Choosing Your Destination Before You Choose Your Mode of Transport

Last week, I attended a science and stewardship conference of The Nature Conservancy in Madison, Wisconsin.  It was an inspiring and thought-provoking week.  There were a lot of topics that will provide fodder for future blog posts, but I wanted to start with an issue that came up in several sessions.  The topic had to do with setting appropriate objectives for conservation strategies, and for land management in particular.  In short, it’s really important to make sure we’re not setting objectives that are focused on strategies rather than outcomes.

This mixed-grass prairie is managed with both prescribed fire and grazing.  However,  neither fire nor grazing is the objective, they are tools that are strategically employed to create desired outcomes.  Gjerloff Prairie – Prairie Plains Resource Institute

Here’s an illustration of what I mean.  If I was planning a vacation for next summer, I probably wouldn’t start with the following question: “What mode of transportation should I take on my vacation next year?”

Clearly, it’s tough to answer that question without knowing more about the ultimate objectives of the vacation.  Where do I want to go?  What time of year am I going?  How many people are going with me?  If I’m planning to travel from Nebraska to Ireland, I probably won’t be able to do that by bus.  I could conceivably travel by motorcycle (if I had one) to the Rocky Mountains, but probably not if I was going during the winter or planning to take little kids with me.

It seems silly to start by thinking about how to get somewhere before deciding where to go, but as land managers, it’s easy to fall into exactly that mindset.  We sometimes set objectives about using fire or grazing, for example, instead of first defining the outcome we want and then thinking about what tools and strategies might get us there (which may or may not include fire or grazing).  In this post, I’ve provided examples of how this trap can present itself, both to managers of conservation land and private landowners, and some thoughts about how to avoid the trap.

Significant research has helped us understand the kinds of fire and grazing patterns under which North American prairies developed.  For example, in many places, we have a pretty good idea how often a particular site burned, on average, before European settlement.  We also have reasonably good information on the presence, abundance, and behavior of historic grazers.  Based on that information, a land manager could decide that the best management for their prairie would be to reinstate, as closely as possible, the timing and intensity of historic fire and grazing that site likely evolved under. 

Historically, prairies in this region probably burned on an average of every 4-5 years.  However, within that average range, there would have been wide variation.  More importantly, this prairie sits within a very different landscape today, with challenges not faced by those historic prairies.

Patch-burn grazing is often described, for example, as “mimicking historic fire and grazing patterns.”  Mob grazing advocates trumpet (though I’m skeptical) that their system replicates the way bison moved across a landscape.  Some in the Upper Midwest region of North America point to research showing high populations of indigenous people and scarce evidence of abundant bison and argue that their prairies should be managed only with fire.  We can argue about all three of those examples – and many more – but the bigger point is that none of those arguments should determine our management strategies.  Again, we shouldn’t be setting objectives about the strategy we want to use without first identifying the outcome we want.

To make a clunky return to my vacation travel analogy, it would be silly of me to choose horseback as my preferred mode of transportation across the Great Plains to the Rocky Mountains just because it’s what worked several hundred years ago.  Today’s landscape is broken up into countless fenced off private land parcels, which would make cross-country horse travel difficult, to say the least.  In addition, there is a pretty nice set of modern opportunities (roads and vehicles) I can take advantage of nowadays.

Likewise, our prairies exist within a different world today, with a new set of challenges and opportunities.  Mimicking historic disturbance regimes won’t necessarily keep prairies in good shape in a world with habitat fragmentation, massive invasive species pressure, climate change, nitrogen deposition, and other factors.  And speaking of good shape, our first and primary concern should really be to define what “good shape” is, right?  Are we managing for plant diversity or a few rare plants?  Are we trying to sustain diverse bird populations?  Habitat heterogeneity? Is ecological resilience the goal?  If so, what are the factors driving resilience, and how to we sustain those?  There are countless reasonable goals for land managers to choose from, many dependent upon scale, but those goals should be based on the outcome we want.

This annually-hayed prairie maintains high plant diversity but provides only one type of habitat structure for nesting birds and other wildlife species.  Depending upon the objectives for the site, that could be fine, but it very much depends upon what the manager wants to accomplish.

I feel it’s important to say this here:  I am a big proponent of both fire and grazing as management tools – you can find myriad examples of that by searching through my previous blog posts.  However, while I think combining fire and grazing can create some fantastic results, those strategies/results don’t fit all objectives.  More importantly, your particular site may or may not respond well to those kinds of fire and grazing combinations.

Let’s say your primary objective is to provide habitat for as many species of grassland birds as possible.  First, you’ll need a pretty big swath of land – many bird species have minimum habitat size requirements.  Assuming you’ve got sufficient land, the major factor grassland nesting birds respond to is habitat structure.  Some birds prefer tall thatchy structure, others like short/sparse vegetation, and others want something in-between.  A reasonable outcome-based objective might be that you want to provide all three of those habitat types across your prairie each year (and you’ll want to make sure the habitat are being successfully used by a diverse bird community).  Perfect.  Now, how will you create those habitat types?

