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Cooperative Extension Service |
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Agricultural
Experiment Station |
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Aquaculture
Dale Bumpers College
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Forage and Pasture
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Endophyte Infected (E+) |
Low Endophyte or Endophyte-Free (E-) |
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Kentucky 31 |
Kentucky 31 Uninfected (E-) |
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Forager |
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A. U. Triumph |
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Fawn |
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Martin |
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Cajun |
Seeding Dates, Rates and Procedures
Fescue should be planted at rates of 10 to 15 pounds of good seed per acre between September 1 and November 1 or between March 1 and April 15. Use higher seeding rates with late seeding dates, poorer seedbed preparation, poor growing conditions, and broadcast seedings. Use the lower rates when other forage species are included in the mixture, when ideal growing conditions prevail at planting time, and when the seed are drilled on a good firm seedbed.
If a new field of fescue is to be planted where fescue was not the previous crop and the seedbed is to be plowed, the following steps should be followed:
1. Test the soil by following a system prescribed by the local Extension office. Sampling should be done well in advance of the intended date of seeding so that sufficient time is allowed to receive results and recommendations prior to seedbed preparation.
2. Apply lime and fertilizer as prescribed by the soil testing laboratory. Apply lime and fertilizer prior to seedbed preparation to allow best placement of these soil amendments.
3. Plow the ground several weeks ahead of planting to incorporate the lime and fertilizer into the root zone. This is a critical step since the field may not be plowed again for as long as a stand lasts. Use good judgment in contour plowing and leaving undisturbed waterways in the draws if erosion is likely. Less erosion is likely with fall than with spring plowing.
4. Disk and cultipack ahead of seeding if possible. Ideal depth of seed placement is ¼ inch.
Managing New Plantings
When young fescue plants emerge and begin to grow vigorously, a 50-pound-per-acre application of nitrogen fertilizer will stimulate their growth. Nitrogen, however, will discriminate against young legumes in the stand and may encourage grass growth to the point that clover is shaded out.
Spring plantings of pure fescue may be grazed back to a 3-inch stubble height when young plants accumulate an 8-inch growth. However, it is generally best that fall-seeded fescue remain ungrazed until the following spring. Small seedlings are easily damaged by trampling on muddy fields and by being pulled from the ground by grazing animals. Careful observation of the stand during the first grazing period is essential.
If grassy weeds appear to be a problem in young stands, then grazing may be necessary before the fescue reaches 8 inches tall. Broadleaf weeds may be controlled by grazing or with herbicide applications while weeds are small. Contact the county Extension office for recommended herbicides and application procedures.
Thickening up Partially Killed Stands
Sometimes old stands of fescue are partially killed by overgrazing or by severe summer droughts. It is difficult to “thicken up" a damaged forage stand. Therefore, fewer problems are encountered if the field is completely replanted. However, there are other alternatives. If 50 percent or less of the fescue is dead, the stand is ideally suited for including legumes in the field. Renovating fescue pastures with legumes is a very viable option.
If more than 75 percent of the fescue stand is dead, it is probably best to sacrifice the remaining 25 percent in order to prepare a new seedbed for reseeding. If 25 to 50 percent of the old stand remains, the decision is whether to “thicken up" the old stand or to plow it up and replant.
If close to 50 percent of the fescue is alive, it will probably be worthwhile to save the remaining part of the stand and plant a mixture of fescue and clover. One method of doing this would be to apply fertilizer (consult your soil test for rates), lightly disk, broadcast or drill the seed by early March or in September and then drag, harrow, or cultipack the field to cover the seed lightly. An alternative system would be to plant the seed with a drill on undisturbed soil after first spraying the field with a herbicide to control weeds. This latter system has its greatest merit on fields that are likely to erode if the soil is disturbed with a tillage implement.
Legumes
White clover is probably the most commonly used legume with fescue in Arkansas. As long as fescue or some other grass comprises 50 percent or more of the stand, the likelihood of bloat is not great with white clover or other legumes. White clovers are shallow-rooted perennials that grow well on both poorly drained and better drained soils. A 2-pound seeding rate per acre provides a good stand. The seed of all clovers and other legumes should be carefully inoculated before planting so that the full benefit of their nitrogen-fixing ability is realized.
Other legumes are less commonly grown with fescue. Crimson clover (12 pounds per acre), arrowleaf clover (8 pounds per acre), subterranean clover (10 pounds per acre), hop clover (1 pound per acre), or red clover (10 pounds per acre) are occasionally used. Alfalfa (12 pounds per acre) will grow with tall fescue but has rarely been used in Arkansas. Lespedeza, which is seeded at a rate of 15 to 25 pounds per acre, works well with fescue. The two main advantages of lespedeza are 1) it produces quality forage at a time of the year when pastures are typically low in forage availability and quality (July to September) and 2) it will grow well on acid soils (down to pH values as low as 5.4) unlike all other legumes which require a pH of 6.2 or higher.
