A Milestone for Prairie Restoration

Because conservation work can sometimes seem like blowing into the wind, it’s important to pause periodically to celebrate progress.  For example, I am really excited about what has been accomplished in the field of prairie restoration.  We’ve known for a while that we can convert cropland to prairie vegetation with a high diversity of plant species (150 or more species per planting), and that we can do that on a scale of thousands of acres.  The Nature Conservancy has large projects in states like Indiana, Illinois, and Minnesota where restored prairie landscapes now range from about 5,000 to 20,000 acres in size.  The U.S. Forest Service is transforming an old U.S. Army Arsenal into 20,000 acres of prairie in Illinois.  Prairie Plains Resource Institute, the organization that pioneered restoration techniques in Nebraska, is planting up to 1000 acres a year now and has established well over 10,000 acres total across the state.

Our staff celebrates a successful year of seed harvest back in 2015.
Our staff celebrates a successful year of seed harvest back in 2015.

Here in our Platte River Prairies, we’ve restored more than 1,500 acres of cropland to prairie.  That’s not insignificant, but more importantly, we’ve been testing the idea that those restored prairies can help defragment the ecological landscape around them.  Habitat fragmentation is one of the largest threats to today’s prairies because it shrinks and isolates populations of species, making them vulnerable to becoming locally extinct without the chance of recolonization from nearby sites.  The real promise of prairie restoration is that it can enlarge and reconnect scattered remnants of native prairie, providing populations of animals and plants a much better opportunity to survive and thrive.  It’s not feasible or desirable to convert the majority of cropland in the central North America back to prairie, but there are particular sites where strategic restoration work could make a huge difference in the potential survival of prairie species and ecological services.

In order for prairie restoration to help defragment landscapes, restored prairies have to provide suitable habitat for the species living in small isolated prairies.  Many bees and other insects specialize on certain plant species, for example, and other animals rely upon an abundance of prey, a diversity of seeds, or other particular food or habitat conditions.  Satisfying the individual needs of all those prairie animals is a critical measure of success if prairie restoration is going to successfully stitch isolated prairies back together.

Over the last several years, we’ve been collecting data to see whether the species of bees, small mammals, grasshoppers, and ants in our unplowed prairie remnants have moved into adjacent restored habitat.  The results have been very positive.  While not every species of animal living in our remnant prairies has been found in nearby restored habitat, we’ve found the vast majority of those we’ve looked for.  We suspect that most of the remaining species are also present but that our limited sampling effort just hasn’t yet picked them up.  We’ll keep trying.

Dillon Blankenship, a Hubbard Fellow, compared grasshopper, katydid, and tree cricket communities on three pairs of remnant/restored prairies back in 2014. Almost all species were present in both restored and remnant habitats. In the three species that weren't, only one or a very few individuals were found, so it's likely just a sample size issue.
Dillon Blankenship, a Hubbard Fellow, sampled grasshopper, katydid, and tree cricket communities on three pairs of remnant/restored prairies back in 2014. Almost all species were present in both restored and remnant habitats. In the three species that weren’t, only one or a very few individuals were found, so it’s likely just a sample size issue.
Data from James Trager and Kristine Nemec has helped us compare ant species composition in restored versus restored prairies along the Platte River. So far, we've documented 30 species and only one has been found exclusively in remnant prairie (and, again, it's likely to be a sample size issue).
Data from James Trager and Kristine Nemec has helped us compare ant species composition in restored versus restored prairies along the Platte River. So far, we’ve documented 30 species and only one has been found exclusively in remnant prairie (and, again, it’s likely to be a sample size issue).
Master Naturalist Mike Schrad and Hubbard Fellow Jasmine Cutter have both helped us compare small mammal populations between restored and remnant prairies. This table shows some of Jasmine's data from one site. In general, we're finding that the same species are in both restored and remnant prairies, but the relative abundance of those species is often different - with some apparently favoring remnant habitat and others favoring restored areas.
Master Naturalist Mike Schrad and Hubbard Fellow Jasmine Cutter have both helped us compare small mammal populations between restored and remnant prairies. This table is from Jasmine’s data from one site, showing the number of trapsites in which each mammal species was caught back in 2014. In general, we’re finding that the same species are in both restored and remnant prairies, but the relative abundance of those species is often different – with some apparently favoring remnant habitat and others favoring restored areas.  We’re now looking at how our management affects presence and abundance of each species through time.
We've had several research projects look at native bees in our prairies. Mike Arduser, Anne Stine (Hubbard Fellow), Bethany Teeter, and Shelly Wiggam Rickets have all helped us compare restored and remnant prairies. So far, we've found over 72 species and the vast majority have been in both remnant and restored prairie.
We’ve had several research projects look at native bees in our prairies. Mike Arduser, Anne Stine (Hubbard Fellow), Bethany Teeters, and Shelly Wiggam Rickets have all helped us compare restored and remnant prairies. So far, we’ve found over 72 species and the vast majority have been in both remnant and restored prairie.
I've collected more than 15 years of data showing that plant diversity and the frequency of occurrence of prairie plant species has remained stable through time. These four graphs show four species in one restored prairie where we're comparing fire/grazing management to fire only management.
I’ve collected more than 15 years of data showing that plant diversity and the frequency of occurrence of prairie plant species has remained stable through time. These four graphs show four species in one restored prairie where we’re comparing fire/grazing management to fire only management.  The long-term persistence of prairie plants and diverse plant communities is critically important for plant communities, but also for the success of efforts to defragment habitat for animals.

These results mean that where prairie landscapes have been largely converted to row crops, we don’t have to just watch while insect or small mammal populations careen toward local extinction in tiny isolated prairies.  We’ve shown that we can make those prairies larger and more connected, and that animal populations can grow and use new restored habitat and diverse plant communities.  We’ve also shown that restored prairies can sustain their biological diversity for decades, even through periods of intensive grazing and drought.  While there are still plenty of questions and potential improvements we can make, we’re now at the point where society needs to decide whether and where to do this kind of restoration.

