It’s wrong to assume that successful restoration or management tactics from one prairie will work in another. Instead, every prairie has its own “personality” and responds accordingly. The key to success is experimentation and adaptive management.
Bill Kleiman is one of my favorite people. We have much in common: a love of prairies and restoration, a drive to learn from our mistakes and share what we learn with others, and a strong belief in the importance of conservation. We’ve both worked for The Nature Conservancy for a long time (he’s got a couple years on me) and have been co-leading the Grassland Restoration Network for the last several years. He’s also a great guy and a good friend.
However, despite the fact that Bill and I are friends and have a lot in common, there are some big differences between us as well. Bill is much more patient than I am, and better at the social niceties needed to build close relationships with neighbors and volunteers. I tend to say what I think – sometimes inappropriately. Bill is not shy about expressing his opinion, but does it less frequently, and usually with kindness and self-deprecation.
Bill and I both manage grasslands for The Nature Conservancy, but just as there are differences between us as people, there are also some stark differences between our sites and the approaches we take toward prairie restoration and management. Bill’s site, TNC’s Nachusa Grasslands, is located in rolling hills about two hours west of Chicago, Illinois. My Platte River Prairies are on mostly flat alluvial (river-formed) soils in south-central Nebraska. As a result, the soils, topography and climate vary greatly between the two sites. Moreover, our sites each have unique land use histories, invasive species legacies, and social and cultural contexts.
I was thinking about all of this last month as our Platte River Prairies crew traveled to Nachusa Grasslands where Bill and his team were hosting this year’s annual Grassland Restoration Network workshop. It was fascinating to compare the land management and restoration strategies we each use, especially knowing that both of us have diligently tested and refined our methods to meet the individual challenges of our respective sites. Below are some of the similarities and differences between our approaches.
1. Seed Mixtures and Seeding Rates
Both Nachusa Grasslands and the Platte River Prairies have been actively restoring cropland to high-diversity prairie habitats. At both sites we broadcast our seed (as opposed to drilling it). The seed is broadcast either by hand or with a drop spreader – a fertilizer spreader that drops seeds onto the ground. In fact, broadcast seeding is the technique of choice for the vast majority of sites that participate in the Grassland Restoration Network. (You can learn more about fairly universal strategies and tactics in the “Lessons from the Grassland Restoration Network” document several of us put together.)
However, while we both broadcast seeds, Bill has found that successful prairie plantings at Nachusa require much heavier seeding rates (around 50 bulk pounds of seed per acre) than we use along the Platte River (8-10 bulk pounds). Bill’s seed mixes include lots of seed from wildflowers, sedges, and “subdominant” grasses such as little bluestem, prairie dropseed, and sideoats grama, but almost no seed from more dominant grasses such as big bluestem and indiangrass. In our Platte River Prairies seed mixtures, dominant grasses make up about half of the weight of the mixture.
Both Bill and I have experimented with many variations of these seed mixtures and have settled on these broad recipes as appropriate for our respective sites. Though we do things differently, we both end up with very diverse prairies that meet our objectives. When Bill uses lighter seeding rates, his new prairies get swamped out by invasive species before native plants become well established. He’s also found that adding dominant grasses to the initial seed mix leads to plant communities that become overly grassy and not very diverse. In contrast, using lighter seeding rates on the Platte allows us to plant more acres per year with the same seed harvest effort, and while it takes longer for our plantings to establish, they still end up being very diverse. As our plantings mature, fire and grazing management helps suppress the dominance of big bluestem and indiangrass and maintain high plant diversity.
2. Weed Control in New Restored Prairies
Weed control strategies for new plantings also vary greatly between Nachusa Grasslands and the Platte River Prairies. At Nachusa, Bill and his crew walk every inch of new plantings multiple times each year until the native plant community is well established. They remove (by pulling or spraying) every invasive plant they find – focusing mostly on perennial legumes such as birds foot trefoil, crown vetch, and sweet clover. Once the native community is established, they can relax a little, but they still watch each site very closely. In some cases, they’ve not been able to keep up with the pressure from invasive plants and they’ve made the difficult decision to just give up and start over, rather than fighting a losing battle for years.
