Category Archives: Prairie Management

Open Gate Rotational Grazing

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An alternative approach to facilitating wildlife and plant diversity in grazed prairie.

UPDATE as of October 2022 – since writing this in 2017, we’ve gained five more years of experience with this and it’s still working very well.  In addition to seeing great habitat heterogeneity, we also have pilot data on soils that look great and have embarked on a four year project to look more deeply (haha) into that subject.  I gave a 20 minute presentation on the approach at the 2022 Great Plains Fire Summit, which you can watch here if you like. 

Based on the last 20 years of experience and data collection, the shifting mosaic approach to habitat management seems to support plant and animal diversity and foster ecological resilience in our prairies.  One of the most important parts of our shifting mosaic management is that each patch of prairie goes through a progression of season-long intensive grazing, followed by a multi-year recovery period.  At any time, only part of a prairie is in each phase of the system (intensive grazing, early recovery, late recovery), so there is always a variety of habitat structure available (short, “weedy” and tall) for wildlife.  In addition, as that grazing/recovery progression occurs, plant species experience a different set of growing conditions each year.  Regardless of its competition ability or strategy, each plant is ensured favorable conditions for its growth and reproduction at least once every few years.  Based on our long-term data sets, our management has sustained plant species richness, and both conservative and opportunistic plant species are persisting in our prairies.

A fenceline contrast at our family prairie shows the kind of habitat heterogeneity found in a shifting mosaic approach to prairie management.

Patch-burn grazing is one way to create a shifting mosaic, but it’s certainly not the only way.  While patch-burn grazing has some attributes that make it easy to implement (no need for cross fences or moving animals during the season), it does require regular application of prescribed fire, which can be difficult for some landowners.  In addition, patch-burn grazing is very different from the kinds of rotational grazing systems many ranchers are comfortable with and have set up their pastures for.  We’ve been experimenting with an approach to creating a shifting mosaic that keeps many of the wildlife and diversity-friendly attributes of patch-burn grazing but might fit better within the comfort zone and logistical framework of many ranchers.

For lack of a better idea, I’m currently calling this approach “Open Gate Rotational Grazing”.  It is not a rigid prescribed grazing system, but rather a general and adaptable way of managing multiple grazing paddocks within a prairie.  It’s similar to a traditional deferred grazing strategy, but with one big difference.  In most rotational grazing systems, cattle are moved from one pasture to the next, closing the gate behind them to allow the previous paddocks to rest.  In the open gate system, when cattle are presented with their next paddock, the gate behind them remains open – allowing the cattle to continue grazing the initial paddock even as they have access to new grass.

In a traditional rotational grazing system, cattle are progressively moved through a series of paddocks, closing the gate behind them.  In a deferred rotational system, at least one paddock is usually rested for the season.

Under an open gate approach, gates are left open when new paddocks are made available, allowing cattle to graze both the new paddock and the one(s) they had been grazing before. 

The idea started one year when we weren’t able to get a burn done in a prairie under patch-burn grazing management.  Since we didn’t have a burned patch to focus cattle grazing, we instead used electric fence to concentrate the cattle in the area we’d hoped to burn.  We kept them in the enclosure until they had it grazed pretty short.  Then we removed the electric fence and allowed cattle to access to the whole site.  For the remainder of the season, the cattle continued to focus most of their grazing in that former enclosure, attracted by the tender regrowth.  As a result, the overall grazing pattern was fairly similar to what we’d expect with patch-burn grazing.  Seeing how strongly cattle were drawn back to where they’d grazed earlier provided the seed for the open gate rotational system.

On my family prairie, I’ve been using the open gate approach for the last several years.  I have four paddocks, and I basically think of the gates between those paddocks as relief valves.  We start with the cattle in one paddock, and when they have grazed most of the grass down in that pasture, I open the gate to an adjacent paddock so they have more options.  The cattle can keep grazing the regrowing plants in paddock #1, but they aren’t forced to eat more than they want to in that paddock because they have another whole paddock available to them.  If the cattle graze down most of the plants in the second paddock, I can open a gate to a third paddock and provide them with even more options.  I keep the fourth paddock closed off for the entire season so it can rest.

The result of an open gate approach is that one paddock is grazed all season long, one is rested all season, and the others have intermediate levels of grazing.  This results in heterogeneity of habitat structure as well as a wide range of growing conditions for plants.  Each year, grazing starts in a different place, shifting the disturbance regimes among the various paddocks.

In the above example, paddock A would rest the following season and the grazing rotation would start with paddock B.  Paddock A would rest for a full year and most or all of the next year, giving it lots of time to recover vigor.  The grazing pattern for each paddock is as follows: grazed 2nd half of the season, grazed all season, rested, rested/grazed only late season if needed.

The open gate approach can be used with just about any rotational grazing system, as long as there are adjacent paddocks that can be opened up.  One key component of the open gate approach is that paddocks grazed early in the season continue to receive grazing pressure for the rest of that season without forcing cattle to eat progressively lower quality forage as the season goes on.  Instead, cattle can regulate their diet freely, choosing between previously grazed areas and those they haven’t yet grazed.  Typically, when cattle are given that kind of choice, they eat very little other than grasses.  This works out well for pollinators because it means many wildflowers are allowed to grow and flower amongst grazed grasses.