I don’t know about you, but I think that’s pretty exciting!

Nebraska and other states in central North America have large swaths of productive and important cropland.  As I said earlier, I’m not advocating that we convert most of that back to prairie.  However, there are specific sites where row crop agriculture is marginally productive/profitable and the long-term interests of both society and local landowners might be best served by putting land back into diverse and productive grassland.  Agricultural policies and subsidy programs will obviously play a huge role in this kind of strategic large-scale restoration, and getting the policies in place to facilitate this kind of common sense restoration will be plenty difficult.  That’s nothing new, however.  What’s new is our confidence that if we can implement targeted restoration work, it can make a real difference to prairie conservation.

Restoring the viability of prairies in fragmented landscapes is critically important to prairie conservation success.  The challenges of conserving species in small isolated prairies are immense, and many of those prairies will continue to see declines in biological diversity and ecological function over time unless we can make them bigger and more connected with other prairies.  Helping to document our ability to do that – at least for many prairie species – has been one of the most satisfying things I’ve done during my career.

 

Important footnote:  Restored prairies are not the same as remnant unplowed prairies.  Soil organic matter levels, for example, can take many decades to recover from tillage, and relationships between plant and microbial communities may take just as long to become reestablished.  Our success in prairie restoration should definitely not be used as justification for plowing up remnant prairie!  However, it’s equally true that prairie restoration efforts aren’t failures just because they can’t create an exact replica of prairie as it existed before it was converted to farmland.  If defragmenting prairie landscapes is the primary goal of restoration, we just need to create restored prairies that complement – not copy – remnant prairies. 

 

Register Now – 2016 Grassland Restoration Network Workshop

It is time to register for the Grassland Restoration Network’s 2016 workshop.  The Grassland Restoration Network has helped people working on prairie restoration share techniques and conservation strategies since 2003.  You can read my blog post from last year’s workshop in Minnesota here and from the 2014 workshop at The Nature Conservancy’s Nachusa Grasslands in Illinois here.

One of the best ways to learn from each other is to visit each others' projects and evaluate them together. 2015 Grassland Restoration Network workshop - Minnesota.
One of the best ways to learn from each other is to visit each others’ projects and evaluate them together. 2015 Grassland Restoration Network workshop – Minnesota.

The 2016 workshop will be September 13-14 right here in Nebraska.  It is co-hosted by The Nature Conservancy’s Platte River Prairies and Prairie Plains Resource Institute.  You can see the agenda and other information for the workshop here.

Registration for the workshop is open now through August 19.  There is no registration fee for the first 75 people to register, but you’ll be responsible for your own transportation and lodging, and some meals.  To register, send an email to Mardell Jasnowski at mjasnowski(at)tnc.org.  Include answers to the following questions:

Name

Organization/Affiliation

Address

Phone Number

Email Address

Will you take part in the optional Tuesday morning tour in Aurora?

Will you be eating Tuesday evening supper?

Will you be eating Wednesday lunch?

Do you have any dietary restrictions?  If so, list them here:

Thank you to Pheasants Forever and the Nebraska Environmental Trust for helping to cover the costs of registration for this conference.

 

Chuck Norris of the Prairie

A big topic of conversation at this year’s Grassland Restoration Network (GRN) workshop had to do with designing seed mixes to combat potential invasive plant problems.  When converting cropland to prairie vegetation, the first few years of establishment are sometimes a race for dominance between prairie plants and invasives.  Once a strong native plant community becomes established, it is more difficult (but still possible) for invasive plants to become dominant, so those first few seasons are critically important.  Over the years, a number of people have tried using extra high seeding rates of various native plants to see if those natives could help stave off invaders.  In an ideal scenario, a high abundance of some showy wildflower would outcompete invasive plants but allow other native plants to establish.  Nice, right?  Lots of pretty flowers during establishment, no invasive species to worry about, and a nice diverse prairie community in the long run.

Black-eyed susans (Rudbeckia hirta) in restored prairie - TNC Platte River Prairies, Nebraska.
Black-eyed Susan is a species that has shown some promise as a species that can compete against invasives but still allow the establishment of a diverse plant community around it.   The Nature Conservancy’s Platte River Prairies, Nebraska.

I first heard about this idea at the 2004 North American Prairie Conference.  In one of my favorite presentations of all time, Shawn Schottler of the Science Museum of Minnesota compared various plant species to celebrities.  As he described his experiments, he said he was trying to find Chuck Norris plants (tough good guys) that could fight off Mike Tysons (aggressive invasives) while still allowing Patsy Clines (less competitive natives) to establish.  As I recall, he was having some luck with Chuck Norris species such as black-eyed Susan (Rudbeckia hirta), wild bergamot (Monarda fistulosa), and others.  At this year’s GRN workshop, Jack Norland of North Dakota State University described recent results of some similar experiments on U.S. Fish and Wildlife restoration projects.  The “spike” treatments they used consisted of ultra high seeding rates of species such as plains coreopsis (Coreopsis tinctoria), purple prairie clover (Dalea purpurea), Canada wild rye (Elymus canadensis), and others.  His data showed Canada thistle to be much less abundant in spike treatments than in the controls.

Interestingly, we’ve had some accidental experience with this topic here in our Nebraska Platte River Prairies.  During the drought years of the early 2000’s, some of our prairie plantings ended up with lots and lots of Canada wild rye.  In some cases, the species was so abundant that our plantings looked like wild rye monocultures.  We weren’t the only ones.  Prairie Plains Resource Institute had plantings that looked much the same during those years.  There was some hand wringing about whether or not the plantings had failed, especially given the drought conditions at the time, but Bill Whitney of Prairie Plains assured us that it wasn’t a big deal.  He was right, as usual.  The plantings eventually emerged from their wild rye phase and turned into very nice prairies.  In fact, our site that had the “worst” wild rye infestation is now the showiest (in terms of big colorful wildflowers) prairie we have.  I’m not sure the wild rye helped suppress any invasive species, but a high density of wild rye plants didn’t seem to keep Patsy Clines from eventually thriving.

