Tag Archives: haying

Patch-Hay Grazing – Just Another of Many Ways to Create Habitat Heterogeneity

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Managing grasslands for biological diversity and resilience depends a lot on habitat heterogeneity. Every plant and animal in the prairie has its own needs and preferences related to factors like vegetation height and density, diversity of blooming flowers, the amount of exposed bare ground, and many others. To provide for all those needs, we have to manage in a way that provides all those habitat types.

Even more, we want to manage so that those various habitat types occur in different places each year in a kind of shifting mosaic of habitat patches. That allows mobile creatures to move to where they want to live, hunt, forage, mate, etc. It also allows plants to experience the growth conditions they like best at least every few years. As a result, no species consistently wins or loses and everybody stays in the game (persists in the prairie).

Sedge wrens (left) and upland sandpipers (right) need very different habitat structure for nesting. If you want both birds to nest in the same prairie, you need patches of tall/dense vegetation for sedge wrens and large areas of short vegetation for upland sandpipers.
Entire-leaf rosinweed (left) does well in prairies that haven’t been burned or grazed recently but daisy fleabane (right) is a biennial that does best after grazing or another treatment temporarily weakens dominant perennial plants. Consistent management in any particular place will likely eliminate one of these species over time.

There are lots of effective ways to create this kind of shifting mosaic and support a strong diversity of plants and animals (and other organisms). Foundationally, it just requires managers to split a prairie into multiple patches each year and make sure that each patch is both different from its neighbors and different than it was the previous year. Mowing, burning, and grazing are all ways to manipulate habitat structure and growing conditions.

All of those treatments can be applied at any time throughout the year, giving you a lot of options to play with. In addition, if you mow, you can vary the timing and number of times you mow a particular spot during the season, but you can also adjust the mower height each time. Grazing is even more flexible because you can vary timing, intensity, and duration to achieve a wide variety of results. Fire is the least flexible, but even so, you can burn during any season, as long as you have enough fuel (dry vegetation) present to carry fire. You may also be able to take advantage of fuel and weather conditions to create either a complete burn or a patchy one, depending upon your preferences.

If both fire and grazing are options for you, patch-burn grazing can be a terrific way to create a shifting mosaic. Within a patch-burn grazed prairie, large grazing animals (e.g., bison or cattle) focus their grazing in recently-burned areas much more than unburned areas. Managers burn a new patch each year to move the grazing pressure and rest around the grassland. We usually burn around 1/3 to 1/4 of the total site, depending upon how many years it usually takes for burned/grazed areas to fully recover. In drier and/or less productive sites, recovery from being burned and then grazed all season takes longer, so we burn a smaller percentage of the total area each year. Within that basic framework, there are lots of options regarding stocking rate, timing and duration of the grazing period, and more – allowing you to tailor the general approach to your specific objectives.

Patch-burn grazing at The Nature Conservancy’s Platte River Prairies. Cattle are focusing their grazing on a recent (summer) burn but have access to the unburned areas as well.

Patch-burn grazing, however, relies on frequent and consistent use of prescribed fire, which isn’t logistically possible for a lot of people. As a result, we’ve experimented with other approaches to “focal grazing” where we encourage grazers to do most of their grazing in one part of a larger grassland and then shift that focus patch around through space and time. One of those approaches is open gate rotational grazing, which takes advantage of the kind of fence and water infrastructure most ranchers already have, but creates more heterogeneity than most rotational grazing strategies. This summer, we’re testing virtual fencing as a way to influence cattle grazing patterns, and have a lot of optimism about that technology as well.

An additional method we’ve used over the years, and (finally) the topic of this post, is something we call patch-hay grazing. It’s not very complicated. It’s really just patch-burn grazing, but instead of burning, we cut hay where we want to focus grazing pressure. As with patch-burn grazing, the key is to create an area where fresh, nutritious grass growth, without any standing dead vegetation, lures grazers in and encourages them to spend most of their grazing time in that patch.

Cattle grazing in recently hayed prairie back in 2013.
Same prairie/year as above. You can see the edge of the unhayed prairie on the left side of the photo. The cattle had access to the unhayed area but spent little time there.

The results we’ve seen with patch-hay grazing have been very similar to patch-burn grazing, though we are still experimenting and learning. Both cattle and bison gravitate toward recently hayed areas and spend the majority of their time grazing there. That leaves the unhayed areas mostly ungrazed.

We’ve cut hay at various times of year across the growing season and have seen good success with everything we’ve tried. I’d say the biggest concern we’ve run into is that if we cut hay too late in the summer (e.g., late August), especially if we have a dry autumn, there isn’t always enough regrowth to lure grazers in. When that happens, they wander around and create small grazing lawns distributed across much of the pasture. The next spring, they tend to start on those small patches again instead of focusing solely on the hayed area. It’s not terrible, but the grazing isn’t as concentrated as we’d like.

