Leverage the strengths of your grazing strategy

The author is a livestock area associate agent with the University of Arizona based in Cochise County.

There are advantages and disadvantages of every approach to grazing livestock regarding forage intake, plant growth, and time management.

Effective animal management is essential for maintaining healthy pastures and maximizing forage production. Whether you’re using continuous grazing, rotational grazing, or a flexible tactical approach, the strategy can significantly impact both your livestock and your pasture’s long-term health.

Each system has its own advantages and challenges, from the simplicity of continuous grazing to the enhanced forage utilization of rotational methods. Understanding these options and how they affect pasture growth, nutrient availability, and grazing intervals can help producers make informed decisions for healthier pastures and for more productive animals.

Continuous grazing: The simplest animal management method is continuous grazing, where animals stay on the same pasture for the whole growing season. This method requires less fencing and management but can lead to uneven grazing, overgrazing of desirable plants, and weed growth. Supplemental feed may be needed if pasture growth slows, and this system usually supports fewer animals compared to others.

Rotational grazing: Rotational grazing involves dividing the pasture into smaller paddocks that are grazed in sequence, allowing each section time to rest and recover. This promotes healthier plant growth, distributes manure more evenly, and reduces forage waste. The forage being grazed is newer, higher quality growth. Carefully managed rotational grazing may also help extend the grazing season, creating less reliance on stored feed. However, it requires more fencing, more frequent movement of animals, and the ability to provide water and supplements in each paddock.

Tactical grazing: A more flexible approach is tactical grazing, which combines aspects of both continuous and rotational systems. This method allows the producer to meet the changing needs of both animals and pasture throughout the year.

Rather than sticking to a set rotation of paddocks, the paddocks are grazed on a more flexible schedule. For example, continuous grazing of a section may work better during reproduction or for finishing livestock, while rotational grazing might be better to enhance pasture utilization, control animal intake, or encourage desirable forages species.

Regardless of the grazing system, having a sacrificial drylot area can be helpful during extreme weather like droughts or heavy rains. A drylot is a small area where animals can be housed and fed when grazing would otherwise harm the pasture. This protects the pasture and gives it time to recover, which offers even more flexibility to a tactical grazing plan.

Grazing intervals

Timing is key when it comes to grazing intervals. Delay the first harvest of a newly established pasture until most grass seedheads have emerged or legumes have flowered. This allows the plants to build a strong root system and store nutrients in their roots and stems, which they’ll need for regrowth and during the dormant season.

After the first harvest, aim to graze animals before seedheads emerge in grasses and before flowering occurs in legumes. This is when the forage is most nutritious and palatable, consisting mostly of leaves. As plants grow taller, the forage quality declines because stems are less digestible than leaves. Once plants begin to flower or produce seedheads, their nutritional value drops further, and they may become unpalatable to animals.

In the fall, stop grazing early enough to let plants reach full bloom before entering dormancy. After plants have become dormant, forage can still be removed through grazing or cut for hay.

Carrying capacity

Carrying capacity refers to the number of animals a pasture can support without damaging it, and this will vary across the country. On a well-managed pasture, 1 acre can typically support one animal unit equivalent (AUE), which is about a 1,000-pound animal or one cow. Smaller animals, like sheep, are considered a fraction of an AUE (for example, five sheep equal one AUE).

Pasture productivity varies by plant species and season. Cool-season plants grow best in early spring, slow down in summer, and pick up again in fall. Warm-season plants are most productive in summer. Little to no growth happens in winter in many regions, so supplemental feed may be needed during this time.

Animals on pasture typically consume 2% to 3% of their body weight in forage dry matter each day. Nonworking horses and dry beef cows eat around 2% of their body weight, while growing or lactating animals may consume closer to 3%. Remember that animals cannot utilize all the forage due to trampling and waste, with 40% to 70% of pasture growth typically being consumed.

In rotational systems, it’s essential to know the recommended resting and grazing periods for different species to calculate the ideal number of paddocks. Lower-growing species like bermudagrass have shorter rest periods that are generally less than four weeks, while species like alfalfa may need longer; however, rest periods will be affected by both local climate and seasonal variability. Grazing for about three days is often considered the maximum interval before animals start eating the regrowth, although up to a seven-day rotation may be common for farmer convenience.

Each grazing system has its pros and cons, and the best choice depends on the needs of your animals, pasture, and your schedule. Overall, continuous grazing is simple but may result in uneven pasture use, rotational grazing requires more effort but leads to healthier pastures and better forage use, and tactical grazing offers flexibility to adapt to the specific needs of your animals and pasture throughout the year.