This 2004 shows one of our Platte River prairie plantings in its third year of growth.  Canada wildrye is visually dominant, but other species are present as well.
This 2004 photo shows one of our Platte River prairie plantings in its third year of growth. Canada wild rye is visually dominant, but other species are present beneath its canopy.  Many of our young plantings from about that time period looked much like this for several years in a row.
After this prairie was seeded in 2000, it was a near monoculture of Canada wild rye for several years but today is our showiest wildflower patch.
After this prairie was seeded in 2000, it was a near monoculture of Canada wild rye for several years.  Today it is among our most diverse prairies and showcases our showiest wildflower patches.  (July 2015 photo)

Spike treatments/Chuck Norris species/etc., are really just variations on the idea of using a cover crop – planting something intended to establish early and then fade away (mostly or completely) as the desired vegetation takes hold.  In some places, cover crops are very useful in agricultural systems as a way to prevent soil erosion and loss of fertility, suppress weeds, and/or preserve soil moisture.  It seems logical that they would also help with prairie restoration establishment.  In fact, I recently talked to someone with the Natural Resources Conservation Service (NRCS) in north central Nebraska who says their best successes in restoring sandhill prairie come when they use a cover crop of millet.

On the other hand, I remember a GRN workshop about five or six years ago when we had a group discussion about our experiences with various cover crops.  Participants from across the Central U.S. seemed to reach consensus that cover crops were as likely to be counterproductive as helpful to prairie restoration efforts.  This seems to conflict with the successes seen by people like Shawn Schottler, Jack Norland, and others.  Why the differences?

Part of the issue is certainly that we’re still experimenting with different species, and still have a lot to learn.  Beyond that, though, anyone who has spent many years restoring prairie knows that establishment results can be very difficult to predict, even within the same site.  Just when you think you’ve got something figured out, your next planting turns out completely unlike what you’d expected.  Those kinds of inconsistencies, combined with differences in site attributes such as soil texture and fertility, rainfall, and latitude make it almost impossible to come up with restoration recommendations that apply everywhere.  In fact, if we’ve learned anything through the Grassland Restoration Network, it’s that it’s important to start big projects by doing some small experimental plantings to see what works best in that place before investing in larger scale work.

Grassland Restoration Network Meeting.  Hosted by TNC Minnesota.
There is great value in getting a bunch of restoration practitioners together in one place.  We often bring home new ideas to try.  Sometimes they even work.  2015 Grassland Restoration Network workshop – Minnesota.

Clearly, the idea of “spike” treatments and similar strategies hold a great deal of promise if they fulfill their promise of preventing invasives while facilitating establishment of diverse plant communities.  However, since it’s also clear that successful strategies from one site don’t always translate well to others, we may each have to find our own formula for success.  Hearing about Dr. Norland’ experiments in the Dakotas has inspired us to do some more experimentation here.  Maybe we can find a few Chuck Norris species to keep the peace in our Platte River Prairies.

If you’ve had positive or negative experiences with cover crops in prairie restoration, or have found your own Chuck Norris of the prairie, please share what you’ve learned in the comments section below.  Thanks.

P.S.  You may have seen or heard some of the many Chuck Norris jokes out there that play on the idea that he is seemingly invincible.  My 14-year-old son likes to share them with me now and then.  A few of my favorites are:

Chuck Norris doesn’t wear a watch. He decides what time it is.

Chuck Norris makes onions cry.

There used to be a street named after Chuck Norris, but it was changed because no one crosses Chuck Norris.

When Chuck Norris does a push up, he isn’t lifting himself up, he’s pushing the Earth down.

A bulletproof vest wears Chuck Norris for protection.

Our New Mechanical Seed Harvester

Seed harvest is a big part of our work here at the Platte River Prairies.  We don’t do as much complete restoration (converting cropland to high-diversity prairie) as we used to because we’ve just about run out of land to restore.  Instead we’ve shifted most of our seed work toward overseeding degraded remnant prairies that are missing many prominent wildflower species.  As a result, instead of harvesting from 230 plant species a year, we’re mainly focusing on getting as much seed as possible from about 30 to 40 species.

Nelson Winkel harvests Maximilian sunflower seeds by hand.
Nelson Winkel harvests Maximilian sunflower seeds by hand.

Most of our seed harvest is by hand, and when needed, we’ve been able to get adequate seed for up to 200 acres of cropland conversion work per year that way.  We’ve also used mechanical means to supplement our hand harvesting, including a couple different combines we’ve owned and pull-behind seed strippers we’ve borrowed from partners.  The mechanical harvesters have been helpful for getting big patches of seed from some grasses, sedges, and a few forbs.  However, the combines we’ve used aren’t very flexible about where they can go (hills and wet areas are tough) and the seed strippers’ brushes haven’t been aggressive enough to remove seed heads of some of the species we really wanted big quantities of – especially for our overseeding work.  However, a recent grant from the Nebraska Environmental Trust, via the Nebraska Game and Parks Commission, made it possible for us to purchase a new mechanical seed harvester.

Here, Nelson is harvesting grass seed with a mechanical seed stripper borrowed from Prairie Plains Resource Institute.
Here, Nelson is harvesting grass seed with a mechanical seed stripper borrowed from Prairie Plains Resource Institute.

After exploring a number of options, we decided to buy a seed stripper from Ned Groelz at Graywind Industries, Inc.  Our friends at Prairie Plains Resource Institute bought a pull-behind stripper built by Ned many years ago, and we liked a lot of its features – especially the ability to remotely control the harvester’s brush on the fly (turning it off and on and adjusting its height while driving through the prairie).  When we ordered our machine, we told Ned we were hoping to harvest large amounts of seed from plants with tough-to-remove seedheads and we weren’t sure a brush would be able to handle those.  He said he’d play with some ideas and see what he could do about that.