This hay patch was cut in early August last year (2025). This photo was taken after cutting and before baling.
Here’s the equipment that was used.
Hay on the ground after cutting.
Here you can see part of the unhayed portion in the background.
This picture shows the same site the following spring (mid-April of 2026). The green patch is what was hayed in August of 2025.
Here’s a closer look at that hay patch. You can see the cattle (little black specks) grazing in the hayed area.

The nice thing about the concept of patch-hay grazing is that it can be incorporated into lots of situations. You can run it as a season-long grazing system as we usually do – cutting hay to concentrate grazing in one area more than others. But you can also mix some hay harvesting into just about any grazing approach. If there are parts of a pasture cows don’t often graze, you could hay those areas (assuming topography allows it) to encourage more grazing pressure. You could also incorporate haying into a rotational system. You could mow portions of several pastures, for example, to create more patches of higher forage quality and increased habitat heterogeneity at the same time. There’s plenty of room for creativity, depending on what you’re trying to accomplish.

Regardless of the tools and techniques you use, a focus on habitat heterogeneity and a shifting mosaic can help you support the broadest possible diversity of species in your prairie. That diversity is important for its own sake, of course, but it also props up the ecological resilience of the site. Given the raft of challenges facing prairies today, the more resilient we can make them, the better.

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Notes on hay-patch grazing logistics: For those who are interested, here are a few additional things we’ve learned.

First, we have had no problem with cutting hay while cattle are in the pasture. The cattle started grazing the hayed area almost immediately after the mower went through and walked between the wind rows without messing them up.

Second, lower mowing heights seem create more attraction for grazers than when the hay mower is set higher. I assume that’s because there is less thatch and old material present, but I don’t know for sure. It’s just what we’ve noticed.

Third, you might wonder if you can just mow instead of cutting hay and baling/removing it. Sure, but a bunch of dried material lying on top of the green regrowth counteracts a lot of the attractiveness of that regrowth. Now when a grazer takes a bite, it’s probably going to get some old dead stuff in its mouth along with the new green growth it really wants. Mowing may still work if the rest of the pasture is tall and dense because the mowed area will probably be more attractive than that, but it’s certainly not as good as haying.

Finally, you might wonder how to calculate a stocking rate when you’re cutting and removing a bunch of forage from the site. When we figure stocking rates for patch-burn grazing, we start with the recommended stocking rate (based on soils, rainfall, etc.) for the whole pasture and that’s usually pretty close. Often, we find ourselves bumping that rate up over the first several years until we find the sweet spot where we get good grazing pressure in the burned areas but light enough grazing elsewhere that previously burned patches recover within a few years.

We calculate stocking rate the same way when we cut hay instead of burning. It feels like we’re able to graze as normal while still cutting hay from about 1/3 or 1/4 of the site. I’m not really able to explain that because it seems like we’d be removing some production from the site and reducing the amount of available forage. One reason might be that we typically mow the tallest and most rank grass, which the cattle weren’t going to be grazing anyway. Regardless, we’ve never yet had an issue with using the same stocking rate as we’d use with patch-burn grazing.

Oh, and it hopefully goes without saying that any of the general approaches here will still require managers to watch and adapt management over time. In addition, there will surely be additional work needed to help suppress invasive species and/or encroaching woody plants, or whatever other challenges your individual prairie faces. None of these approaches should be seen as a recipe that, if followed, will cover all the needs of a prairie.

The Myth of Self-Sustaining Prairies

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Here’s a question I get asked occasionally:  “At what point will my prairie become self-sustaining?”

There are lots of ways “self-sustaining” can be defined, of course, but usually the person is hoping that at some point they can just step back and let the prairie do its thing with very little or no human input.  In other words, they hope the prairie will function like a machine.  Once you have it tuned up correctly, it’ll hum along just fine with only occasional inputs of fuel or maintenance.

Ah, that it would be so easy.  Unfortunately, there is a short answer to the question, and it’s a disappointing one.  The answer is, “It just doesn’t work that way.”

Here’s the short explanation of that short answer:

A prairie with no management at all accumulates thatch from each successive year of plant growth, and if not removed, that thatch eventually builds up to the point at which only a small number of plant species can survive.  Unfortunately, the most dominant of those surviving species tend to be either trees/shrubs or invasive plants.  In the eastern half of Nebraska, smooth brome tends to be a primary winner, along with tree species such as Siberian elm and eastern red cedar.

Besides the issue of thatch build-up, there are just too many threats, particularly from invasive species and trees, for prairies to maintain their species compositions and ecological functions without human management.  This is particularly true with tallgrass prairies in an agricultural matrix.  The degree of vulnerability to invasion depends upon soil type and the surrounding landscape.  Some soil types seem favor invasives more than others – oftentimes, high soil nitrogen levels can favor exotic grasses, for example.  The degree of invasive species pressure on a prairie is also influenced by the abundance and proximity of those invaders in the neighborhood around the prairie . However, all prairies (that I’m aware of) have some degree of vulnerability to invasive species.