To incorporate legumes into existing stands of fescue, it is necessary to accomplish four management practices. These practices are:
(1) open the fescue stand by killing or greatly retarding at least 50 percent of the existing sod (assuming that a full stand already exists) – this can be done with a disk or herbicide after the field has been closely grazed;
(2) planting good seed as early as possible in the planting season (for white clover this is September 15-November 1 for south Arkansas, September 1-October 15 for north Arkansas, and February 15-April 1 for all areas);
(3) fertilizing and liming to favor the legumes; and (4) rotationally grazing new stands to favor the legume.
Proper Use of Fescue
Grazing
There is an old forage adage, “Produce and Utilize." A grazing management system, regardless of whether it be continuous or some form of controlled grazing should be selected to match each producer’s ability to profitably manage both forages and livestock. Controlled grazing, rotational grazing, intensive grazing, cell grazing and controlled rotational grazing are terms that have been used to identify planned grazing management practices. These terms are used to differentiate planned grazing management from continuous grazing.
The most economical method of using forages is with a grazing animal. Ideally, we would like to be able to provide 365 days of available adequate-quality forage. While this is not presently a practical practice, many livestock producers have been able to reduce their days of hay feeding down to 30 to 60 days per year. This has been accomplished primarily through changes in their grazing management program. Grazing management can either affect beneficially or detrimentally forage availability, quality and persistence.
Controlled grazing allows the producer to better use the supply of forage when it is the most nutritious and abundant. It also allows a limited forage supply to be stretched when growth slows in hot or cold weather, thereby reducing the need for hay. Pastures properly grazed and rested grow longer in the early stages of drought and revive quicker after rain. The suggested height to begin grazing fescue for maximum yields, quality and persistence is when fescue plants reach 4 to 6 inches in the fall and again in the spring. It is recommended that livestock be moved to another pasture when plants are grazed down to an average height of 2 inches. Controlled grazing allows plants to rest and this helps avoid the severe shock that some continuous grazed fescue pastures experience. Forage use efficiency (which translates into more grass for the cow herd) has been shown to increase 10 to 35 percent in grazing research trials. This can mean that more cattle per farm can be carried or that more hay is available for use on the farm or that hay for use as a cash crop is available.
One of the challenges in managing fescue in a grazing system is to minimize seed head formation in the spring. Fescue like most other cool-season perennial forage grasses produces seed heads one time per year. This occurs during a two-week period in late spring after the plant has been triggered by the appropriate day length. When this occurs, vegetative growth slows and digestibility of plants decreases. Start grazing early in spring to prevent the grasses from getting too much of a head start. Move the animals through pastures quickly as seed heads begin to emerge.
Early in the year, producers may want to open all the gates and allow the cattle to graze all pastures until growth begins to accumulate. After this the gates can be closed and the rotational grazing begun. Mowing excess forage accumulation (for hay) or grazing when plants reach the boot to early head stage helps to maintain pastures in a more leafy vegetative growth state.
If pastures are grazed heavily enough in spring to eliminate at least 50 percent of the seed heads, clipping is not likely warranted. Animals tend to eat these “escape" seed heads the next time they graze that pasture.
Grazing fescue pastures in this manner will be helpful in providing forage that is readily available and of adequate quality. This method of spring fescue forage use is helpful in lowering endophyte problems on pastures that predominately contain E+ fescue varieties such as Kentucky 31.
Haying
Sometimes, particularly in the spring, cattle numbers may not be available to generate adequate "grazing pressure." During these times, fescue tends to “get ahead" of the cattle. As this happens, quality is generally deteriorating. The second option for fescue use is hay production.
Fescue can make a very nutritious hay if harvested in the boot to early head stage for the first cut and afterwards at 4 to 6 week intervals. Fescue hay harvested at these stages of plant development from a number of Arkansas farms were analyzed and found to contain an average of 16.8 percent crude protein and 63.5 percent TDN.
It is important to remember that the single most important producer-controlled factor affecting hay quality is stage of maturity at harvest. How tall the fescue is at cutting affects yield.
Stockpiling Fescue
Tall fescue works very well as fall stockpiled forage for winter grazing. This concept of winter feeding has been used by livestock producers for more than 30 years, but it has also been overlooked as one of the most economical ways of wintering livestock. It is certainly cheaper than feeding hay and generally cheaper than winter annuals. Stockpiled fescue lends itself well to a cow-calf operation whereas stocker operations typically rely on winter annuals.
