I’ve said many times that prairie and wetland restoration work has been some of the most gratifying of my career. The opportunity to literally build new prairie from the ground up is pretty tough to beat. Perhaps the only thing better is the chance to watch that new prairie become a mature, dynamic community of plants that supports a broad diversity of animals as well.
I’ll apologize up front that this post might be a little too ‘inside baseball’ for some readers. I’m going to share a lot of details about a restoration project that I think are fascinating. I’m hoping at least a few others will enjoy it, but I won’t be offended (and I won’t know anyway) if some of you skim this pretty quickly and move on. The last three paragraphs summarize the story pretty well if you want to skip ahead.
Last summer, a couple of my favorite restored prairies hit their 20th growing seasons. One of them, the Derr West 2002 Restoration, has been particularly interesting to watch for several reasons. First, it was planted with the most diverse seed mix we’ve ever created – a total of 218 plant species (all locally-harvested). Second, when we started grazing the site, we built a permanent exclosure in one corner that has given us some ability to compare fire only management with fire/grazing management. Finally, and related to the first two, I’ve been collecting intensive plant community data at the site every season since the site’s 3rd growing season in 2004.
Site Description, Management, and Evaluation Methods
The 68 acre former cropfield includes 6,000 linear feet of slough wetlands we created by excavating shallow channels that have standing water when groundwater is high. Spoil from those excavations were used to create curvilinear (there’s a word!) sand ridges. Those wetlands and ridges were planted with tailored seed mixes and the remainder of the site was planted with a mix of mesic plant species that included some of the wet and sandy species too. Seed was broadcast in February, 2002 with an EZ-Flow fertilizer spreader that dropped the seed onto soil that had been disked after corn was harvested the previous fall.
Starting in 2009, we combined this restored prairie with adjacent prairies to make a 370 acre management unit and began a modified patch-burn grazing approach that included a year of complete rest from grazing every once in a while. Within that large management, units were burned (usually either early or late spring) and then intensively grazed for a full growing season. At any one time, there were patches being grazed hard and others that were in the midst of a multiple year recovery period from the last grazing treatment. The exception was a 9 acre grazing exclosure we built at the northwest corner of this restored prairie, which got burned at about the same frequency as the rest of the site (average = 3-4 year frequency), but never grazed.
It’s been fascinating to watch the site mature and evolve. In addition to frequent wandering around the site, I also collected annual data on plant composition. Dating back to 2004, I’ve stomped through the prairie every year with a 1×1 meter plot frame, plopping it down about 70 times in the grazed area and 25-30 times in the ungrazed exclosure (random stratified design – not permanent plots). Each time I laid the frame down, I listed all the plant species I could see within it.
Results
Between 2004 and 2021, I’ve found a cumulative total of 175 different plant species within those plots. I only sample from the mesic portions of the site, (skipping the wetlands and sand ridges) so I feel like 175 species is pretty good. There are probably a few I’ve missed because they aren’t common enough to have show up within those little plots yet (the sum total of all those plots is about 1/5 acre, so I’m sampling a very small portion of the total each year). I also haven’t crosschecked against the initial planting list to see what we planted that isn’t yet on that list, but there can’t be too many absences.
For those of you who might want to dig into the full details of the following results, here’s a link to a PDF so you can peruse at will. For the rest of you, here are a few highlights:
Floristic quality is a metric that combines species richness (# of species) with a rating of how tolerant a species is to degraded conditions. Species found mainly in non-degraded sites get higher values. I averaged the floristic quality of all the 1×1 subplots I sampled from each year to get a mean floristic quality number. If you look at the above graph, mean floristic quality grew during the late establishment phase of the site. You can also see a brief dip in 2013, a year after a severe drought in 2012. Apart from that, there has been little change over time, which I take as a sign of ecological resilience.
The next two graphs show the same time period depicted in the first graph, but include comparisons between the data from the grazed portion of the site and the ungrazed exclosure. The first graph shows mean floristic quality again and the second graph shows mean species richness, which is simply the average number of plant species found within those 1x1m plots each year.
My interpretation of the above graphs is that the seeded plant community has been remarkably resilient over time. Through fire, drought, floods, and grazing (in the grazed area), the community has maintained its diversity. Grazing doesn’t seem to have had a negative impact on floristic quality and has had a positive impact on species richness (number of species per plot) in most years. Some of that higher species richness is due to ‘weedy’ species that benefit from periodically weakened grass dominance, but as the graphs below show, there’s more to the story.
