Research and Reviews: Beef

Special Circular 162-99

The Use of Conservation Reserve Program Land for Grazing Cattle

S. L. Boyles1
The Ohio State University Department of Animal Sciences
boyles.4@osu.edu

M. L. Mohler
Ohio State University Extension

B. W. Stoll
Natural Resources Conservation Service

J. J. Hoorman
Ohio State University Extension

1. For more information, contact at: The Ohio State University, 222F Animal Science Building, 2029 Fyffe Road, Columbus, OH 43210; 614-292-7669; fax: 614-292-1515; e-mail: boyles.4@osu.edu

Abstract

The Conservation Reserve Program (CRP) is a voluntary program under which landowners enter into contracts with the USDA to remove highly erodible and other environmentally sensitive cropland from production. A three-year project was done to evaluate the use of intensive rotational cattle grazing as an alternative for this land when it is removed from crop production. A 40-acre area was divided into 28 cells for grazing. Cattle were moved to a new cell daily. Initial stocking rates were 100, 65, and 40, animals in years 1, 2, and 3, respectively. Yearling cattle (546 +/- 39.5 lbs.) were placed on grass in the spring. Average daily gain was 1.54 +/- 0.066 lbs. per day. The amount of bare ground did not change over time (P < 0.05), even with clover seed application. There was an increase in the population of weeds over time (P = 0.06) with grazing. However, net energy gain (0.27 +/- 0.070 Mcal/lb.) and crude protein (23 +/- 4.7%) did not change over the years (P > 0.05).

The Ohio Environmental Protection Agency (EPA) must notify area residents when water nitrate nitrogen levels are greater than 10 ppm. Only once during the three year period did nitrate nitrogen levels in water run-off exceed the 10-ppm level. This was due to a nitrogen fertilizer application just prior to precipitation. Maintaining forage on what was CRP land and using it for grazing should meet the EPA conservation compliance demands to participate in other USDA programs.

Introduction

There are 346,050 acres of Ohio farmland enrolled in the Conservation Reserve Program (CRP) (Loux et al., 1995). As contracts approach their expiration date, participants are faced with the decision of what to do with CRP acres. Anyone wishing to participate in other USDA programs must meet Conservation Compliance provisions. Agricultural commodities cannot be produced on highly erodible land (HEL) unless soil erosion prevention measures are initiated or installed that maintain soil loss to USDA acceptable standards. Maintaining CRP cover and using it for pasture or hay production should meet the Conservation Compliance demands. A diverse group of people and organizations decided to cooperate on a grazing project (Table 1). The objectives of this project were to monitor the performance and economics of cattle grazed on CRP land and to determine if intensive grazing is compatible with water quality.

Materials and Methods

Land Description

An intensive grazing project was initiated at the Indian Lake Water Shed Project at the farm of Russ and Miriam Forsythe near Belle Center, Ohio. One 40-acre parcel was allocated for the grazing project. Permission was granted from the Consolidated Farm Service Agency (CFSA) to conduct the experiment. The land was seeded to orchardgrass, timothy, and clover eight years ago, when it went into CRP. The soil was a Napponee St. Clair silt/loam with 6-12% slopes which is typical of Logan County, Ohio. The grazing site was mowed once a year during the time the land was in CRP.

Fence Design

The 40-acre pasture ground was divided into four sections. Perimeter fence was high tensile fence (five strands, three electrified). The internal fence dividing sections were one strand of electric fence. In addition, paddock A was completely enclosed in high tensile fence for an arrival area, to acquaint cattle with electric fence. Three sections (A, B, and C) contained 11.3 acres per section and the fourth section (D) comprised 6.1 acres. Each section was subdivided with movable electric tape, so the paddocks were 1.4 acres in size (28 cells). The cattle were moved within the grazing sites each morning.

Water and electric were provided from a nearby barn. Black plastic pipe (0.75 inch, 200 lb. test) was laid along the fence, and a portable water trough was moved to the paddock where calves were currently grazing. Calves had continual access to salt and mineral supplements.

Soil Test, Seeding, and Fertilization

Three soil samples were collected each year and tested for pH, organic matter, phosphorus, potassium, calcium, magnesium, and cation exchange capacity. The samples were collected prior to grazing.