When Ned delivered the machine to us, he had a big grin on his face – a sure sign that he’d come up with something for our tough-to-harvest seed problem.  His solution was to replace the harvester’s brush with a more aggressive tool that included “stripping elements” – metal fingers, essentially –  made by the Shelbourne Reynolds company.  (Shelbourne Reynolds sells an attachment for combines that strips, rather than cuts, the grain from crops such as wheat and rice.)  Ned adapted their design for use in his pull-behind seed stripper and he was dying to know whether it would actually work.  Just to be safe, he designed the machine so that we could easily remove his experimental portion and replace it with a tried-and-true brush if we wanted to.

A close-up of the Shelbourne stripper elements included in Ned's new harvester design.
A close-up of the Shelbourne stripper elements included in Ned’s new harvester design.

Ned was so interested in testing his new design, he came out a couple weeks ago to watch it in action.  Without going into a lot of details, let me just say – it works great!  So far, we’ve tested it on wild bergamot (Monarda fistulosa), stiff sunflower (Helianthus pauciflorus), and Illinois bundleflower (Desmanthus illinoiensis), as well as a few others.

The
Nelson and Ned watch the new stripper as it harvests seed from Illinois bundleflower.  The machine is offset from the UTV so the UTV doesn’t smash the vegetation down before it is harvested.
The stripper removes some stems and leaves, as well as seed pods, but leaves most of the plant behind.
The stripper removes some stems and leaves, as well as seed pods, but leaves most of each plant behind.
Ned and Nelson evaluate the performance of the new machine and talk about ideas for further improvements.
Ned and Nelson evaluate the performance of the new machine and talk about ideas for further improvements.

Hand-harvesting will still be an important component of our prairie restoration work. Many plant species are scattered here and there across a prairie and hand-harvesting is the only feasible way to obtain their seeds.  However, other plants occur in big patches, and this new machine is going to let us quickly harvest large quantities of seed from those, which will be a tremendous boon to our overseeding efforts.  We’ll need to do a little more seed processing (using hammermills and screens to separate seeds from the pods, stems, and leaves picked up by the stripper) than with hand-harvested seed, but that should go pretty quickly.

One of my favorite aspects of prairie restoration is the innovation displayed by people trying to come up with new effective ways to harvest seeds.  This new mechanical stripper is one more addition to a long list of those innovations.  Keep ’em coming, folks!

For more information and pricing of Ned’s mechanical seed harvesters, contact him at:

Ned Groelz – Graywind Enterprises, Inc.

2927 W 700 S
Syracuse, UT 84075-9764
Mobile: 801-803-0412
E-mail ngroelz@gmail.com

I want to be perfectly clear -this post was not sponsored by Graywind Enterprises, and we paid full price for the seed stripper and its components.   All the opinions about this equipment and how it worked are just my opinions.  My intent is to let others know of the existence of this machine in case it can help move prairie restoration and conservation work forward.

 

Ten Thousand Acres

A major milestone was reached in prairie conservation today when our good friends and partners over at Prairie Plains Resource Institute (PPRI) planted their 10,000th acre of prairie.

Ten thousand acres of new prairie in Nebraska!  It’s an incredible contribution to our state, and to conservation in general.

Bill Whitney (co-founder and executive director of PPRI) has been a major influence on my career and the careers of many of us in grassland conservation.  He is the godfather of prairie restoration in Nebraska, and personally mentored me in both prairie ecology and restoration during my early years as a young land steward.  If you’re not familiar with Prairie Plains, please click HERE to read more about today’s milestone and all their other accomplishments.

Congratulations and THANK YOU to Bill, Jan, Mike, Sarah, Amy, and Jeff (along with all the other PPRI staff through the years).

Bill Whitney, co-founder and executive director of Prairie Plains Resource Institute harvesting native grass seeds.
Bill Whitney, co-founder and executive director of Prairie Plains Resource Institute harvesting native grass seeds.

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 To put Prairie Plains’ 10,000 acres of restored prairie in context, consider these statistics.

– In 1978, there was an estimated 2,300 acres of high quality prairie left in the entire state of Illinois.

– There are an estimated 12,000 acres of prairie left in Wisconsin today.

– Iowa has less than 30,000 acres of its original tallgrass prairie left.

Assessing Prairie Restoration Through the Eyes of Small Mammals – Part 1

We’ve taken another step in the right direction…

Over the last several years, we’ve begun to evaluate our prairie restoration work beyond just looking at plant communities.  Our primary objective for restoration is to functionally enlarge and reconnect fragmented remnant (unplowed) prairies by restoring the land parcels around and between them.   (See more on that topic here.)  Because of that, it’s pretty important that we look at whether or not species – plant and animal – living in those remnant prairies are actually using and moving through our restored prairies.   In 2012, we brought James Trager and Mike Arduser to our Platte River Prairies to help us start measuring our success in terms of ants and bees, respectively.  We’re still early in that effort, but things look good for both so far.  Most ant and bee species living in our prairie remnants are also showing up in nearby restored prairies.

A deer mouse peers out of the thatch.
A deer mouse peers out of the thatch.

Now we’re hoping to find similar patterns with small mammals.  Mike Schrad, a Nebraska Master Naturalist, has volunteered to help us see whether the small mammal species in our remnant prairies are also in adjacent restored prairies.  We’ve begun by looking at a single 200 acre prairie complex that consists of a remnant prairie surrounded by several restored prairies (former crop fields seeded with 150 or more plant species back in the mid-1990’s).  Mike came out for three nighttime sampling periods in 2013 to see what he could catch in the remnant prairie and one of the adjacent restored prairies.

