Gallagher Expert Series: The Economic Benefits of Rotational Grazing

Effective pasture management through rotational grazing is essential for optimizing livestock production and ensuring the profitability of your farm. A successful grazing management plan begins with balancing your stocking rate with available forage, not just the total acreage of your farm. Once you have a good inventory of the forages on your farm and their availability throughout the grazing season, you can start to plan a rotation. 

Rotational grazing can be as simple as closing a gate behind your livestock to protect the grazed pasture from overgrazing and allowing pasture regrowth. On a broader scale, some farmers opt to rotate their cattle once a day, allowing even small farms to maximize profit from the available pasture.

Rotational grazing limits the time of both grazing and recovery on each field on your farm. When grazing and recovery are out of balance, pastures are overgrazed, setting back the time it takes for regrowth and allowing undesirable weeds to take over. Similarly, undergrazing can lead to overgrowth, reducing the nutritive value of the forage and ultimately decreasing the productivity of the land.

Benefits of Rotational Grazing

Meat production per acre has been shown to increase when practicing rotational grazing. A study by the University of Georgia found that a twelve-paddock system with cattle rotated every two days resulted in a 38% higher stocking rate, 37% higher calf gain per acre, and 31% less hay fed per cow. With the potential to increase the carrying capacity of your farm by 69%, these are significant improvements and cost savings. For a 100-acre farm, you could increase the stocking rate from 25 cows on a continuous grazed operation to 42 cows on a rotationally grazed operation. If these calves are bringing in $1,250 each per year, those 17 additional calves would result in over $21,000 increased annual income.

Mike and Susan Clark operate 210 acres at their Green Acres Farm in Mascot, Tennessee. Family-owned since 1803, the farm saw a 66% reduction in hay feed after implementing strip-grazing in 2013.

“With the same herd of cattle our pastures last twice as long. Each time we divide our pastures we get twice as many cow grazing days.” says Mike Clark. 

Extend the grazing season with earlier spring production and a longer grazing season in drier and cooler months. This is a result of rotational grazing, where several paddocks are deferred from grazing and retained for lean times when forage production isn't as good. The more pastureland deferred from grazing and the higher the grazing height, the more grass will be available in the future when it is needed. 

Victor Shelton, retired agronomist and grazing specialist with the Natural Resources Conservation Service, extends the grazing season with this optimization.

"To improve efficiency, I focus on optimizing forage utilization while allowing it to recover properly. This strategy helps increase forage yield, enabling longer grazing periods and reducing my need for winter feed.” Victor Shelton.

In the same University of Georgia study, hay needs were reduced by 31%. On a farm that spends $210 daily on 3-4 rolls of hay, switching to rotational grazing can save around $8,000 over the 120 days of average hay feed per year. 

Forage utilization is the measurement of what actually makes it down your animal's throat, and it needs to be taken into consideration as you plan your forage needs. Utilization rates on a properly stocked operation can vary from 25% for continuous grazing to 75% for rotational grazing. That 50% increase in utilization is effectively doubling the size of your property. 

Higher forage utilization is dependent on the length of the grazing period, forage maturity, forage length, plant weight, and livestock stocking densities: 

• The more vegetative a paddock is, the higher its utilization. 
• Forage length is important, too; you want the animal to get a mouth full with each bite. Long, stringy grass or grass so short that they can't get a mouth full will impact utilization.   
• With a denser forage stand, the animals consume more forage per bite. It is recommended that animals consume no more than 50% of the plant weight in any single grazing. 
• Higher stock densities per paddock require more frequent rotations. 

Given all these factors, grazing for less than four days can lead to the most efficient use of resources.

More desirable forage species

Rotational grazing leads to a higher percentage of desirable forage species because it typically involves moving animals off a paddock before the preferred species are grazed below the minimum target height. In contrast, continuous grazing allows animals to consume the most palatable forage first, leading to overgrazing and a decline in desirable species, while less palatable forages and weeds increase to fill the available space. 

Minimum residual grazing height for various forage species

More palatable and digestible forages contribute to better animal performance. For example, orchardgrass performs significantly better than infected tall fescue, which can result in a gain difference of 0.2 average daily gain (ADG). If orchardgrass is overgrazed, the resulting loss in gains—valued at $2.50 per pound for steers—could equate to a loss of $0.50 per day. Over a grazing period of 300 days, this amounts to a potential loss of $150 per steer annually.

Nutrient savings are substantial for forage production when rotational grazing is practiced. Grazing animals typically remove only 20% of the nutrients from the forage they consume, meaning that 80% is returned to the pasture through excrement and urine. Rotational grazing ensures that these nutrients benefit increased forage production by returning them to the field. In contrast with continuous grazing, whereby nutrients are mainly deposited in shaded areas and around water sources, which can lead to environmental issues . 

It is generally accepted that every 1% of organic matter can release 25 pounds of nitrogen. The nutrients contributed by one cow's excrement and urine amount to 85-57-190 pounds per year of nitrogen, phosphorus, and potassium, respectively. With rotational grazing, most of these nutrients can reach the field, whereas continuous grazing leaves just 15% .

Improved soil functioning is directly related to rotational grazing, which results in numerous benefits. These benefits include enhanced water availability for forage due to better soil aggregate stability and increased organic matter. Additionally, improved air circulation in the soil reduces compaction and creates a more habitable environment for soil life. This leads to greater nutrient availability and a larger rooting mass, allowing plants to access more nutrients and moisture deeper in the soil. 

Ideally, soil composition should consist of 5% organic matter, 45% minerals, 25% moisture, and 25% air. Having higher organic matter levels would also be beneficial. Good rotational grazing management protects the soil with leaf cover and proper residue, lowering soil temperatures by 15 to 30 degrees, which reduces evaporation and further increases water availability.

This article was written in collaboration with expert agricultural consultant Greg Brann.

Greg Brann Consulting is renowned for Greg’s extensive knowledge of soil health, grass and livestock management systems, and plant identification. With over 40 years of experience in land and pasture management, Greg has developed tailored land management plans that offer practical ideas to help clients achieve their goals. With a BS degree in Plant and Soil Science and extensive experience as the State Grazing Land Soil Health Specialist, Greg brings a wealth of knowledge to his role.