Active management, such as the application of prescribed fire, is needed to prevent excessive thatch buildup and to help suppress invasive species.

That’s the short answer.  A longer and better answer is that tallgrass and mixed-grass prairies are not “climax communities” in the classic sense.  In my early ecology classes, I learned that terrestrial plant communities move through a process called succession from bare ground to some final stable state – usually a forest.   Bare ground is colonized by opportunistic species, which are eventually pushed out by longer-lived grasses and wildflowers.  Those grassland species are then replaced by various generations of tree species, each topping out the other until a final set of tall long-lived trees becomes dominant and creates a stable community.  Disturbances such as fire or severe weather events might set back succession temporarily, but the process keeps moving toward that climax community.

Prairies don’t fit that successional model very well.  Prairies are maintained (and defined?) by disturbances such as fire, grazing, and drought.  Without some combination of those ecological processes, prairies turn into woodlands.  Because of that, some might argue that prairies are simply an ephemeral stage of the longer successional process, and not really a stable ecosystem.  Others might argue that the whole idea of ecological succession is overly simplistic and not representative of the way all ecosystems function.

Without getting into that larger argument, the real point is that if we agree prairies are important, and we want to maintain them, active management is necessary.  Some people point to expansive prairies in Great Plains landscapes and wonder if those prairies could maintain themselves without humans if given the chance.  After all, lightning-caused fires and roaming herds of bison should be able to take care of things without interference from people, right?  In reality, we don’t have any historical precedent to back that up.  Today’s prairies have only been around since the last ice age –  about 10,000 years (less in the east, more in the west.)  During that entire time, people have been active managers of those prairies.  Fires set by Native Americans were much more abundant and extensive than lightning-caused fires.  Bison herds, and many other herbivores, responded to those fires by focusing grazing in those recently burned areas.  That intensive fire/grazing disturbance interacted with and compounded the impacts of long droughts, floods, and other weather-related events.  Cumulatively, those major disturbances maintained the integrity of prairies.

Along with climate and fire, bison (and other grazers/herbivores) were a major force that shaped prairies. However, people and their activities were also an important component of the process.

There’s really no way (and no reason) to separate people from prairie.  Regardless of the intent or motivation of the people who manage prairies – historically or now – their actions have tremendous impacts.  Similarly, inaction by people who control prairies has tremendous impacts as well.  In the natural resource management world, the phrase “No management is still management” is well-worn but nevertheless true.

Of course, defining the need for continual human management – even in the absence of today’s new challenges such as invasive species – doesn’t solve the problem.  What kind of management is needed?  How do we know when to do what?  The answers to those questions are complex, still being debated, and the primary subject of this blog, my book on prairie management, and myriad discussions among prairie managers around the world.

Some people who agree that prairies require some level of active management still search for a relatively simple management recipe to follow.  Annual haying or burning or two to three-year rotations of fire or grazing are examples of management regimes that are commonly used and advocated for.  This is really just a small step up from the idea that prairies should maintain themselves.  In this case, the argument is that prairies should be able to maintain themselves if we just provide them the right basic disturbance framework.

I’ve given my opinion on simple, repetitive management regimes often within this blog (see my Calendar Prairies post as an example).  I think repetitive management threatens plant diversity because there are always some plant species that are favored in a particular management regime and others who are not.  Over time, those species not favored will inevitably fade out of the community if the same regime is applied over and over.  Perhaps more importantly, animal species – including insects – with fairly specific habitat structure requirements are similarly affected.  Some species thrive under repetitive management if that management consistently favors them.  However, those animals that don’t find what they need in that management system can’t normally survive for many years in suboptimal habitat like many perennial plants can.   Animals without appropriate habitat either move or die – and in fragmented landscapes, or in landscapes where the same management is in place across the entire landscape, moving may not be a viable option.

Annual haying provides good growing conditions for many plants - especially those the bloom and produce seed prior to the haying date. On the other hand, some of the plant species favored by annual haying (including smooth brome) can become invasive. In addition, some desireable native plant species do poorly under annual hay management and eventually disappear from those prairies.

All of this adds up to one conclusion.  Diverse, functioning prairies require active, constant, and thoughtful management by humans.  There’s no getting out of that responsibility.  If we choose not to be active thoughtful managers, we are choosing to let prairies degrade, and we’ll have to live with the consequences (“No management is still management”).  Hopefully, though, most people with influence over the management of prairies will embrace their role, and be active managers – as well as active participants in ongoing discussions about the impacts of various management techniques and systems.

Though active prairie management is time-consuming, and often expensive, it’s also extremely rewarding.  Whether it’s a small backyard prairie garden, a 20,000 acre grassland, or something in-between, every year is a chance to try new things, see what happens, and learn from the experience.  More importantly, the diversity of plant, insect, and invertebrate species in well-managed prairies – large and small – is its own reward.  Who could ask for more than that?