Mike and I have been looking over the data from this first year, and I’m pretty encouraged by what he’s found so far.  He caught four species in the remnant prairie, and all four were also in the adjacent restored prairie.  In addition, a fifth species, the short-tailed shrew, was caught only in the restored area – but only once.  The five mammal species he caught were:

Prairie vole (Microtus ochrogaster)

Meadow vole (Microtus pennsylvanicus)

Harvest mouse (Reithrodontomys sp.)

Deer mouse (Peromyscus maniculatus)

Short-tailed shrew (Blarina hylophaga)

The relative abundance data for each species caught by site are interesting (see the table below), and reflect the fact that the sites had been largely rested from fire and grazing during the last couple of years.  Voles are attracted to the kind of thatchy grassland habitat found in ungrazed/unburned prairie, and they were caught more often than any other species in our site.  The higher numbers of voles in the remnant prairie might indicate a more dense vegetation structure there than in the restored prairie (or might have just been happenstance).  It was also interesting to see more harvest mice caught in the restored prairie, though the total numbers were low enough that we aren’t drawing any strong conclusions from them.  The total number of animals caught by species and site are below:

2013 Data

On the one hand, seeing the same species in both remnant and restored prairie might not seem very surprising.  Our restored prairies have the same plant species in them as the remnant prairies, and are managed the same way.  It seems likely that small mammals can find everything they need for food and shelter there.  On the other hand, it’s dangerous to blindly assume that we’re providing for the needs of all species when we restore prairies.  The mouse and vole species we saw this year have been pretty well studied, but we still don’t know everything about what they need to survive.  What looks like two identical habitats to us might be very different to a 2 inch tall little critter.  For those reasons, it’s nice to see some support for our assumptions – though we still need much more data.

Mike Schrad records data from one of his trapping efforts.  Mike is a Nebraska Master Naturalist, one of many volunteers being deployed around the state to help with conservation and science projects.
Mike Schrad records data from one of his trapping efforts. Mike is a Nebraska Master Naturalist, one of many volunteers being deployed around the state to help with conservation and science projects.

Over the next month or two, Mike and I will be planning future sampling efforts.  Ideally, we’ll repeat the same kind of trapping he did in 2013, but do so at other sites were we have adjacent remnant and restored prairies.  If we continue to see the same pattern of use – the species in the remnant prairie also using adjacent restored prairie – I’ll start to feel even better about our ability to defragment prairies from a small mammals’ perspective.

However, even if we continue to see results similar to this year, there will be more to learn.  First, there are several less common species of small mammals in our prairies (we think) that weren’t caught this year.  Two of those are plains pocket mouse and plains harvest mouse, both of which could be in our upland areas and are priority conservation species in Nebraska.  Another is Franklin’s ground squirrel, a species we see periodically in our lowlands, but which has disappeared from most tallgrass prairies in the eastern U.S.  I’d like to know that we’re creating habitat for those less common species, as well as for the common ones we caught this year.

There is still a lot to learn about how well our restored prairies are working.  However, with each step we take, I feel a little better about our ability to reduce the impacts of habitat fragmentation by restoring strategic parcels around and between prairie fragments.  Knowing we can do it doesn’t make it economically or socially feasible, but those other factors are irrelevant if we can’t solve the technical issues first – and prove that we’ve done so.

One step at a time…

Report from the 2013 Grassland Restoration Network Workshop – Part 1

The Grassland Restoration Network’s annual workshop took place a couple weeks ago in Columbia, Missouri.  This year’s workshop was hosted by the Missouri Department of Conservation and included more than 90 people from around the country.  As always, the meeting was a mixture of presentations, discussions, and field tours, and was informal enough that we had plenty of time to get to know each other and catch up on what everyone has been learning at their own sites.  There were too many topics and discussions from the workshop to cover in a single blog post, so I’ll spread them out over the next several weeks or months.

Attendees of the Grassland Restoration Network's annual workshop at Tucker Prairie, east of Columbia, Missouri.
Attendees of the Grassland Restoration Network’s annual workshop at Tucker Prairie, east of Columbia, Missouri.

One of the most intriguing discussions of the workshop was an extended conversation during our field trip to the 711 acre Prairie Fork Conservation Area, managed by Missouri Department of Conservation (MDC).  At several points during the trip, we talked about objectives for restoration projects and prairie plantings.  Here in the Platte River Prairies, our restoration objective is to use prairie plantings to enlarge and reconnect fragmented remnant prairies – hoping to increase overall ecological resilience and the viability of populations of plants, bees, etc.  At Prairie Fork, however, there are no remnant prairies to stitch together, and education is a major focus of their restoration project.  Their stated restoration goal is simply to rebuild natural communities and their processes.  Then they use those restored areas as platforms for their education work.

Although Prairie Fork Conservation Area is not far from Tucker Prairie – the last remnant of the once vast Grand Prairie that stretched across a large swath of Missouri – MDC staff are not trying to design their plantings to mimic Tucker Prairie.  Instead, they are harvesting seed from Tucker prairie and other small scattered areas of native prairie vegetation to create seed mixtures that are a composite of all of those sites.  As a result, prairie plantings are allowed to develop into communities as local site conditions allow – a very sensible approach.

Rattlesnake master is common at Tucker Prairie, the last sizeable remnant of the Grand Prairie that used to cover a large portion of northern Missouri.
Rattlesnake master is common at Tucker Prairie, the last sizeable remnant of the Grand Prairie that used to cover a large portion of northern Missouri.

The decision not to impose constraints on what each Prairie Fork planting needs to look like gives MDC considerable freedom in terms of evaluating success.  That freedom led to some great discussions about what success should/could look like.  There were three tour stops where the topic came up in some form, and each is worth discussing.

