May 4 2023 10:21 AM

Raising heifers on well-managed pasture can be a solution for many dairies.

The author is the grazing outreach specialist with University of Wisconsin-Madison Division of Extension.

ROTATING ANIMALS TO LEAVE a healthy level of pasture residual is key to an effective managed grazing system.

The title of this article may provoke the response: Why in this day and age would a dairy farmer ever consider grazing? Before you turn the page, consider that raising a heifer on pasture can reduce rearing costs by 50% or more. For the 450,000-plus replacement heifers in Wisconsin alone, that’s a combined savings of $100 to $200 million a year. Managed grazing may not make sense on many farms for the milking herd, but managed grazing of replacement heifers is a scalable practice worth considering.

Let’s explore how we got here.

The dairy industry has been changing for generations as farms have gotten fewer and larger. Yet, the iconic imagery of the red barn and green pastures is still used in media and marketing. Why do we continue to see this bucolic imagery when it represents the past? Perhaps those images invoke feelings of simpler times, or maybe it just feels good to pay homage to previous generations.

With that image representing yesterday, what does tomorrow look like? The evolution of the dairy industry has largely been an outcome-focused process which has, for the most part, left the past in the dust. The outcomes that have been the focus for decades have been yield — in the field and bulk tank, animal wellness, cow comfort, and even marketing. All of these outcomes translate to tremendous gains in productivity and efficiency. But what are the unintended outcomes of a singular focus on productivity? We cannot ignore that this evolution has coincided with a steady rise in farm closures and reductions in soil and water quality.

It is often said that challenges present opportunities. Tight profit margins and declining resources can be seen as problems or the cost of doing business, but in my opinion, that is a defeated viewpoint. Dairy’s unintended outcomes can be viewed as opportunities.

Opportunities are often missed when we focus solely on production-based, technological, and input-driven solutions. Solutions are especially overlooked when they resemble the past. What if the solution to tight profit margins and declining resources has been in front of us all the time?

Green results

More well-managed grazing would benefit farm economics across the country. Consider that, with Wisconsin’s 1.3 million dairy cows and an average cull rate of 38%, there are approximately 482,980 heifers being raised each year. At costs of $2.67 to $3 per head per day, heifer production costs range from $470 to $530 million annually. Using the University of Wisconsin-Madison’s Dairy Heifer Compass (, it is estimated that 180 days of grazing could save a farmer $1.67 per head per day, totaling $100 to $234 million in greater profits per year for Wisconsin dairy farms.

Managed grazing of dairy heifers can cut heifer raising costs 25% to 50% during the grazing season. A case study on a large dairy in Wisconsin compared 100 pregnant heifers raised on pasture for 180 days to heifers that were raised in a freestall barn. That farm was able to cut costs by 40% for that period of time, equaling a total savings of $27,000.

In addition to economic outcomes, there is the significant environmental component. Many farmers have embraced the principles of soil health on their cropland. Those include keeping the soil covered, minimizing soil disturbance, maximizing plant diversity, and maintaining continuous living roots. Yet, by choosing not to implement the fifth principle — integrating livestock onto the land — many farmers have not realized the full potential of soil health on their farm. By grazing replacement heifers, dairy farmers have a chance to achieve the full measure of soil health. Managed grazing stimulates soil biology in ways that harvesting cannot, indicating that livestock are the missing link for soil health.

Two “Rs” to keep in mind

The suggestion of grazing as a solution for today may sound preposterous and like a step backwards. But if there’s one thing I’d like you take away from this article, it’s that managed grazing is not your grandparents’ grazing! Well-managed grazing is a way to improve farm profitability and protect our natural resources simultaneously. Simply put, this type of grazing is different for two main reasons.

The first is residual. The foundation of any successful grazing system is a solid base of perennial grasses and legumes. But the way that forage is managed differentiates managed grazing from other types of grazing. Grazing of the “sward,” or above-ground growth, always leaves the bottom 4 to 6 inches ungrazed. Often, only 50% of the available forage is grazed at a particular time.

What is left behind, the “residual,” is allowed to regrow rapidly. When 50% of the plant remains, all of the energy captured from the sun is used for above-ground regrowth. If less than 50% of the plant remains, above-ground regrowth is stalled for up to 17 days while the plant restores its roots, which have been depleted from overgrazing. The simple step of leaving behind proper residual results in greater forage yield, better quality, and a longer grazing season.

A critical part of maintaining proper residual is rotation. In managed grazing, livestock occupy a “paddock,” a subdivided section of pasture, for short durations. In many cases, heifers are moved daily. Once they are moved, the paddock is allowed to rest for at least 30 days. Paddocks can be stocked with a high density of heifers for a short duration, but the stocking rate of the entire pasture must be low enough to allow for at least a 30-day rotation and 4 inches to 6 inches of residual through the season. If properly employed, a typical grazing season in Wisconsin spans from early May through early November.

Making it work

All this talk about the benefits of managed grazing is only worthwhile if it translates to implementation. The truth is that most dairy farmers choose not to graze. As I talk with farmers, I often hear that they don’t believe grazing is a bad idea, but there are some real barriers to putting it in practice. These include paying a mortgage on a building that sits empty for six months, putting fence back up after spending decades taking it down, the uncertainty of animal performance once taken out of the barn, a lack of labor and skills for grazing, the perceived sacrifice of good land, and in many cases, the scale of the operation seems too large for grazing.

But with all that said, there are farms of all sizes making it work. Many of these farms are finding creative and innovative ways to implement some heifer grazing into their operation. Annual cover crops and crop residues provide opportunities to graze for a period of time without acres dedicated solely to grazing. Some farms are providing custom heifer grazing as a service to other dairy farms in the neighborhood.

There are also emerging technologies for grazing that likely will play a key role in more implementation. One of those is virtual fencing, where heifers can be fitted with battery-powered GPS collars that are controlled by a smartphone app and keep cattle within their specific paddock without the need for physical fencing. This is a potential game-changer, especially for grazing annual crops.

In the end, dairy farms will need to address both tighter profit margins and soil and water quality concerns. Managed grazing is a flexible, scalable tool that can help address both issues, contributing to a more resilient and prosperous future for dairy.