Tall fescue has a major advantage over other cool-season grasses in its ability for late summer and fall vegetative growth to be stockpiled for deferred grazing in late fall and winter. Stockpiled growth is characterized by accumulation of leaves, which under favorable conditions remain relatively green with high carbohydrate concentrations into early winter. Stockpiled tall fescue exhibits less loss of forage digestibility and crude protein concentration than in other stockpiled cool-season grasses.
Timing of the initiation of the stockpile period has been shown to greatly influence quality of forage available for winter grazing. Tall fescue accumulated from mid-June to early July tends to be much lower in quality than does forage accumulated from early to mid-August. Early August grazing or clipping is very important for obtaining a high quality winter stockpile. It is estimated that maximum per acre yield for stockpiling is achieved with about 75 days of growth in early fall. To determine when to begin stockpiling pasture, estimate your last day of active growth and back up 75 days. For example, if November 25 is the end of your growing season for fescue, target September 10 to begin stockpiling.
The rate of quality deterioration during the winter months is highly dependent on how the standing forage is used. When cattle are allowed access to the entire stockpiled fescue pasture, quality declines much more rapidly than if cattle graze down small paddocks one after another. The physical activity of cattle stirring the forage as they graze opens it up to weather. This weather damage accelerates the deterioration of both forage quality and dry matter losses. Therefore, using deferred or stockpiled fescue in a controlled grazing system (strip grazing using portable electric fencing or use of multiple-paddocks) will lengthen the availability of quality forage compared to continuous grazing of the entire stockpiled fescue acreage.
Applying 40 to 60 pounds of nitrogen per acre (115 to 175 pounds ammonium nitrate or 90 to 135 pounds urea) at the beginning of the stockpiling period is usually a cost-effective practice. If soil moisture is favorable, use the higher rate. In pastures where at least 30 to 40 percent of the annual forage production comes from a legume, applying nitrogen probably won’t pay.
One of our goals in a beef cow-calf program is to provide as much of the animals’ nutrient requirements with forages as possible. The more days livestock can spend grazing and the fewer days they are fed hay and other supplements, generally, the lower the cost of production tends to be. Using stockpiled fescue is one management opportunity that is a proven economical tool.
Fescue Animal Disorders
Three major types of animal disorders associated with consuming endophyte infected fescue forage or seed are fescue foot, bovine fat necrosis, and fescue toxicosis (formerly referred to as “summer syndrome"). Fescue foot is characterized by gangrenous and necrotic tissue at the animal’s extremities, namely the tail, ears, and feet, with severe cases showing loss of the tail or hoof. This disorder usually occurs during the winter, especially when grazing stockpiled or N-fertilized tall fescue.
Fat necrosis is the accumulation of dense, necrotic fat deposits in the abdominal cavity of cattle, and occurs most likely in virtually pure tall fescue stands amended with high rates of N fertilizer, either from commercial or poultry litter sources. Acute cases can cause death in cattle by intestinal strangulation. Evidence suggests that fat necrosis is associated with consumption of endophyte-infected fescue; however, direct cause and effect have not been established.
Fescue toxicosis describes the general conditions of unthrifty appearance and poor animal performance, exhibited especially during high temperature periods. This disorder is responsible for the major economic losses to the USA beef industry caused by consumption of endophyte-infected tall fescue. The complex of symptoms includes poor weight gain and milk production, rough hair coat, excess salivation, elevated body temperature, depressed serum prolactin levels and standing in shade and water.
The economic impact is greatest in the cow-calf industry because of the predominance of tall fescue use in that sector. In 1993, researchers surveyed 21 eastern states and summarized that fescue toxicosis reduced calf-weaning percentages from a potential of greater than 90 percent to 74 percent, for a loss of $354 million. Weaning weights were estimated to be reduced by 50 pounds for a further loss of $255 million annually.
Minimizing Fescue Animal Disorders
Which tall fescue is best for grazing – infected or endophyte-free tall fescue? The data present both sides, defining the “good news, bad news" about each type of tall fescue. If we continue grazing infected tall fescue, we can experience as much as a 50 percent reduction in animal gains; however, our pastures will probably persist. On the other hand, if we switch to endophyte-free tall fescue, we will experience excellent animal gains but may lose our stands to drought, overgrazing, insects or diseases. In Arkansas, the bottom line is to reduce our reliance on endophyte-infected tall fescue as a year-round grass. Below are some management options.