It’s interesting how obvious the effects of the 2012 drought are. Mean floristic quality dropped in both the grazed and ungrazed areas in 2013 but recovered within a year or two. Mean species richness in 2013 dropped in the exclosure (but not in a statistically significant way) but rose strongly in the grazed portion of the site, likely because a broad suite of plants took advantage of lower competition from species stressed by the drought. Both floristic quality and species richness leveled back off quickly, however. Again, I feel like this is positive evidence that this constructed community is able to adapt and withstand stressors.
The following graphs show example species and their individual changes in frequency of occurrence through time. Frequency of occurrence is the % of 1×1 plots the species was found within each year. The orange lines show species occurrence frequency in the grazed area and the dark blue represents the same for the ungrazed exclosure. I find it fascinating to see the differing patterns. I can make informed guesses about the reasons for some of them, but others just raise fun questions that would be fun to explore.
As you look at the graphs, remember that there’s just a single exclosure, it is considerably smaller than the grazed area (9 acres compared to 59 acres) and includes less variation in soil conditions. In addition, there are fewer than half as many samples from the exclosure as from the grazed area. As a result, be cautious in interpreting too much. This isn’t a replicated study, it’s just a comparison to help interpret what’s going on and to trigger questions to follow up on. I focus mostly on the initial difference between occurrence frequency within grazed vs. ungrazed areas in 2009 and whether that difference grew or shrank over time.
I’m really encouraged by the apparent resilience of this site over time. Most species vary in abundance from year to year, but I don’t know of any that have disappeared altogether. The plant communities within the exclosure and grazed areas have become different from each other over time, but neither is necessarily better. The exclosure is less diverse and more grass-dominated, but also has higher abundances of some forb species that seem to thrive better in the absence of grazing (but are surviving in the grazed area as well).
Most importantly to me, the grazed area, which definitely has more heterogeneous habitat (other data not shown here) doesn’t seem to be showing signs of degradation due to the grazing management we use to manage it. Mean floristic quality remains stable and we’re not seeing local extinctions of any plant species. We’re creating a wider range of habitat while still maintaining a diverse plant community.
However, our restoration objective is not just to create a diverse prairie plant community in what used to be crop land. The primary objective is to use that restoration project to enlarge and reconnect neighboring prairies. A diverse plant community contributes toward that, but it’s also important that the new habitat acts as ‘connective tissue’ and provides places for animal species to feed, live, and travel.
We’ve collected data on bees, ants, small mammals, and grasshoppers/katydids that indicate we’re doing well on the habitat front, in addition to maintaining plant diversity. If we can create habitat that helps defragment the landscape, manage it for a diversity of animals, and maintain plant diversity over long periods of time, that’s pretty sweet. We still have a lot to learn, and our oldest sites are still less than 30 years old, so a lot might happen that will make us reconsider, but so far so good!
The Prairie Ecologist 
Congratulations on this great work, and evidence of significant improvement in grassland habitat! Question: you say there’s data on “bees, ants, small mammals, and grasshoppers/katydids”, but no birds? Specific reasons why not included? Decline of grassland birds such a significant issue with many mitigation efforts, like yours?, being undertaken. Be great to know what worked for which species? Thank you.
Hi Deborah, we have looked at birds too, and all the expected species are there. I just think of birds as easy targets to hit. They mainly respond to habitat structure and patch size. Breeding success, of course, is more important than presence/absence but much harder to quantify. We’ve had a couple studies on that too, and cowbird parasitization rates are high, but that’s a landscape issue, not related to this individual restoration patch.
The list of species nesting there includes grasshopper sparrow, western meadowlark, dickcissel, bobolink, upland sandpiper, common yellowthroat, northern bobwhite, and others. Even 1 family of burrowing owls a few years ago
Chris, This is exceptional work, and an amazing restoration story! How many of us are ever able to stay on somewhere and track habitat changes to this degree? We end up changing jobs, and no one completes/continues the plant monitoring that we worked so hard on. A sad and all too common story. Your work is like a dream come true here! Kudos for having the foresight on the planning, and for then seeing it through. To me the results make sense and nice validate that grazing, fire, and drought are all driving the plant community in various ways (like your past analogy of the “deep bench” of a baseball team). Thanks so much for taking the time to tell us the story – and again, congratulations on your diligence through all these years.
Thanks Beth. And thanks for reading it!
Very interesting Chris, though I’m not sure what defragment is.
Does my memory serve me in thinking Derr West had the most ant species of the sites Laura and I sampled? I so wish I’d had more time and another season or two (at least) to watch what happened as the ants colonized and fluctuated as they might.