1. The first discussion occurred early in the tour when we were looking at a soybean field that was going to be converted to prairie vegetation within the next few years.  Around the edge of the field were “waste areas” of tall fescue with infestations of sericea lespedeza, autumn olive, and other invasive plants and trees.  Because of the trees and topography, it wasn’t feasible to put those areas into cultivation, which is the technique MDC (and most of us) would prefer as a way to create a clean seed bed prior to planting prairie.  The group starting talking about other ways those areas might be prepared for planting, until Bill Kleiman (with The Nature Conservancy’s Nachusa Grasslands in Illinois) abruptly shifted the discussion.

Bill made the excellent point that those difficult areas wouldn’t necessarily have to be converted to a diverse prairie planting, and that attempting to do so might prove to be overwhelmingly time consuming or simply impossible.  The seedbank of invasives in those areas is probably heavy enough that even multiple years of cultivation might still result in long-term fights with invasive plants emerging from that seedbank long after prairie vegetation was planted.  Instead, Bill suggested, why not implement an annual program of broadcast herbicide spraying in those waste areas – with the simple goal of maintaining them as a low diversity, grass-dominated, plant communities that won’t threaten nearby diverse plantings?  In other words, rather than trying to make those areas perfect, just make them harmless.  Down the road, when everything else is restored, MDC can always come back and spend energy trying to convert them to something diverse.  In the meantime, they can save a lot of time and energy by avoiding a (likely fruitless) battle to convert a very weedy area into a pretty prairie.  It was certainly an interesting proposal.

Rosinweed (Silphium integrifolium) was just beginning to bloom during the GRN workshop.
Rosinweed (Silphium integrifolium) was just beginning to bloom during the GRN workshop.

2. The next site we visited had been planted to prairie vegetation several years earlier, but had a chronic infestation of sericea lespedeza.  While MDC staff was controlling the lespedeza through spot spraying, there was enough lespedeza (and enough spraying) that the area’s plant diversity had become fairly limited and dominated by a few grass and wildflower species.  Chris Newbold, who had been in charge of the restoration work at the time the site was seeded, said that if he had to do it all again, he would have left the area in cultivation a few more years to get better control of the lespdeza population prior to planting.  The more pressing question now, though, was how to deal with the site going forward.  Options included starting over by returning it to cultivation, trying to overseed the area to establish better plant diversity, or just leaving it alone.  An additional proposal was to overseed with plant species that are resistant to a selective herbicide that controls lespedeza, allowing the site to be broadcast sprayed without eliminating all plant diversity.  I don’t think the question was resolved through our discussion, but we built upon our earlier conversation by posing the question, “Does every part of a restoration project have to be ‘perfect’ in order for the project to be successful?”

This portion of Prairie Fork Conservation Area was seeded with a high diversity mixture but has lost plant diversity , at least in part because of years of herbicide spraying for sericea lespedeza.  The lespedeza is spot sprayed, but is abundant enough that herbicide impacts are evident on the plant community.
This portion of Prairie Fork Conservation Area was seeded with a high diversity mixture but has lost plant diversity , at least in part because of years of herbicide spraying for sericea lespedeza. The lespedeza is spot sprayed, but is abundant enough that herbicide impacts are evident on the plant community.  Mike Arduser, of MDC, pointed out that the site looks really nice from a bee habitat standpoint, bolstering the idea that although it had lost some of its plant diversity, it was still an important contributor to the landscape around it.

I appreciated the discussion because it forced me to reflect upon our Platte River Prairies, and areas that I wish looked better than they did.  In both my prairies and at Prairie Fork, it’s really the big picture that’s important.  Within the mosaic of natural communities that make up any sizeable prairie, it’s probably ok to have areas of low diversity vegetation.  At least at the scale of Prairie Fork, it’s really the mosaic that’s important, and variation in plant species composition between individual portions of the landscape is not only acceptable, but preferable.  Coming to terms with the idea that it’s ok to have portions of our prairies/properties that are less diverse than we think they could be is an important part of being a successful land manager.  The alternative probably entails driving ourselves to exhaustion!

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3. The last site we looked at was a 2004 prairie planting that was very diverse and full of big showy wildflowers.  From an aesthetic standpoint, the planting was a big beautiful success.  I asked the MDC staff how they might judge the success of such a planting according to their objectives.  Clearly, one part of the answer is that a showy prairie is useful in terms of getting people to appreciate prairies – so that fits well into education/outreach objectives.  However, Jeff Demand, the current site manager, had another interesting perspective.  Jeff said that he appreciated the planting because it required very little maintenance.  There were no real invasive species issues to deal with, and nothing else about it that screamed out for attention.  The planting was clearly of value to wildlife, pollinators, and other prairie species, but it was particularly nice to have an area that just needed some period burning or similar management.  Especially when budgets and staffing are tight (and when are they NOT?) a site that is attractive and low maintenance can seem like heaven.

This 1994 seeding at Prairie Fork is an aesthetically-pleasing site.  Most people would be very happy to have this kind of establishment success from a prairie planting.
This 2004 seeding at Prairie Fork is an aesthetically-pleasing site. Most people would be very happy to have this kind of establishment success from a prairie planting.  However, aesthetics is not always the best measure of success.

There are no right or wrong answers when it comes to objectives.  Every site has its own, and they almost always change over time.  The important thing is to know what the objectives are for a particular site, and to be measuring whether or not you’re moving in the right direction.  It’s always nice to hear about other people’s objectives and measures, because it makes us re-examine our own.

I tend to worry more than I should about portions of our site that aren’t as “nice” as I think they should be.  The field trip discussion was a great reminder to sto obsessing about small areas and keep the big picture in mind.  It’s important to deal with areas that might negatively influence the surrounding landscape (e.g., by providing a foothold for invasive species that can spread into nearby areas).  Otherwise, however, variation between portions of a prairie or prairie landscape just adds to the diversity – and resilience – of the ecosystem.  I think that’s a good thing.

I guess I just have to be reminded of that now and then.