Red clover was frost seeded in March 1995, at a rate of 10 lbs. per acre and again seeded on February 1, 1996, at a rate of 8.75 lbs. per acre on the 40-acre parcel. The grazing site received 7.6 lbs. of red clover per acre and 150 lbs. of pelleted limestone per acre on March 15, 1997.

Nitrogen applications were frequent in 1995 (Table 2) due to an initial stocking rate of two animals per acre. Thirty-two pounds of actual nitrogen was applied per acre on February 1, 1996. No nitrogen was used in 1997.

Four replicated randomly selected sites were evaluated for forage cover and herbage mass in each of the four sections each year. A 3/8 inch steel rod was used to make a square. This device is called a quadrat and the area of the quadrat was two square feet. Forage mass was measured by hand-clipping (Milner and Hughes, 1968). Standing herbage was clipped to about one inch above the soil surface (Bosworth, 1988). Forage and hay samples were dried at 55 degrees C for 48 hours.

Run-off Water Quality

The Ohio Water Quality Standards (Ohio Administrative Code 3745-1-04) specify that all surface water in the state must be free from the following pollutants, as a result of human activity: suspended solids, floating debris, color, odor, toxic substances and nutrients that create nuisance growths of aquatic weeds, and algae. Longitudinally cut plastic barrels were placed in holes in the ground, at natural drainage spots in proximity of the grazing site. Two plastic barrels (Site 1 and Site 2) were placed in the grazing project to collect surface water runoff for nitrate testing, and one barrel (Site 3) was placed adjacent to the project area on CRP land and used as a control. Site 1 was a surface water collection point for sections A and B. Site 2 was surface water collection point for section C. Surface run-off samples were collected if there was a one inch or greater rainfall.

Cattle Description

An area cattle feeder supplied the cattle each year. The cattle were fed on a contract basis. The grazing charge was $0.25 per pound of gain. Steers were grazed in 1995, while heifers were used in 1996 and 1997. The initial stocking rate was 2.5 animals per acre in 1995, 1.625 in 1996, and one animal per acre in 1997. Average initial starting weight was 546 +/- 39.5 lbs. Cattle arrived at the grazing site in 1995, 1996, and 1997, on April 17, April 27, and June 6, respectively. Days on pasture in 1995, 1996, and 1997, were 149, 125, and 122 days, respectively. Cattle were weighed approximately every 30 days. Cattle received a USDA feeder cattle grade (USDA, 1980) at the beginning of the trial and a body condition score (BCS) (Boyles et al., 1992) at the beginning and conclusion of the trial. The body condition score system used was based on a 1 to 9 scale with 1 representing a very thin body condition and 9 representing a very fat body condition.

Cattle had free choice access to mineral supplements containing BovatecTM (Roche, Hoffmann-La Rouche Inc., Nutley, NJ) in 1995 and 1996. In 1997 the mineral contained GainProTM (Hoechst Roussel Vet, Sommerville, NJ). Cattle were implanted with RalgroTM (Mallinckrodt Veterinary, Inc., Mundelein, IL) mid-way through the grazing in 1995. All cattle were implanted with Revalor-GTM (Hoechst Roussel Vet, Sommerville, NJ) mid-way through the 1997 grazing season.

Fecal samples were collected from the rectum on day 0 of the trial and at the end of each weigh period. Samples were kept cool (< 10 degrees C), but not frozen. The cooled fecal samples were delivered in styrofoam containers to a commercial laboratory (Gil Myers, Magnolia, KY) within 24 hours for analysis. The Wisconsin Sugar Centrifugal Method (Bliss 1989) was used to determine fecal worm eggs per gram. Cattle did not receive any parasite control product in 1995. In 1996, cattle were administered Safe-GuardTM (Hoechst Roussel Vet, Sommerville, NJ) supplied in a free-choice mineral for nine days, 23 days, and 55 days after arrival at the grazing site. Safe-GuardTM was administered orally 30 and 60 days after arrival in 1997.

Forage Nutrient Content

Forage samples were collected on weekly intervals after cattle were introduced to the demonstration area. Samples were taken from a paddock just prior to the cattle entering that particular grazing cell. The procedure was to walk diagonally across the field and take small samples and place the collected forage in a sealable plastic bag. The samples were frozen and then sent to The Ohio State University Research Extension Analytical Laboratory in Wooster, OH, for analysis.