 Grasshopper sparrows tend to nest in prairies with relatively short structure, but with some thatch (which they use to build nests) along the ground.  Some of the highest abundances of grasshopper sparrows around here are found in relatively heavily-grazed prairie.

Fall or spring fires can create short habitat structure that some birds really like to nest in.  However, some bird species (e.g., grasshopper sparrows) usually like short habitat with a little more thatch in the ground layer than is usually found in recently burned prairies.  Also, while burned areas are short and unburned areas are tall, it’s difficult to create in-between height/density habitats using only fire.  This is where other tools such as mowing and grazing might be helpful.  Mowing can reduce the height of tall vegetation and create short or mid-height structure that grasshopper sparrows, meadowlarks, and other species prefer.  Grazing can do the same and can have the advantage that cattle or bison are selective grazers, eating some plants and leaving others.  This can create structure with both tall and short vegetation mixed together and can also help suppress grasses and allow for greater expression of forbs (broadleaf plants) – something birds such as dickcissels often prefer.

Upland sandpipers prefer to nest where vegetation structure is short, but often move to sites with strong forb cover and a little patchier structure when their chicks become active.

If we’re trying to create optimal bird habitat, then, fire, mowing and grazing might all be useful tools to consider.  It’s important to understand how each tool can be used to affect habitat structure, as well as the potential risks of using each (fire can sometimes kill aboveground animals and stimulate invasive plants, grazers can sometimes target vulnerable plants and create issues via trampling).  With all of that information, you can start putting together strategies that employ the right tools, and then test those strategies against the OUTCOMES you desire.  Notice that the process I’ve just described is independent of the kinds of historic fire returns for your area or whether or not you think grazing was a significant factor in the evolution of regional plant communities.  Define your objective by the outcomes you want and test/adapt strategies based on that objective.

Other examples: At my family prairie, we aren’t using prescribed fire because we’ve been able to use grazing to meet our objectives of habitat heterogeneity and increasing plant diversity, and we use loppers/herbicide to successfully control woody invasion.  In small prairies where preserving particular plant species is the objective, a strategy using only fire or mowing could be most appropriate.  If that small prairie has rare insects or reptiles that are especially vulnerable to fire, maybe mowing is the best tool.  Regardless, the right tools and strategies depend upon the outcome-based objective.

This photo was taken in the burned patch of a patch-burn grazed prairie at Konza prairie, near Manhattan, Kansas.  The grazing created varied habitat structure because of the selective grazing by cattle.  Leadplant and other ungrazed forbs contrast with surrounding short grasses.

For ranchers and farmers who manage prairies, this same objective setting process should apply, but of course those prairies also have to help provide sufficient income to keep a family or business thriving.  Even in those cases, however, it’s still important to start with outcome-based objectives.  Those objectives can include a certain amount of needed income but should also include specific habitat or other ecological objectives.  Once you’ve decided, for example, that you really want to manage in a way that provides a certain amount of quail habitat or provides consistent pollinator resources through the season, you can look for ways to accomplish that while still providing the needed income.  When a conflict between income and habitat objectives arises, you can make the decisions that make sense to you, but at least you’re making those decisions with all the information needed to fully consider the options.

Prescribed fire can be a great tool for accomplishing some objectives, but it can also be difficult to implement for some managers.  While it is an important ecological process in prairies, employing prescribed fire should still be seen as a tool/strategy, rather than as an objective in and of itself.

There are plenty of reasonable prairie management objectives to choose from, but they should be based on outcomes rather than on tools and strategies.  Employing more frequent prescribed fire is not a good objective.  However, using more frequent prescribed fire might be a great strategy to reach a particular outcome.  (It could also be a terrible strategy, depending upon your objective.)  Don’t fall into the trap of choosing your transportation method before you know where you want to go. 

P.S. I’m sure some of you are thinking it, so let me address what might appear to be a weakness of my vacation transportation analogy.  Yes, it’s perfectly fine to start vacation planning by deciding that you want to take a cruise ship or motorcycle if the OUTCOME you really want is to ride on a ship or motorcycle.  If you don’t care where you go, the destination isn’t the outcome, it’s just a by-product of your mode of travel.  Fine.  But I think you understand what I was trying to say, right?  Sure, you could argue that conducting prescribed fires could be your objective if all you want is a legal way to light things on fire and watch them burn.  If that’s your objective, though, you’re not managing prairies, you’re lighting things on fire – and there’s a big difference.  Ok?  Ok.

Properly Portraying the Power of Prescribed Fire

At a recent Nebraska conference, Shelly Kelly of the Sandhills Task Force made a point worth some serious consideration.  She told a roomful of wildlife biologists that if they want reluctant ranchers to seriously consider using prescribed fire, using photos of big scary flames in presentations and social media posts is probably counterproductive.  Instead, Shelly suggested sharing more photos of fires that are clearly under control, with people calmly working around them.  Even better, she suggested, we should share photos of green grass beneath the skeletons of dead invasive trees, showing the positive results that follow fire.

