scouting the fields to determine your weed spectrum. The rate and proper growth stage to treat the weed are determined by reading herbicide labels. Always read the label and follow its instructions when applying herbicides. Always calibrate your sprayer so you apply the proper rate. Take precautions to limit off-site drift when applying herbicides.

Planning your fertilization

Bermudagrass responds well to fertilizer. Stocking rates can be manipulated on a field by varying the fertilizer rate. The amount of fertilizer to use is determined by the variety of bermudagrass, precipitation (or irrigation capacity) in your area and the amount of forage you need.

Do not apply fertilizer unless you have results from a recent soil test (within the last three to five years). If the soil test results call for lime, phosphorus or potassium, be sure to correct these deficiencies before you use nitrogen. Many producers only use nitrogen on forage crops.

This is correct if the other nutrients are at optimum levels, but nitrogen is used very inefficiently if soil pH, phosphorus or potassium levels are low. For example, phosphorus is commonly deficient in soils in southern Oklahoma.

Research shows that bermudagrass does not respond well to nitrogen fertilizer if soil phosphorus is deficient and is not applied according to soil test results. Therefore, we do not recommend fertilizing at all if a producer is not willing to apply all the nutrients recommended on a soil test report.

Bermudagrass varieties do not respond to nitrogen fertilizer in the same way. Some varieties do not have the yield potential to utilize high rates of nitrogen. Fertilizing more does not make the forage grow more. For this reason, we usually recommend no more than 50 pounds of nitrogen per acre on these lower-yielding varieties.

Hybrid varieties, like Coastal, Midland 99 and Tifton 85, can utilize much higher rates of nitrogen and be fertilized much more heavily. It is important to know the variety of bermudagrass in your field to develop a proper fertilization program.

Precipitation should also be taken into consideration when developing a fertilizer program. Areas with higher rainfall rates or fields with irrigation can be fertilized more heavily than areas that receive lower rainfall rates.

Research has shown that applying 1 pound of nitrogen will result in an additional 10 to 40 pounds of dry matter bermudagrass. The variation is due to variety and precipitation. Use these figures to manage your fertilizer program for the amount of forage needed.

Many people think nitrogen rate is the primary factor influencing crude protein in bermudagrass. However, the maturity of the plant affects quality much more than nitrogen rate. Research at Louisiana State University showed that bermudagrass contains about 20 percent crude protein at 14 days of growth but decreases to 6.5 percent crude protein at 56 days of growth. Crude protein was 11.3 percent at 28 days of growth.

Research done at the Noble Foundation showed that crude protein increased 1 to 2 percent, and total digestible nutrients increased 0.5 to 0.9 percent, per 100 pounds actual N per acre applied, depending on variety. So while nitrogen rate has an effect on bermudagrass quality, it is far outweighed by harvesting or grazing at the correct growth stage.

There are many other factors to consider in managing bermudagrass, but proper weed control and fertilization are vital steps to improving forage quality. Best wishes in your forage program.  end mark

Eddie Funderburg