At our family prairie, the open gate approach seems to be helping with our continuing quest to increase plant diversity in areas formerly dominated by grasses.  New plants are introduced via overseeding (after a season of intensive grazing), and then persist under our grazing management.

In the open gate system, there is great flexibility about when, and how intensively, each paddock is grazed each year, though some of that flexibility depends on how the paddocks are arranged.  Ideally, all the paddocks would be connected through a single hub so the manager can choose to open any gate to any pasture, as needed.  However, my family prairie doesn’t provide that amount of flexibility (the four paddocks are arrayed in a donut-like loop, with no way to connect them through the donut hole) and the approach still works.  Most of the time, the paddock grazed most intensively one year gets complete rest the next.  However, the pattern of grazing each year always depends upon how I think recovery from previous years’ grazing is going.

I think there are great benefits to longer grazing periods and longer rest periods than are typically found in rotational grazing systems.  Certainly, those prolonged grazing and rest periods can provide a greater variety of wildlife habitat conditions, especially on the shorter and taller ends of the vegetation structure spectrum.  In most rotational grazing systems, cattle are moved out of a pasture before grasses are grazed very short, allowing them to recover quickly.  In addition to reducing habitat heterogeneity, that approach can favor strong grass dominance at the expense of wildflowers and plant diversity.

Even when grazing pressure is intense within each paddock of a traditional rotational system, short duration grazing may not foster habitat heterogeneity.  For example, if a paddock is grazed hard in May, it might suppress cool-season grasses, but warm-season grasses won’t be much affected, and once cattle are removed, summer vegetation will fill in quickly, resulting in vegetation structure of moderate to tall height.  The same can happen with summer grazing bouts followed by fall growth of cool-season grasses.  By maintaining grazing pressure for the entire growing season, two things happen.  First, there is sustained short vegetation structure for wildlife that need it.  Second, and perhaps more important, all dominant grasses are weakened by that long term grazing, leading to a fairly long recovery period (1-3 years, depending upon grazing intensity and geographic location), during which wildflowers and other plant species are temporarily released from that grass competition.  That long recovery period creates terrific wildlife habitat and also helps sustain plant diversity.

While prescribed fire isn’t necessary in open gate rotational grazing, it can certainly be incorporated.  The paddock to be grazed all season could be burned before the season starts, for example, which would further add to its attractiveness to livestock (and remove eastern red cedar trees, excess litter, etc.).  At my own prairie, I haven’t been using fire for a variety of reasons, including that I’m so busy burning for work I don’t have time/energy to burn my own place.  So far, I’ve been happy with the way the prairie is responding in the absence of fire, but if I can get myself better organized, I wouldn’t mind doing some burning.  If nothing else, it would mean less time cutting little cedar trees with loppers.

Prescribed fire is not a strategy all ranchers are willing or able to include in their operations.  The open gate approach provides options for creating a shifting habitat mosaic without relying on regular prescribed fire.

I don’t have many years of experience with this open gate approach, or much data to help me understand all the nuances of its impacts on flora and fauna.  However, what I’ve seen from early experiments seems promising.  I’m sharing the idea and our experiences so far, not because I’m endorsing the open gate approach as the next big thing, but because I hope others might find ways to try it and report back.  Because the basic idea is as simple as not closing a gate when opening a new paddock, it can be employed in many different scenarios if people see potential for it.  Also, I’m not trying to claim or patent the idea, and I’d be shocked if there aren’t people reading this that have already tried it in various forms.  If so, I’d love to hear about it.

A Hopeful Metaphor for Prairie Managers

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Recently, I listened to a conference presentation by Doug Ladd, the Director of Conservation for The Nature Conservancy in Missouri, and one of the smartest people I know.  Doug talked about the importance of conserving biodiversity, habitat diversity, essential ecological processes, and irreplaceable habitats and species, and stressed the need to better connect people with nature.  It was an excellent talk, and I could spin many of his points into entire blog posts.  For now, however, I want to focus on one short phrase he uttered, which relates to something I often think about.  The phrase was “There is no endgame in conservation.”

The importance of that phrase might not strike you immediately, but for those of us who dedicate much of our lives to prairie conservation, it’s an idea we need desperately to come to terms with.  No matter how much time and effort we put into restoring or managing prairies, we won’t ever reach a place where we can stop and just let nature handle the rest.  Many people harbor the romantic notion that if we could make prairies big enough and provide them with their full complement of species – including everything from soil microbes to bison, we could step away and the system would run itself without human intervention.  Unfortunately, that’s just not the way it works.  Nature relies on people just as much as we rely on nature, and it’s really not even fair to mention nature and people as if they are two distinct entities.

Even in places like the Nebraska Sandhills, with roughly 12 million mostly contiguous acres of prairie, the role of humans is still critically important and necessary.