Results and Discussion

Stocking Rate

The initial stocking rate was 2.5 animals per acre in 1995, 1.6 in 1996, and one animal per acre in 1997 (Table 3). In 1995 and 1996, cattle had to be removed, or supplemental hay had to be fed to maintain the standing forage reserves. The stocking rate of 2.5 steers per acre in 1995 was selected because it was felt this was the maximum tolerable rate for 450-500 lb. steers on this land area. However, the steers were actually 100 lbs. heavier than anticipated. Twenty steers were removed within approximately one week of the project's onset due to the greater intake of the heavier-than-expected steers. Another 20 steers were eventually removed due to low rainfall during critical time periods.

A wet spring in April and May of 1996 caused trampling damage to occur. The result was reduced forage recovery. The heifers had to be put on an additional 28 acres for a duration of 36 days, in addition, 400 lbs. of hay per head was provided. In August of 1997, the heifers had access to 250 lbs. of hay per head to reduce the stress on the standing forage.

Pasture Cover

The average percent bare ground on the 40-acre grazing site was 26% over the three years of grazing. The amount of bare ground did not decrease (P = 0.07) after three years of grazing (Table 4). In fact, there appeared to be a slight increase in bare ground. Although greater than the protection level (P = 0.06), there appeared to be an increase in weeds from 1995 to 1997. This may have been avoided if initial stocking rates in 1995 and 1996 had not be so high. There was not a change in percent orchardgrass, other grasses, red clover, or other clovers over time (P > 0.05). When all clover varieties were combined, there still was not a change in population representation after three years (P > 0.05).

Average forage height was 4.9 +/- 0.63 inches. Cattle should be removed from a paddock when forage height is two inches, and introduced into a paddock when forages are five inches tall if the pasture contains bluegrass or clover. Cattle should be removed from a paddock when pasture height is three inches, and introduced to a paddock that is 10 inches high if it is a fescue or orchardgrass pasture. Because of the relatively short regrowth, there appeared to be an increase in the amount of clover and a decrease in the amount of orchardgrass. Actual removal height was closer to one inch rather than two inches. Average pounds of dry matter per acre was 1,488 +/- 721.1. Average pounds of dry matter per acre in an inch of forage was 348 +/- 67.1.

There was lower forage production on CRP ground for several reasons. Forage production will not optimize itself without regular forage removal. The grazing area had been mown once a year during its placement in CRP. However, clippings were not removed and thatch accumulated. This accumulated thatch lowers soil temperature and forage production. CRP land is also very deficient in nitrogen which also reduces forage production.

Frame, Muscle Score, and Body Condition

Large and medium frame calves were 33 lbs. heavier (P < 0.05) than small frame calves at the start of grazing. A similar numerical difference in final weight existed. Because of increased variability in final weight compared to initial weight, 12 vs. 23 lbs. standard error, a statistical difference in weight was not detected. Thick muscled cattle had initial and final weights of 75 and 82 lbs. greater (P < 0.05) than medium muscle score calves, respectively. Condition score 5 cattle were 37 pounds heavier than condition score 3 cattle, but the variability in weight did not allow for statistical differences. The difference between condition score 3 and condition score 4 cattle was only four pounds. No differences for average daily gain were detected due to frame, muscle score, or body condition score.

Animal Requirements (Energy and Protein)

Protein levels were higher (P < 0.05) in the spring and late summer than during midsummer (Table 5). However, crude protein levels were consistently above 19% (Tables 5 and 6). Rotational grazing was maintaining the forage in a vegetative state and maintaining high protein levels. The crude protein levels were similar across years.

Net energy values did not change from 1995 to 1997, or from month to month (Tables 5 and 6). The net energy values for gain are adequate for maintaining approximately one pound of body weight gain per day (NRC, 1984 and 1996). Based upon beginning and ending weights, average daily gain was 1.4-1.5 pounds per day. The deworming program and the use of feed additives, and/or implanting the cattle may have further enhanced daily gain. Another contributing factor could be that the excess protein was being converted to energy and resulting in greater body weight gain than predicted.

Animal Requirements (Minerals)

In general, the forage appears to be adequate in most of the minerals required to meet the cattle requirements (Tables 5 and 6). However, supplementation of minerals could be recommended. Sodium levels were not affected by month, but decreased (P < 0.05) over years. Sodium requirements approached 600 parts per million (ppm) and the forage only supplied 18-170 ppm. Therefore a salt (sodium chloride) source should be available free-choice.