The Annual Grassland Restoration Network Workshop – Coming to A Prairie Near You (If You’re Near Columbia, Missouri)

The Grassland Restoration Network is a loose affiliation of those of us trying to use prairie restoration (reconstruction) as a way to rebuild, conserve and sustain grassland ecosystems.  Each year, we put on a workshop to share ideas, techniques, research results, and stories with other.  Workshops are hosted by a different site each year, giving us the opportunity to visit a range of projects over the years. 

Kicking the dirt together helps us better understand challenges and strategies being employed at each others’ sites, but also stimulates better discussions than when we’re sitting in a sterile hotel conference room.  The workshops tend to minimize lectures and maximize both formal and informal discussion time.  I missed the 2012 workshop, but you can read my posts about the 2011 workshop in Indiana by clicking here.

A field discussion at the 2009 Grassland Restoration Network in Nebraska.
Bill Whitney, of Prairie Plains Resource Institute, leads a field discussion during the 2009 Grassland Restoration Network in Nebraska.

This year’s workshop will be hosted by the Missouri Department of Conservation in Columbia, Missouri from July 16-18.  If you are interested in attending, you can download the preliminary agenda and registration information by clicking here

In addition, you can follow the activities of the Grassland Restoration Network on our new blog/website, initiated by Bill Kleiman, at Nachusa Grasslands.  That link is here.

Is Poison Hemlock Repelled By Plant Diversity? Early Results Say Yes

How important is plant diversity?  Most ecologists think it’s a critical component of resilient ecosystems.  Last week I collected some data that lends support to that view.  In some experimental prairie plantings we’ve established in our Platte River Prairies, plant diversity appears to be suppressing the invasion of poison hemlock (Conium maculatum).

A floristically rich restored prairie, in which prescribed fire and grazing are being used to maintain high plant diversity.  The Nature Conservancy's Platte River Prairies, Nebraska.
A floristically rich restored prairie, in which prescribed fire and grazing are being used to maintain high plant diversity. The Nature Conservancy’s Platte River Prairies, Nebraska.

Back in 2006, I established some research plots in our Platte River Prairies so we could take a more experimental approach to our work to understant how plant diversity affects prairie ecosystems.  Those research plots consist of 24 squares, each of which is 3/4 acre in size.  Half of those plots were planted with a high diversity seed mixture of about 100 plant species.  The other half was planted with a lower diversity mixture of 8 grass and 7 wildflower species.  Since then, several university researchers have helped us collect data on the differences between those high and low diversity plantings.  We’ve looked at a number of variables, including soils, drought response, insect populations, insect herbivory rates, and resistance to invasive species.

An aerial photo of our 2006 diversity research plots.  Each plot is 3/4 ac (1/3 ha) in size and is planted with either a high diverisity (100 species) or low diversity (15 species) seed mixture.
An aerial photo of our 2006 diversity research plots. Each plot is 3/4 ac (1/3 ha) in size and is planted with either a high diverisity (100 species) or low diversity (15 species) seed mixture.

Kristine Nemec, a recent PhD from the University of Nebraska-Lincoln, has done the bulk of the data collection and analysis from those experimental plots.  A soon-to-be-published research paper from that work will report that plant diversity appears to be suppressing the spread of two invasive species: bull thistle (Cirsium vulgare) and smooth brome (Bromus inermis).  Poison hemlock wasn’t included in that project because the methods we chose for measuring vegetation weren’t well suited to capture its presence and abundance.  However, from a purely observational standpoint, it’s always appeared that a lot less hemlock grows in the high diversity plots than in the low diversity plots.  Last week, I decided to test that observation by collecting some data.

Poison hemlock (Conium maculatum) has invaded portions of our research plots, sometimes forming large colonies that are near monocultures.
Poison hemlock (Conium maculatum) has invaded portions of our research plots, sometimes forming large colonies that are near monocultures.

Since hemlock is abundant mainly in the southern half of our 24 plots, I only collected data from those 12 plots for this pilot effort.  Half of those 12 plots had been seeded with a high diversity mixture and the other half with a low diversity mixture.  I walked three transects across each of those plots, and counted the number of last season’s hemlock stems that were within a meter of me on either side.  I only counted stems that still had seed heads to help ensure that I wasn’t counting stems from multiple years’ production.  You can see the results of my counts in the graph below.

The number of poison hemlock flowering stems found by transect in low diversity and high diversity plots.  Platte River Prairies - Diversity Research Plots.  April 2013
The number of poison hemlock flowering stems found by transect in low diversity and high diversity plots. Platte River Prairies – Diversity Research Plots. April 2013

Although I haven’t yet run any statistics on these data, there is a striking difference in the number of poison hemlock plants between the two treatments.  Hemlock was rare in the high-diversity plots, but was found in large numbers in many of the transects through the low-diversity plots.  This was just a quick and dirty pilot effort to see if there was enough difference to warrant a full-fledged research project, but I feel pretty comfortable that plant diversity is having an impact on hemlock abundance.

I plan to collect some more comprehensive data on poison hemlock this summer.  I’d also like to collect the same kind of data from an adjacent set of plots we established in 2010.  Those newer plots are the same size as those from 2006, but include three different seed mixtures: high diversity, low diversity, and a monoculture of big bluestem.  If I see a similar pattern of hemlock abundance there, that will go a long way to confirm what I think I’m seeing in the 2006 plots.

I’ve never considered poison hemlock to be a particularly dangerous invasive species in our Platte River Prairies.  It seems to be most abundant in old woodlots, and doesn’t often show up in our native or restored prairies.  On the other hand, the plant’s toxicity can cause big problems, especially from an agricultural perspective.  In fact, we’d considered haying our research plots last summer but couldn’t find anyone to harvest them because hay containing poison hemlock can’t be fed to livestock.  If prairie plantings with a high diversity of plant species resist invasion from hemlock, that could have important ramifications for farmers who want to establish new grasslands for hay or grazing production.