Our weed control on the Platte River Prairies looks much different. We don’t really have problems with perennial legumes or other non-native forbs. In fact, we pretty much ignore sweet clover, and most other “weeds” during the establishment phase of a new prairie are annuals such as foxtail, marestail, and annual sunflower that just fade away as perennial prairie plants take over. Our major fears have to do with perennial invasive grasses, such as smooth brome and Kentucky bluegrass, and we deal with those mainly by suppressing them with fire and grazing management. We also worry about deciduous trees, such as Siberian elms, that we have to control with herbicides because fire and grazing don’t do the job. However, during the first few years of establishment, while Bill and his crew are painstakingly patrolling their sites, we can mostly ignore our new plantings – except for an occasional prescribed burn to limit the buildup of thatch.
A third difference between our sites has to do with overseeding. In both remnant (never plowed) and restored prairies, we occasionally want to add missing plant species. At Nachusa, they just burn the prairie and throw the seed out on the bare ground – and it works! In our drier Platte River Prairies, we’ve not had very much luck with that strategy. Using grazing to weaken the dominant grasses seems to help us get better establishment of new plants because it suppresses competition for moisture and other resources. Bill’s crew doesn’t seem to have to worry about that – even in sites with lots of grass.
Bill and I have done extensive experimentation to come up with effective prairie restoration and management strategies at our respective sites, and we continue to adapt as we go along. We can learn from each others’ experiences, but there is also much that doesn’t translate well between sites. Some of that is due to the distance between Nachusa and the Platte, and the corresponding differences in climate and soils. However, even prairies that are much closer together can respond very differently to management and restoration tactics. Soil types, seed banks, topography, management history, landscape context, and many other factors combine to give every prairie it’s own “personality”.
It might seem overwhelming to learn that every prairie requires a unique set of restoration and management strategies, but it’s really not that bad. There are a still a lot of commonalities between prairies – just like there are many similarities between Bill and me. However, just as you would need to consider differences between Bill’s personality and mine in terms if you wanted a positive response from us, the same holds with prairies. (If you want a favor from Bill, you might want to invite him to a little gathering and serve good beer. On the flip side, if you want something from me, pizza would make a better bribe, and while I’m not against parties, the less small talk needed, the better…)
Above all, beware of anyone who tells you’ve they’ve figured out the magic formula for how to manage or restore prairies. It’s just not possible. Instead, take a look at what others do, learn from their experiences, and then experiment with a variety of techniques at your own site. It won’t take long to figure out what moves your prairie in the direction you want. Fortunately, unlike Bill (I’m kidding!) prairies are pretty forgiving, so if you try something and it doesn’t work, they aren’t likely to hold a grudge.
P.S. Bill will be appalled that I’m giving him so much credit for the work at Nachusa. Clearly, both Bill and I have crews of staff and volunteers that do most of the work and much of the thinking. For this post, however, I was trying to build an illustration of personalities in people and personalities in prairies. It was a lot easier to do that by focusing just on Bill and me. Please understand that the ideas and work of Nelson, Cody, Mardell, Hank, Becky, Karen, Al, Bernie, Jay, Susan, Leah, and many others are represented here as well. (There, does that make you happier Bill?)
How incredible that Bill and the team go out over their prairies inch by inch. It reminds me of when kids would walk beans back in the old days before herbicides killed everything in sight. It was a great way for kids to earn money (unless they were walking their own fields. *grin*). I love the diversity of the prairies here and in Illinois. Having been born in Chicago and having to adapt to prairies later in life; I am fascinated by the changes from East to West. I have studied “nature” and learned my appreciation for Nebraska’s environments from Fran Kaye. Before that, I was disheartened by the lack of Autumn color.
Did I remember to ask you why the dominant color of flowers in the Autumn is yellow?
Not sure why so many late season flowers are yellow… Good question!
Instead of talking in percentages, how about how many bulk pounds of dominant grass seed you spread per acre vs how many Bill spreads? Granted, he’s spreading 4-5x the total pounds of seeds per acre, but the pounds of dominant grasses may be around the same. That could be an interesting way to look at the same concept. Maybe it’s the forbs and subdominant grasses that are having issues getting established and the dominants are fine with either location.