Providing a mineral supplement may or may not improve performance, however it is cheap insurance and well worth the cost. Next to sodium, phosphorus is the most important mineral for grazing cattle. The current phosphorus levels in the forage (0.35-0.46) were adequate to borderline in meeting NRC requirements (0.15-0.40%). Although phosphorus forage levels may appear to be numerically adequate, it should not be assumed that all plant phosphorus is available to the animal. Therefore a mineral supplement fed free-choice should contain 5-8% phosphorus for stocker cattle (Bock et al., 1991).

Copper levels ranged from 7-14 ppm. This may be borderline if suggested minimum copper levels are 10 ppm (NRC, 1996). However, the forage copper levels are actually deficient. Copper absorption can be hindered by other minerals such as the presence of high levels of molybdenum (Peterson, 1987). NRC (1996) suggests that the 10 ppm level is adequate if the diet does not exceed 0.25% sulfur and 2.0 ppm molybdenum. The current forage molybdenum levels were, at times, 6.5 times greater than the 2.0 ppm level (13 ppm). It can therefore be assumed that opportunities for copper deficiency could occur if not provided in a mineral supplement. Thornton et al. (1972) observed that forage copper levels of 7-14 ppm were inadequate if forage molybdenum levels were 3-20 ppm.

Ohio is generally considered a selenium deficient region in the United States, and a selenium fortified trace mineral supplement can be cheap insurance. Forage selenium values during June and July were about 0.05 ppm. Suggested minimum levels are 0.10 ppm with a maximum of 2.0 ppm. Selenium levels therefore appeared to be deficient on this CRP site.

Phosphorus, potassium, magnesium, sodium, iron, copper, zinc, selenium, and molybdenum decreased (P < 0.05) over the years (Table 6). While some of these minerals were still adequate after three years, some became deficient. Producers may need to alter their mineral supplementation program over time and certainly consider year-to-year differences.

Grass Tetany Potential (High Potassium)

No symptoms of grass tetany were observed in the cattle. The average magnesium content of the forage in this trial was more than 0.2% (Tables 5 and 6). Minimum needs of sheep and cattle for growth can generally be met by pastures or diets containing 0.10% magnesium, and 0.18-0.20% magnesium is considered necessary for lactating cows (McDowell et al., 1993). A value of K/(Ca+Mg) in excess of 2.2 has been correlated with an increase in the frequency of grass tetany (Kemp and t'Hart, 1957). However, Seekles, as cited by Grunes et al. (1970), questioned the accuracy of the equation K/(Ca +/- Mg) for predicting the incidence of grass tetany. The cattle were given a mineral supplement which contained 10% magnesium.

Soil Test

Soil potassium levels were consistently above 100 lbs./acre (Table 7). Avoiding the use of potassium rich fertilizers should reduce the incidence of grass tetany problems. It is not necessary to include potassium in fertilizers unless the soil test potassium levels are less than 75 ppm potassium (Vitosh et al., 1995). Potassium fertilization was not needed based on the current levels of soil potassium and cation exchange capacity.

Internal Parasite Control

Low worm egg counts throughout the grazing season document that a strategic deworming program can provide full season worm control. As a result, worm infection did not interfere with animal performance. Cattle with such low worm egg counts do not need to be treated with a dewormer when they enter the feedlot. The animal owner could save this expense.

CRP land can initially be considered parasite safe pasture. Because CRP land has not been grazed for years, worms are not present to infect cattle. Cattle owners will benefit from improved weight gains if they maintain parasite control of each grazing season. Pastures used during the 1997 project should have low worm contamination at the start of the 1998 grazing season.

Run-off Water Quality

Ohio EPA must notify area residents when water nitrate nitrogen levels are greater than 10 ppm. Nitrate nitrogen run-off levels for the grazing site averaged 4.4 +/- 4.142 ppm. In only one instance did water run-off levels exceed the Ohio EPA level of 10 ppm (22 ppm). On May 22, 78 pounds of actual nitrogen was applied to one section and 40 pounds of actual nitrogen was applied to an adjacent section of land. A substantial rain (> 1 inch) occurred on May 23, 1995, and water samples were collected on May 24, 1995. The large standard deviation (4.142 ppm) was because one run-off level was 22 ppm. When this value was removed, the average nitrate-nitrogen level was 3.5 +/- 0.99. The average nitrate nitrogen level for the control site was 3.6 +/- 1.51.