Poison hemlock is most often found in old woodlots along the Platte River.  It's unusual for us to find it in our diverse prairies.
Poison hemlock is most often found in old woodlots along the Platte River. We don’t usually see it in our diverse prairies.

My little pilot study is a small addition to a growing list of other research projects demonstrating the value(s) of plant diversity.  Unfortunately, high diversity prairie plantings are more expensive than lower diversity plantings, so it’s important for landowners and conservation organizations to know exactly what they get for that higher cost.  High plant diversity provides nectar and pollen resources for pollinators, improves total vegetative production, and has other benefits, including quality wildlife habitat.  However, one of the most intriguing aspects of plant diversity is its potential to help suppress invasive species.  If we continue to find that more diverse plantings help repel species such as bull thistle and poison hemlock, that will have important implications for both agricultural producers and wildlife/prairie managers.

Stay tuned as we keep learning…

The Right Metaphor for Prairie Restoration

Prairie restoration can be a powerful tool for grassland conservation, but we’re not taking advantage of its full potential.  Too often, we think and talk about prairie restoration (aka prairie reconstruction) in the wrong way.  Instead of trying to restore an ecosystem, we try to reproduce history.

Nelson Winkel, land manager for The Nature Conservancy’s Platte River Prairies, harvests grass seed using a pull-behind seed stripper.

I was in Washington D.C. a couple weeks ago and visited Ford’s theater, where President Lincoln was assassinated in 1865.  After the death of the president, the building went through drastic changes, including being completely gutted after a partial collapse of the interior.  By the time the decision was made to restore the building for use as a historic site, the National Park Service basically had to start from scratch.  Regardless, through painstaking research and a lot of hard work, the theater was rebuilt to closely resemble Ford’s theater of 1865.

The rebuilding of Ford’s theater is a decent metaphor for much of the early prairie restoration (or reconstruction) work dating back to the 1930’s in North America – as well for some of the restoration work that continues today.   In the case of prairie restoration, someone identifies a tract of land that used to be prairie but has been converted into something completely different (usually cropland), and tries their best to restore what was there before it was converted.  Just as in the restoration of Ford’s theater, the prairie restoration process requires lot of research and hard work to identify, find, and reassemble what had been there before.

Unfortunately, the Ford’s theater approach has turned out to be a poor fit for prairie restoration.  Prairies aren’t buildings that have specific architectural plans and well-defined pieces that can be collected and assembled to create a pre-defined end product.  Prairies are dynamic ecosystems that are constantly changing and evolving, and their components include organisms that interact with each other in complex ways.  Trying to recreate a prairie that looks and functions just as it used to – especially on a small isolated tract of land – is nearly impossible.

Reseeded prairie at The Nature Conservancy’s Kankakee Sands Restoration Project in Indiana. If the plant community today looks different than it did before it was farmed, is that really a failure of the restoration project?

That doesn’t mean small scale prairie restoration is a bad idea.  I think reestablishing vegetation that is similar to what was at a site many years ago can have tremendous historic and educational value, and can also provide important habitat for many grassland species.  Where this kind of prairie restoration falls flat is when we expect too much from it.  It’s really easy to find glaring differences between the restored prairie and what we know or think used to be there – soil characteristics are different, insect and wildlife species are missing, plant species are too common or too rare, etc.  These “failures” have led some people in conservation and academia to become disillusioned with the whole concept of prairie restoration.

In reality, prairie restoration has proven to be very successful, and is a tremendous tool for grassland conservation.  We just need to find and apply a better metaphor.

A Better Metaphor for Ecological Restoration

Unlike efforts to restore old buildings, prairie restoration projects should not be aimed at recreating something exactly as it existed long ago.  Instead, effective prairie restoration should be like rebuilding a city after large portions of it are destroyed in a major disaster.  When reconstructing a metropolitan area, replicating individual structures is much less important than restoring the processes the inhabitants of the city rely on.  The people living and working in a city depend upon the restoration of power, transportation, communication, and other similar functions.  Those people don’t care whether roads, power lines, or communication towers are put back exactly as they were before – they just want to be able to get the supplies and information they need, and to travel around so they can to do their jobs and survive.  Restoration success is not measured by how much the rebuilt areas resemble the preexisting areas, but by whether or not the city and its citizens can survive and thrive again.

Similarly, restoration of fragmented prairie landscapes should not be an attempt to recreate history.  It should be an attempt to rebuild the viability of the species – and, more importantly, the processes – that make the prairie ecosystem function and thrive.  Success shouldn’t be measured at the scale of individual restoration projects, but at the scale of the resultant complex of remnant and restored prairies.  Are habitat patches sufficiently large that area-sensitive birds can nest successfully?  Are insects and animals able to travel through that prairie complex to forage, mate, and disperse?  Are ecological processes like seed dispersal and pollination occurring between the various patches of habitat?  When a species’ population is wiped out in one part of the prairie because of a fire, disease, or other factor, is it able to recolonize from nearby areas?

Pollination is an example of an important process that drives prairie function. Increasing the size and/or connectivity of prairies by restoring areas around and between prairie fragments can enhance the viability of pollination and other processes.

At first glance, choosing the appropriate metaphor for prairie restoration may seem insignificant compared to other challenges we face in grassland conservation.  However, if we’re going to successfully restore the viability of fragmented prairies, we can’t afford to waste time and effort worrying about whether or not we’ve matched pre-European settlement condition, or any other historical benchmark.  Instead, we need to focus on patching the essential systems back together.

After all, we’re not building for the past, we’re building for the future.

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Read more on this subject…

– An earlier blog post about using prairie restoration as a landscape scale conservation tool.

– A prairie restoration project case study, with ideas about how to measure its success.

– Some recent early attempts we’ve made to measure restoration success by looking at the responses of bees and ants.

– A post about the importance and definition of ecological resilience in prairies.