THE UNIVERSITY OF TENNESSEE AGRICULTURAL EXTENSION SERVICE SP 435-A

Renovation- Plant Clovers in Grass Pastures Gary Bates, Assistant Professor, Plant and Soil Science

goal of cattle producers should pounds of nitrogen per acre (Table 1). be to provide the nutrients A their cattle require as eco- (2) Improved animal performance nomically as possible. Allowing the Research has shown that clovers cattle to acquire their own feed through improve animal gains and conception grazing is the most efficient way to rates (Table 2). High quality feed is provide these nutrients. The majority of important for a calf to gain well and cattle in Tennessee graze tall fescue or for a cow to rebreed after calving. orchardgrass pastures. While these pas- Clovers are more digestible and contain tures provide good quality forage over a more nutrients than grasses. Their pres- long portion of the year, they can be ence in a pasture improves the palat- improved. One of the best and easiest ability of the forage, which will in- ways for improvement is to add legumes crease the amount and quality of the such as red or white clover and annual forage the animal consumes. Research has lespedeza to these pastures. also shown that including clovers in an endophyte-infected tall fescue pasture Benefits of clovers helps decrease fescue toxicosis (see Adding clovers to pastures or hay Table 1. Yield and composition of fields can produce benefits in four tall fescue pastures with and without legumes. ways: (1) Increased yield Yield Forage species (2) Improved animal performance (lb DM/acre) (3) Nitrogen fixation (4) More summer production tall fescue + 60 lbs N/acre 2975

(1) Increased yield tall fescue + white clover 3155 Research in Tennessee has shown that tall fescue overseeded with white tall fescue + white clover + clover, or a combination of white clo- red clover + annual lespedeza 3860 ver, red clover and annual lespedeza, will produce more forage than a pure Adapted from: H. Fribourg. 1978. tall fescue pasture fertilized with 60 Tennessee Farm and Home Science. 107:16.

Foraging Ahead for 1a Greener Tomorrow SP439-A, Tall fescue: endophyte-infected nitrogen per acre. If at least 30 per- vs. endophyte-free). The result is an cent of the ground area in a pasture is increase in weaning weights, milk pro- covered by clover, there will be no need duction and conception rates. to apply any nitrogen in the spring. If nitrogen costs 25 cents per pound, this (3) Nitrogen fixation would be a savings of 15 dollars per Another characteristic that makes acre each year. legumes a desirable component of a pas- ture is their ability to provide nitro- (4) More summer growth gen. Rhizobium is a group of bacteria The majority of the growth from which enter the roots of legumes and cool-season grasses such as tall fescue form nodules, or knots (Fig. 1). The and orchardgrass occurs during the bacteria inside these nodules take ni- spring and fall. During the summer, high trogen from the atmosphere and put it temperatures and drought cause these into a form that the plant can use. Not grasses to slow or stop production. only is the nitrogen available to the Several legumes such as red clover and legume, but the surrounding grass plants annual lespedeza can extend the grazing can use a portion of this nitrogen. The season and provide high quality pasture ability of legumes to “fix” nitrogen is that is otherwise unavailable during actually the result of this mutualistic this summer forage slump with pure tall relationship (beneficial to both) be- fescue or orchardgrass pastures. tween the legume and the bacteria. The bacteria get energy from the legume, Steps for renovation: while the legume gets nitrogen from the bacteria. (1) Remove excess pasture growth The amount of nitrogen fixed can differ according to the legume used. The prior to renovation. amount can range from approximately 50 This is best done by grazing down pounds of nitrogen per acre each year to a for annual legumes such as crimson clo- 1-inch stubble in late fall or winter. ver and annual lespedeza, to more than Removing the excess forage will help 150 pounds per acre each year for al- ensure the legume seeds will come in falfa. Research has repeatedly shown contact with the soil. that including a clover in a grass pas- ture can replace about 60 pounds of (2) Fertilize and lime according to soil test. Legumes require a higher soil pH Table 2. Effect of white clover on animal performance. and fertility level than do grasses. Fertilizing by soil test 1 Performance Tall fescue Tall fescue/ Improvement will ensure Measurement white clover (%) that legume establishment cows in study 38 38 ---- will not be limited by conception rate (%) 71 92 30 low pH, pot- ash or phos- calf daily gain (lbs) 1.28 1.82 42 phate levels. DO NOT APPLY weaning weight (lbs) 351 426 21 NITROGEN. Nitrogen will pounds weaned/cow 249 395 59 stimulate grass growth, 1 fertilized with 150 lbs of nitrogen per acre. Adapted from: Lechtenberg and co-workers.1975. Indiana Beef-Forage Research. p. 3.