Just figured out … de-fragment.
I think you’re right about the ants on Derr West. Would you prefer ‘reverse fragmentation’? : )
Nah, we’re good.
Very interesting! My little restoration/reconstruction also showed tall dropseed decrease after grazing stopped…but what I was wondering about was the prairie larkspur. I thought this was toxic to livestock? We had a friend a few miles from us that had Longhorns die from this larkspur. (At least that what the diagnosis was) Curious if that was actually true. Thank you for the great post!
Thanks Bruce. I’m not a veterinarian or plant toxicity expert, so don’t rely much on my information. What I understand, though, is that larkspur is indeed poisonous, and especially dangerous to cattle. However, there are toxicity differences between species and I don’t think ours (Delphinium carolinense) is one of the more dangerous. Regardless, with most toxic plants, the danger occurs when animals ingest large quantities. Often, as long as those species are mixed in with lots of other plants, that risk is pretty low. Milkweeds, for example, I have much more experience with, and it’s pretty hard for a cow to eat enough milkweed to be dangerous unless it’s being mixed at high rates into hay, etc. I’m not saying the same is true for larkspur, however. In the Platte River Prairies, prairie larkspur is a pretty uncommon plant. The patch in the photo is the biggest I’ve seen in years. We’ve had no issues with any cattle toxicity. Again, this is all from an ecologist’s perspective not from a cow’s or a veterinarian’s!
This is awesome, Chris! Thank you! Do you like random plots vs fixed plots? We do fixed. Maybe we should be mixing up the locations of our plots every year?
Joe
Sent from my iPhone
Hi Joe, I think fixed points are terrific, and can reduce your statistical error, so I certainly wouldn’t shy from them. I used random because I didn’t want to have to mark and find a bunch of permanent plots each year, but it means I need more points to see change. I guess having more subplots also means I get a larger sample size for looking at total species richness, etc., but less time collecting data would also be handy!
This is very interesting!
Is there any similar data on prairie thicket species, such as wild plum?
Regards, Dr. Christina Larson
On Mon, Jan 24, 2022 at 5:28 PM The Prairie Ecologist wrote:
> Chris Helzer posted: ” I’ve said many times that prairie and wetland > restoration work has been some of the most gratifying of my career. The > opportunity to literally build new prairie from the ground up is pretty > tough to beat. Perhaps the only thing better is the chance to ” >
Hi Christina,
We definitely have some plum and other shrubs. This particular site doesn’t have much (except for the Siberian elms we’re trying to get rid of) but others do. I’ve evolved on those thickets. When I started as the land steward on the Platte, I worked to remove most of them because I saw them as places that harbored tree invasions (which is true) and we had small fragmented habitats that I didn’t think could stand getting smaller because of habitat loss to shrubs. I saw shrubs on our neighbors’ lands and figured they would cover the landscape needs. Today, I advise our land management staff to find places to allow those thickets because they are valuable habitat and there aren’t many on neighboring lands. However, it’s still a difficult balance between letting them get too big (and allowing trees to grow amongst them) and allowing them to persist and contribute to the overall habitat one the landscape. Adding 1,500 acres of prairie habitat through restoration makes me feel better about shrubs too – we’ve got more space for them than we used to. Anyway, we don’t actively plant them in our restored prairies, but tolerate them as they move in from the edges from nearby remnants.
Excellent! I so enjoy your posts on The Prairie! Okay, so how do we convince the Billionaires and Millionaires who are now so intoxicated w/ the ‘Western ‘ lifestyle, IE: Yellowstone, to buy a ranch, remove the agriculture, and return it to prairie w/ part cattle production for their tax write – off. This needs to get to the NY Times !!!!!
Wow great post!! Love to see these time series.
Question:
Are there practical books on building wetlands?
I am on the top of the watershed for a side branch of Strawberry Creek in Central Alberta (Aspen Parkland eco zone, so Prairie-ish, depending on what stage of the fire cycle a given patch is.)
When I bought the land, most of it was sharecropped to a neighbour. The 30 inch culvert under the road ran half full for 3 days, and that was our stream for the year. Ephemeral stream indeed.
I’ve let the land go wild after an initial dose of pasture mix. Now it is a fascinating mix of pasture, some invasives, and colonizations. This is probably not the best way to recreate a prairie, but it is cheap and it’s diverse.
Curiously, being ungrazed by livestock,at least two of the invasives, tansy and orange hawkweed, do not spread fast. I have to do some cleanup next spring, but tansy has gone from 3 plants to about 20 in 20 years. My suspicion is that a lot of these invaisives need the disturbance and sunlight created by heavy grazing.