1. Release bermudagrass.
Spray glyphosate (Roundup™) on fescue in March when it is actively growing but before the bermudagrass comes out of dormancy. This removes competition from fescue and allows the bermuda to spread out and fill in. Spraying may have to be repeated the following March to catch escaped fescue plants.
2. Rotate to other pastures.
For several reasons, moving cattle off of fescue during the hot summer months greatly increases animal gains. First, fescue is not productive during the summer months, so moving cattle to a summer pasture simply gives them something to graze. Second, high temperatures can intensify the toxic effect of infected fescue, so moving them to a non-toxic pasture usually eliminates summer slump. Research by Garner in Missouri suggests that 88°F may be a threshold for significantly decreased gain. After moving, keep cattle off infected tall fescue for the entire summer. Researchers in other states report a residual effect of toxicity, suggesting that rotating off of tall fescue for a mere one to two weeks does not greatly reduce summer slump. Alternative warm-season grasses to bermudagrass include bahiagrass, dallisgrass, plains bluestem and eastern gamagrass for central and south Arkansas, and dallisgrass, eastern gamagrass and caucasian bluestem for north Arkansas.
3. Dilute with other forages.
Infected fescue can be diluted with legumes. In Arkansas, common grazing legumes for interseeding are red clover, white clover, annual lespedeza and grazing-type alfalfa. Each of these legumes differs in its persistence, but all can be maintained by proper management. Annual lespedeza must be allowed to reseed in late August and early September. Red clover may require occasional reseeding if they are not allowed to reseed naturally every two years. Legumes should be inoculated, and mixtures should not receive much nitrogen (0 to 30 pounds per acre) unless stocking rate is high or hay is cut.
4. Supplement.
Supplementing with corn or other feeds also reduces the toxic effects of the endophyte on cattle. Although feeding corn at a rate of 1 percent of body weight can be effective, it may interfere with efficient forage fiber digestion. For this reason, feeding corn at a rate of 0.5 percent of body weight or less offers an economic compromise – it allows efficient digestion of forage fiber, lowers feed costs and reduces the effects of toxicity. An alternate supplement is corn gluten feed, and it can be fed at a higher rate without interfering with fiber digestion.
5. Fertilize properly.
High nitrogen rates increase toxicity. Nitrogen increases ergovaline, the toxin produced by the endophyte, and probably contributes to the nutrition of the endophyte. High rates of nitrogen can also decrease the legume component in a mixed sward. For these reasons, fertilizing for the legume is the proper approach to managing infected tall fescue. Do not apply more than 1 ton per acre per year of broiler litter to endophyte-infected fescue.
6. Graze properly.
Infected fescue should be closely grazed. When it is allowed to develop seed heads, it becomes more toxic. This occurs because seed heads contain much more ergovaline than do other plant parts. In addition, mature infected fescue contains less protein and more fiber than leafy, immature fescue. Be aware that the risk of cattle having fescue foot is high on infected fescue pasture that has been stockpiled for several years and fertilized with nitrogen.
7. Replace with endophyte-free tall fescue.
This should be attempted only on the land with the best water-holding capacity and only after enough warm-season grass acreage is established. To replace infected tall fescue, follow the “spray-smother-spray" recipe. Replacement involves spraying infected Kentucky 31 with an effective herbicide, seeding a smother crop and replanting endophyte-free tall fescue or a similar forage. For spring seedings, the preceding smother crop should be a summer annual, such as sudangrass. In the process of renovation, exercise caution. If the land is drought-susceptible or heavily grazed, total renovation is not wise. Instead, small renovations (10 to 20 acres) are prudent. If the land is productive, larger renovations are appropriate. In three independent studies, replacement to endophyte-free fescue has been shown to be cost-effective.
8. Ammoniate hay.
Ammoniation of hay is treating hay with anhydrous ammonia. There are excellent reasons to ammoniate low quality hay. First, ammonia breaks cell wall linkages and increases digestibility. Second, ammoniation requires hay to be covered; therefore, it indirectly provides an excellent storage facility for hay. In the case of toxic feed, there is a third reason to ammoniate – ammonia can reduce the effect of endophyte toxins. (In grain crops, ammonia has the same effect on alfatoxins.) Ammoniation of toxic fescue can increase daily gains by at least 50 percent, an increase higher than expected by merely improving digestibility.
9. Beware of magic cures.
According to current research, addition of minerals, hormones and other animal treatments do not significantly improve daily gains if the animals are already consuming a balanced diet. At present, there are no proven animal treatments available.
For more information about fescue, please contact your county Extension office or refer to one of our publications.
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University of Arkansas • Division of Agriculture |
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