Because there is no endgame in prairie conservation, we need to develop an appropriate mindset. Most importantly, we have to be able to look at the future without despair.  As an example, it’s easy to look at many grasslands and wonder how we can possibly deal with all the invasive species threatening the site today, let alone all the new ones that will inevitably join them.  It can feel like trying to hold back a river with a garden hoe.  Issues like habitat loss and fragmentation, nitrogen deposition, and climate change just make the picture even more bleak.  Knowing that our prairies won’t ever be able to stand on their own might seem the same as knowing that we can never win.  All we can do is stave off loss for as long as possible.  That’s seriously depressing.

Since this is the life I’ve chosen for myself, I’ve thought a lot about the idea that there is no endgame in conservation, and I’ve come up with a metaphor that makes me feel a lot better about it.  I don’t see myself as a hopeless defender of prairies, trying to stave off inevitable destruction.  Instead, I see myself as part of a long series of mechanics.  I inherited the prairies I work with from prior mechanics, and someday I’ll hand those prairies off to future mechanics.  As such, my job isn’t to save the prairie, it’s to keep it running until the next mechanic takes over.  The metaphor applies to an individual manager and a single prairie, but it also applies to each generation of conservationists and the earth we’re all working to maintain.  Success is being able to hand off a functioning prairie, biome, or earth to the next generation of mechanics.

To understand my metaphor, you have to move away from the idea that most mechanics are only able to keep a particular car, for example, running for a certain period of time before it inevitably dies and goes to the scrap heap. While that is the way it usually works, it doesn’t necessarily have to be.  Imagine starting out in 1908 with a brand new Ford Model T automobile and giving a series of mechanics the charge to keep the vehicle functional forever.  For a while, keeping the car running just means replacing fluids and parts that break or wear out.  Eventually, however, there will be needed updates to parts, and even changes to the overall design of the car, so it can be adapted to keep up with a changing world.  Over time, because of changes in road design, safety and fuel efficiency rules, and needs of drivers, the car will have to be made to drive faster, brake more efficiently, use different fuel, and evolve in numerous other ways.  As each generation of mechanic finds innovative ways to keep the vehicle on the road and running well, the vehicle will be continually and repeatedly transformed.  Today’s version of the vehicle would be nearly unrecognizable to the mechanic who first worked on the Model T.  Very few original parts would remain, but today’s version of the vehicle would still perform the same essential function of transporting people and/or goods from place to place.

Prairies and other ecosystems are both easier and harder than cars to maintain over time.  On the one hand, prairies are infinitely more complex than cars, and come with many more challenges (though auto mechanics might argue that last point).  On the other hand, prairies consist of networks of living organisms, which can adapt as individuals and as communities to evolving challenges.  That inherent adaptability means that the prairie manager’s job is really to help the prairie maintain its resilience – its ability to retain its essential functions – as the world changes around it.

Just as the vehicle in my mechanic metaphor is constantly transforming, prairies and other ecosystems have to do the same, and land stewards have difficult choices to make as those changes occur.  As an example, many of today’s prairies have numerous and abundant species that weren’t even on the continent a few hundred years ago.  A profusion of introduced plants have entered the scene, some of which are apparently innocuous, and others that have dramatically changed the balance of power within plant communities.  In addition, white-tailed deer have become superabundant across most prairie regions, pollinator populations are crashing, and many other changes to animal communities have severe impacts on ecological processes.  Belowground, non-native earthworms and pill bugs are just two examples of species that have fundamentally altered the soil fauna in ways we don’t really understand.  Habitat fragmentation, high levels of nitrogen deposition, and a rapidly changing climate all combine to further drive important transformations in prairie species composition.

Yellow bedstraw (Galium verum) is a yellow flowered plant that seems to be invading low meadows in portions of the Nebraska Sandhills.  Making decisions about whether and how to address invaders like this can cause a lot of anxiety for land managers.

Fortunately, our job as land stewards is not to prevent our prairies from changing; our job is to help prairies preserve their character and function as they change, and then hand those prairies off to the next generation of stewards.  How do we do that?  We can manage for plant diversity and habitat heterogeneity to maintain ecological resilience.  We can prevent or suppress invasive species that have serious negative impacts on that resilience and diversity.  We can enhance the viability of small isolated prairies by restoring adjacent habitats and making those prairies larger and more connected.  As time goes by and conditions change, prairies will transform in ways that might make them nearly unrecognizable to land stewards of previous generations.  Rather than a sign of failure, those transformations are a sign of success, as long as they preserve the components and processes that are characteristic* of prairies.  After all, a 2017 Tesla Model 3 is a far cry from the 1908 Ford Model T, but which would you rather drive through today’s world?

*Defining the essential characteristics of prairies is something we don’t discuss nearly enough.  It seems like a simple enough exercise to outline what makes a prairie a prairie, but if you believe that, give it a shot…

Prairies like this are surely very different today than they were in the past or than they will be in the future. Change is good and healthy, as long as we can preserve the essential components and processes that define and sustain prairies and prairie communities.