***
Back to my question: Right now I have an 800 cubic meter pond , and upstream from it, I’ve used dead trees and empyting pots from my tree farm to build a 2 foot high dam across the channel. It leaks, but acts as a filter for the pot. It holds water at the height of the spillway for about 6 weeks, and becomes a wet spot by late summer.
I would like to build a chain of ponds up the watercourse, but haven’t found a guide in how to do it right. Any pointers to “The Dummies Guide to Buiilding Wetlands?”
Factoids:
* Typical precip of 16-20″ total per year, about 1/3 of that coming down as snow.
* From the culvert upstream there is about 120-160 acres of water shed. Of that about 35 is in poplar bush/willow, most of the rest is in either my pasture/prairie, or my neighbours pasture. Neighbour does one crop of oats every 3 years, and bales it green to keep for winter feed for 20 cows.
* The province defines ephemeral stream as one having clear stream banks. The banks on most of my stream are a terrifying 3″ tall
Wetlands are not my strong suit. Here, we can create wetlands just by digging closer to groundwater, which I can manage. When it comes to flowing water, I’m out of my depths. Plus, you’ll probably want local expertise to deal with conditions and lessons learned from Central Alberta. I’ll think about anyone I know or resources, but I don’t have many wetland contacts, as opposed to prairie folks. Good luck! Sounds like a great and worthwhile project.
This is so cool! I’ve been staring at these graphs all morning when I should have been doing a school assignment. Oops :)
I really love your updates! I found you through the wildflowers book (of course!) but I love being a subscriber, thanks! ᐧ
On Mon, Jan 24, 2022 at 3:29 PM The Prairie Ecologist wrote:
> Chris Helzer posted: ” I’ve said many times that prairie and wetland > restoration work has been some of the most gratifying of my career. The > opportunity to literally build new prairie from the ground up is pretty > tough to beat. Perhaps the only thing better is the chance to ” >
This is awesome, Chris! Thank you! Do you like random plots vs fixed plots? We do fixed. Maybe we should be mixing up the locations of our plots every year?
Joe
So not to rain on this parade, but kind of: 1) Your grazing exclosure is only in the bottom, and the grazed area includes both bottomland (still upland) and sand hill habitat. 2)FQI is area dependent as is richness because richness is in the calculation, so better to present mean C and richness both alongside it when presenting FQI rather than just richness (especially when they are pointing in opposite directions, which raises questions about why just one would be presented). 3) In order for FQI to be so low in grazed and ungrazed at that level of meter square richness (~6-12), mean C generally has to be very low to get those values, and given that FQI is similar or nominally higher in the exclosure and richness is lower, a mean C difference must be taking up the slack…but it’s low across the board. Even in a rich planting, outcomes are constrained by what goes in. There were only two conservative species in the mix (none present as of last year). So, no, you aren’t seeing extinctions of any plant species, but you also didn’t really get any going. I think it’s possible that you’d have similar floristics if you hadn’t seeded at all and simply left it fallow and started grazing as you did.
Dan, I’m not going to force any interpretations on you. That’s totally up to you. I will clarify a few things. 1. There aren’t hills here other than a few linear sandridges that aren’t included in the sampling area. So there’s no elevation difference between the exclosure the rest of the site – it’s all in the same flat alluvial floodplain and part of the same former crop field. As I acknowledge in the post and PDF, though, the exclosure small and doesn’t cover the same area or range of alluvial soil variation. All fair. 2. Not sure what you mean here about FQI being area dependent. FQI is calculated for each of the square meters and then averaged across all those 1×1 plots each year. Range of variability is accounted for by the confidence intervals. 3. I’d be interested to hear what conservative species you think are missing from our mix that are present/appropriate for the Platte River valley. What do you think we’re missing? Our seed harvest list includes just about every species I know of that’s part of these mesic prairies along the Platte, based on a composite of reference sites here, as well as along other similar alluvial plains in Nebraska. There aren’t a lot of plant species ranked higher than 6 in those prairie systems (not because they’re degraded but because those community types don’t have a lot of species that were assigned higher C-values). Comparing FQI values between places is really tricky – botanists that assign values are necessarily using some subjectivity in that process and it’s a relative process, not an absolute one. Some of the species that are 5’s and 6’s here would be 7’s or 8’s in Missouri or elsewhere (purple prairie clover, as one example). Anyway, as I said, you’re more than welcome to interpret these results as you like – it’s why I laid them all out. However, I would definitely push back against your claim about getting similar results from simply letting the field go fallow. That’s simply not the case and there is ample evidence of that.