Foraging Ahead for a2 Greener Tomorrow 2 THE UNIVERSITY OF TENNESSEE AGRICULTURAL EXTENSION SERVICE thereby increasing the competition with broadcast the seed after disking. the legume seedlings. Competition may also be decreased chemically. The objective is to kill or (3) Select the proper legumes. suppress 50 percent of the grass sod The major legumes used in grass with the herbicide. Spraying in alter- hay fields and pastures in Tennessee are nating bands with a herbicide labeled white clover, red clover and annual for pasture renovation, such as lespedeza. White clover is the most Gramoxone Extra®, has been successful. tolerant of grazing. Red clover provides Spraying alternating bands can be accom- greater forage yields and will be pro- plished by either turning nozzles so ductive later into the summer than white areas between nozzles are left clover. Annual lespedeza will provide unsprayed, or by lowering the boom so more production during mid to late sum- the spray patterns do not overlap but mer, especially on droughty hillsides. leave a 5- to 10-inch area unsprayed. See Table 3 for recommended seeding For example, if a boom-type sprayer has rates. nozzles spaced 20 inches apart, the boom Be sure to plant certified seed of could be lowered to the point where only a recommended variety. Using certified 10-inch bands are sprayed by each seed is the only way to be sure of what nozzle. If the boom cannot be lowered, you are planting. Check with your local the nozzle tips can be turned to produce Extension office for recommended variet- alternating 10-inch sprayed and ies. Also be sure to inoculate the seed unsprayed bands. Use Gramoxone Extra at with the proper Rhizobium bacteria, or the rate of 2 pints per sprayed acre. purchase pre-inoculated seed. This will Since only 50 percent of the ground area ensure that the bacteria needed for in an acre will be sprayed, the amount nitrogen fixation are present during of Gramoxone Extra needed to renovate 1 seed germination and seedling develop- acre will be 1 pint. Use a non-ionic ment. surfactant at 2 pints per 100 gallons of spray mix, and apply 15 to 20 gallons of water per acre (30 to 40 gallons per (4) Plant the seed February 20 to sprayed acre). The seed can be drilled March 31, making sure the seed makes or broadcast after spraying. good contact with the soil. The seed is dependent upon mois- Advantages of using disk renovation: ture from the soil for germination and 1. Thin stands need little disking. establishment. Good seed-to-soil contact 2. Most farmers own a disk and can is essential for obtaining a strong use their own equipment. legume stand. There are several methods 3. Disking can be done in the winter of planting. A simple but effective when the tall fescue is dormant,while method is to broadcast the seed during herbicides must be sprayed when the the last two weeks of February. As the grass is green and actively growing. soil freezes and thaws, the seed will be worked into the ground. Allowing cattle Advantages of herbicide renovation: to trample the seeds into the ground 1. Thick sods can be renovated will help ensure the seeds are covered. without disturbing the soil,keeping the If the grass sod is thick, it may surface smooth. Rocks remain undis- be necessary to use a disk to open areas turbed. for the seeds to contact the soil and 2. Wet soils can be sprayed be become established. Use the disk to fore they are dry enough to disk. disturb about 50 percent of the sod. Not 3. Grass plants in the unsprayed only will this improve seed-to-soil areas will produce more forage contact, but will also help reduce the than the plants that have been competition from grasses. Drill or disked.

Foraging Ahead for 3a Greener Tomorrow 3 THE UNIVERSITY OF TENNESSEE AGRICULTURAL EXTENSION SERVICE Table 3. Recommended seeding rates for graze them down to 2 to 3 inches or mow legumes used in renovation. them for hay. This will prevent the spring flush of growth from shading the legume(s) used seeding rate clovers. A good rotational grazing plan (lb/acre) will help maintain the clovers. If an- nual lespedeza is used, graze the pas- white clover 2 tures hard in April and May. This will allow light to penetrate down into the red clover 8 plant canopy where the lespedeza seed- lings are. annual lespedeza 25-35 Summary Legumes are a valuable component white clover + 2 of a pasture or hay field because they red clover + 4 result in improved animal performance annual lespedeza 8 and a decreased need for nitrogen. Ei- ther of these benefits alone is enough to make the legumes profitable. Having both makes legumes a component of the Managing renovated fields pasture that we should focus on con- Once the legumes have been estab- stantly. The steps listed in this publi- lished in the pasture, management will cation should help establish and main- be one of the key factors influencing tain the legumes in our fields. the maintenance of the legume component of the field. The following steps will Precautionary Statement help keep the clovers in the pasture: To protect people and the environ- ment, pesticides should be used safely. (1). Keep fertility levels high. This is everyone’s responsibility, espe- cially the user. Read and follow label Follow an annual fertility program directions carefully before you buy, mix, based on soil test recommendations. Take apply, store, or dispose of a pesticide. a soil sample at least every third year According to laws regulating pesticides, to be sure enough fertilizer and lime they must be used only as directed by the are being used. DO NOT APPLY NITROGEN. label. Nitrogen will not kill legumes, but it Pesticides recommended in this pub- stimulates grass growth, which will lication were registered for the prescribed increase the competition with the legume uses when printed. Pesticide registrations are continuously being reviewed. Should and the likelihood of legume loss due to registration of a recommended pesticide shading. be canceled, it would no longer be recom- (2) Mow or graze pastures to favor mended by The University of Tennessee. the legume. Use of trade or brand names in this Do not allow the grass in the publication is for clarity and informa- tion; it does not imply approval of the field to grow tall and get too mature. product to the exclusion of others which Not only will this result in poor qual- may be of similar, suitable composition, ity pasture or hay, but will result in nor does it guarantee or warrant the stan- the shading of the legumes. If the pas- dard of the product. tures reach 6 to 8 inches tall, either SP435A-5M-6/95 E12-2015-00-297-95

A State Partner in the Cooperative Extension System The Agricultural Extension Service offers its programs to all eligible persons regardless of race, color, age, national origin, sex or disability and is an Equal Opportunity Employer. COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS The University of Tennessee Institute of Agriculture, U.S. Department of Agriculture, and county governments cooperating in furtherance of Acts of May 8 and June 30, 1914. Agricultural Extension Service Billy G. Hicks, Dean Foraging Ahead for a4 Greener Tomorrow