Economics

The profit or loss each year was very dependant upon the margin or the difference in purchase price and sale price (Tables 8 and 9). In 1995, the margin was a negative $10.30 per cwt., in 1996 the margin was a positive $9.50 per cwt., and in 1997 it was a negative $8.00 per cwt. The market price at which cattle are bought and sold is very important in determining net returns.

In 1995, although production per head was 175.6 lbs., the gross return was only $44.83 due to a high negative margin. Total direct expenses were $55.84 and overhead expenses were $22.49 per head for a negative return of $33.50 per head. In 1996, even with low cattle prices, a positive margin produced gross returns of $154.50 per head based on 190.23 pounds of gain per head. Total expenses were similar to the previous year, but the net return was $78.87 per head. In 1997, cattle prices recovered and the margin was again negative. Gross returns were $91.86 on the cattle with a net return of $9.03.

To take out the variability in margins, another measure is the cost to break even on contract feeding. In 1995 and 1997, it cost $.45 per lb. to break even on newly converted CRP land to pasture. The lowest cost was $.38 per lb. in 1996. All these break even values could be reduced by $.07 per lb. if hired labor was removed. Hired labor was the major overhead expense.

Summary

Soil test for pH, organic matter, potassium, phosphorus, calcium, and magnesium. Fertilize to apply nitrogen-phosphorus-potassium (N-P-K), and correct soil fertility deficiencies by at least 30 days into the grazing system. It may be necessary to interseed desirable forage species prior to pasturing. For example, red clover can be frost seeded at 10 lbs. per acre in late February to increase the legume content.

Initially, 1.0 head per acre may be all the pasture will support until the new forage species become established. As forage growth and density increase, the stocking rate on this pasture may be increased to 1.5 to 2.0 head per acre. Stocker cattle will become acclimated to hot weather and shade does not have to be provided. In the fall, leave 2-3 inches of growth as pasture cover.

References

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Bock, B. J., S. M. Hannah, F. K. Brazle, L. R. Corah, and G. L. Kuhl. 1991. Stocker cattle management and nutrition. Kansas State University Cooperative Extension Service. C-723.

Bosworth, S. C. 1988. Methods of measuring pasture yields. In: Pasture in the northeast region of the United States. Northeast Regional Agricultural Engineering Service. pp. 105-113.

Boyles, S., T. Flakoll, and K. Ringwall. 1992. Cow nutrition and body condition. North Dakota State University, NDSU Extension Service. AS-1026.

Grunes, D. L., P. R. Stout, and J. R. Bronell. 1970. Grass tetany of ruminants. Advan. Agron. 22:331-374.

Kemp, A. and M. L. t'Hart. 1957. Grass tetany in grazing milking cows. Neth. J. Agric. Sci. 5:4.

Loux, M. M., R. M. Sulc, P. Thomison, J. E. Beuerlein, and J. Johnson. 1995. Converting CRP land to cropland or pasture/hayland: agronomic and weed control considerations. Ohio State University Extension. Extension Fact Sheet. AGF-024.

McDowell, L. R., J. H. Conrad, and F. G. Hembry. 1993. Minerals for grazing ruminants in tropical regions. 2nd Ed. Animal Science Dept., University of Florida.

Milner, C. and R. E. Hughes. 1968. Methods of the measurement of primary production of grassland. Blackwell Sci. Publ., Oxford, England.

NRC. 1984. Nutrient requirements of beef cattle. 6th Ed. National Academy Press. Washington, D. C.

NRC. 1996. Nutrient requirements of beef cattle. 7th Ed. National Academy Press. Washington, D. C.

Peterson, M. K. 1987. Considerations in trace mineral supplementation. Proceedings. The Range Beef Cow Symposium X. p. 121.

Thornton, I., G. F. Kershaw, and M. K. Davies. 1972. An investigation into copper deficiency in cattle in the Southern Pennines. 2. Response to copper supplementation. J. Agric. Sci. Camb. 78:165.

U.S. Department of Agriculture. 1980. U.S. standards for feeder cattle. Agriculture Marketing Service. AMS-586.

Vitosh, M. L., J. W. Johnson, and D. B. Mengel. 1995. Tri-state fertilizer recommendations for corn, soybeans, wheat, and alfalfa. Michigan State University Extension. E-2567.