Chris, I’m a fan of all of your posts, but this is my favorite in years. Thank you for taking the time to do this long-term study and to write it up for the rest of us to learn from! There is the school of thought that to get conservative plants going in a restoration, the soil has to be prepared by less conservative plants first. I’m sure that’s true for conservatives that have strong relationships with certain soil microbes, but in my area, it’s not unheard of to see the 9s and 10s on the index of conservatism growing on man-made pond dams and badly eroded slopes. For plants that are not highly dependent on specific soil microbes, it makes me wonder if a lot of the long term advantage goes to whatever can establish itself on a piece of ground first and get a foothold, regardless of its position on the index. Does your study shed any insights on this? Possibly through the relative abundances of the most conservative plants over time?
Hi Ian, and thanks. I don’t know that I subscribe to that theory. There are good examples (Nachusa Grasslands in Illinois, for example) where they’re getting some very conservative plant species in their initial establishments. I’m not saying it doesn’t apply to some species, but I don’t get the impression that it applies to MOST 9’s and 10’s. (Also, see my response to prairiebotanist about the lack of prairie species in our part of the state that are assigned 9’s and 10’s) But to answer your last questions – no, I don’t think this particular project sheds any light on the question. If I remember correctly, though, the idea of successional restoration (restoring in waves, starting with ‘pioneer species’ and then adding others later has fallen out of favor in Midwestern States where it was initially tested. I don’t know that the approach is a failure, but there are lots of examples of very diverse prairies (with conservative plants) being established from a strong initial seed mix.
Very enjoyable and thorough read, Chris. What an excellent body of work! My question is, do you find neighbors who are asking for and adopting grazing regimes like yours, along with overseeding with more species to enhance diversity? I guess I wonder whether this type of restoration is really only going to happen on dedicated conservation lands. This seems to me the next important story to tell.
Hi Patrick, and thanks. I’d say the news is mixed. The work that we and others like Prairie Plains Resource Institute have done to showcase these restoration techniques has definitely had impacts. PPRI has planted well over 10,000 acres of this kind of restoration across eastern Nebraska. That’s significant, though still far from sufficient, of course. We’ve also influenced the practices encouraged and cost-shared by other groups like the Natural Resources Conservation Service, Nebraska Game and Parks Commission, and Pheasants Forever, which has helped this restoration practice spread further as well. That spread is still pretty limited, though, by limits in the availability of these diverse mixes commercially, and even more by the financial issues associated with converting profitable cropland to prairie. My hope is that we (society) will begin prioritizing restoration of strategic gaps between and around existing remnant prairies that will enhance their resilience and population viability. We don’t have to (and shouldn’t) restore all of eastern Nebraska, but we could fill some critical spaces in ways that would make a huge difference.
In terms of the fire/grazing work, that is gaining traction and changing perspectives on what habitat on ranches can look like. UNL is starting a big collaborative study on patch-burn grazing in the Sandhills – not with the goal of exporting patch-burn grazing, per se, but to investigate and demonstrate what a more heterogeneity-focused management approach can look like in that landscape. It’s a project that includes ranchers, along with scientists, and I’m optimistic that the results will have a big influence on habitat management by ranchers in the Sandhills and beyond.
So – progress, but still lots of work to do.
Thanks Chris. I needed to hear that today. I think if we can get that message out more broadly and framed correctly, and adequately resource and sustain these efforts, then progress has a chance to snowball. I for one am interested in hearing more of those stories.
Thanks for the information Chris. The increase in Smooth brome & bluegrass really stuck out to me. That’s good the invasive grasses aren’t causing a decrease in diversity, but how concerned are you with there continued upward trend?
Hi Chris. I’ve been reading your book – the ecology and management of prairies. I’ve been doing a project for the Prairie Project for the last 2 years with goats and my high school classes. I present at the SRM meeting in a couple weeks. Are you attending? I have data I have collected… but I’m trying to figure out the best way to do present it. Would you be interested in looking at it with me? Understand High school kids collected it. Also I’m trying to decide what the next step should be in management of my small area. Zoom or google classroom. Thanks Shannon Chatwin 918-408-5808
On Mon, Jan 24, 2022 at 5:27 PM The Prairie Ecologist wrote:
> Chris Helzer posted: ” I’ve said many times that prairie and wetland > restoration work has been some of the most gratifying of my career. The > opportunity to literally build new prairie from the ground up is pretty > tough to beat. Perhaps the only thing better is the chance to ” >
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