Jon, it’s a good point. In this case, however, he’s definitely using less big blue and indiangrass than we are – almost none, in fact. (Sometimes literally none)
A third person who should be mentioned for a comparison of notes is Stephen Packard. Stephen spreads seed very thinly into a cover crop. The cover crop creates a fuel matrix for burning. Burning helps keep woody species from invading, which can locally be a larger problem than legumes in some instances. Once the cover crop has been burned a few times it begins to thin out. The prairie seed is hand broadcast into the weaken matrix. Stephen has been able to get a number of very conservative species to establish by sowing seed or planting into sites prepared with the above method. This being said, I do wish the seed had been broadcast more thickly. However, the public land owner has set limits on where the seed can originate which are so limiting that more seed could not be obtained for the ambitiously large area.
I can definitely see why Bill would use such a large amount of seed per acre since he seeds into plowed ground. Weeds take advantage of an open niche really quickly even when the effort has been made to eliminate them from the site. Sometimes success with controlling weeds has much more to do with what your neighbors are doing rather than what you do. Even if you eliminate the sweet clovers, the deer eat it and are going to bring it back into your restoration if it is on your neighbor’s property. Any open niche, for example spots where herbicide has killed the vegetation or a burn scar, is preferentially colonized by a variety of weeds.
In contrast, the sweet clovers are not a problem at your sites because grazing keeps them from dominating. A good way to compare is to look at the difference between grazed prairies and ungrazed road right-of-ways. The road right-of-ways are usually full of dense sweet clover.
I expect Bill will find he needs less seed per acre when doing restoration with grazers. The fact that grazing helps control the sweet clovers reduces a significant labor requirement and makes success more probable.
I am still surprised that you have not had success with over seeding. I wonder if the difference is because Stephen, Bill, and you determine success differently?
I have been considering what Stephen and you do differently when over seeding. You broadcast seed evenly over an area. Stephen instructs volunteers to strategically sow seed into micro sites where the chance of survival is larger. I wonder if you could dramatically improve your success if you took a more strategic approach to the placement of seed. I think the extra effort required to sow seed into favorable locations would be worthwhile considering the effort required to obtain quality seed.
See Stephen’s related Blog Post “Where to Broadcast our most Precious Prairie Seed?”
Another nice essay, Chris. I agree with your points about tailoring our strategies to fit our sites which in this case are far enough apart in soils and rainfall to respond differently. Not sure what grazing will do. Glad we are doing lots of baseline data gathering. Yes, Nachusa is a bunch of people.
Have a question on group pictures of people on field trips. How are the best ones composed? The typical circle of backsides in the foreground and faces in the distance seems to tell no story other than folks were listening to someone in a circle. Any hints on how to zip up these photos? We have the same kinds of problems with field trip pictures in the VT woods only ours have photo bombing tree trunks. Thanks! Tom P.
Adding grazing will change things but it also matters how they are managed, as many prairie folks have mentioned before. How much it burned and how frequently will make a huge difference in the effect. If large areas are burned, bison will create camps rather than adhere to a burn patch which can be moved from year to year. Also, bison don’t particularly like legumes so are less effective in controlling introduced legumes than cattle. Nevertheless, it’s better to have something grazing than none. Legumes and other invasives will reinvade but what the mechanism is isn’t easily determined. Sericea leaspedez appears to have moved several hundred yards, maybe more from mice caching seed as from large ungulates or birds.
Nice post Chris. This one hits closer to home. What I would like to know is the delta in average management time (field labor hours) between a typical Platte River prairie and a Nachusa Grassland prairie? I realize this is hard to quantify, but given your field management techniques comparison between the two sites, you must have some rough order of magnitude feel for it?
David – a very hard question. I would guess that Bill’s crew probably spends twice the hours per acre (maybe more) on prairie management than we do. Then, if you do the same comparison between our Platte River Prairies and the Niobrara Valley Preserve (in the sandhills of Nebraska) the NVP crew probably spends 1/5 of the time per acre that we spend along the Platte. Most of those differences between labor needs per site are due to the abundance/aggressiveness of invasive species. Of course, Bill has compensated for that by building a tremendous crew of volunteer stewards who are very independent, knowledgeable, and competent. They do amazing work and accomplish many more times what Bill’s TNC staff could do alone.
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