We got our first prescribed fires of 2018 done last week.  This photo captures some of the 5 minutes or so of intense fire following about an hour of boring backing fire lines on one of those burns.

I appreciate her point.  Most of my favorite prescribed fire photos are the ones I took during the big head (wind-driven) fire at the end of a burn – when the flames are high and there’s lots of color and action.  Visually, those images are certainly more powerful than photos of a small fire backing slowly into the wind during the early stages of a burn.  However, it’s important to remember that “powerful” might not be the attribute to lead with when talking to a skeptical audience that fears the potential negative consequences of fire.

On the other hand, I don’t necessarily think we need to stop showing people powerful images of fire – we should just try to provide appropriate context for those images.  After all, the power of fire is why it’s so valuable as a management tool.  It can take some pretty tall flames and a lot of heat to kill eastern red cedar trees, for example.

Context is important.  Posting an image of huge flames and a towering smoke column on Instagram or Facebook with a short caption like, “Woo Hoo!!  We had a great burn today!!” will probably get lots of likes from experienced fire folks.  However, someone unfamiliar with prescribed fire might look at that same image and assume it was taken by a reckless pyromaniac who was endangering the public and him/herself.  As a result, that person might be much harder to turn into a prescribed fire supporter.

Expounding a little in an image caption can help quite a bit.  Something like, “Here’s an image from the finale of today’s controlled burn.  After two hours of slowly burning out a boundary around our fire unit, we were able to send this hot fire through the prairie to kill lots of invasive trees before it ran into what we’d burned earlier and put itself out.”  Or whatever – you get the idea.

We start each burn with a small test fire in the downwind corner . That gives us a chance to see how the fire and smoke are going to behave before we commit to the whole enchilada. If we don’t like what we see, we can easily shut down and wait for a better day.  Last week, we had dry conditions, but wind speeds were low enough that we could burn safely.

Even better, we should probably share broader series of images showing the entire process of the fire, including the boring backing fire that sets the stage for that big finish.  Photos of a nice straight firebreak, with black on one side and unburned grass on the other, can help drive home how careful, competent, and effective we are.  After posting a few shots of people in yellow suits laying down lines of small flame inside neat boundaries, it’s probably ok to slide in a couple photos of flaming infernos and torching cedar trees.  It might be smart to include at least one more photo after those flashy shots, though, showing that everything turned out well in the end…

In this photo, we’re laying down a band of water along the edge of a mowed strip surrounding our burn unit, and Olivia is lighting the grass just upwind of that wet and mowed line.
With both a wet line and a mowed firebreak to catch it, Alex lit a line of fire that we allowed to back into the wind. Several vehicles with water followed behind to make sure the flames stayed inside the unit.
Eventually the backing fire created a wind band of black that acted as a catcher’s mitt when the big fire ran into it later.
Once the black lines were prepared, we ignited the upwind portion of the unit and allowed fire to roar through the unit until it hit the black and was extinguished.
These lines of fire are safely inside wide bands of black that have already burned.
Olivia watches the last of the smoke dissipate as the fire burns itself out.

I’ll try to follow my own advice about fire communications in the future, and you can remind me when I forget.  It’s absolutely appropriate to celebrate the power (and let’s face it, the beauty too) of fire by taking and sharing photos.  However, we should also celebrate and share the care and strategy that go into making those powerful fires safe and effective.

Be safe out there.

Burning For Good Reasons

At the Platte River Prairies, we conduct prescribed burns for various purposes.  Some fires are intended to kill eastern red cedar trees or to suppress cool-season invasive grasses.  Other fires are aimed at removing thatch and old vegetative growth – creating lush regrowth that concentrates cattle grazing in one portion of a prairie.  For each objective, we prescribe a certain set of outcomes that need to be met in order for a burn to be successful, and a parallel set of conditions (especially timing and weather conditions) that will get us to those outcomes.  If we’re just trying to remove most of the old dead growth from a prairie, we don’t need the same kind of fire intensity as when we’re trying to kill cedar trees.  If we’re targeting cool-season grasses (and won’t be following up with grazing), we try to burn about the time those grasses are starting to flower.

On the last day of March this year, we assembled a crew that combined our staff with employees from the Central Platte Natural Resources District and got ready to burn some hilly sand prairie.  Our objective was to remove at least 75% of the thatch and old growth from the burned area so subsequent cattle grazing would be focused in that burned patch while the remainder of the prairie went largely ungrazed.  The forecast had predicted pretty high relative humidity readings, but we thought we’d be ok as long as we didn’t have overnight fog or mist.  Unfortunately, on the morning of the fire, the grass litter along the ground was more damp than we’d hoped and since the sun was hidden behind clouds it didn’t seem likely that litter would dry much.  After considerable discussion and delay, we finally decided to conduct a test fire in the downwind corner of the burn unit to see what kind of burn results we’d get before deciding whether or not to burn the entire 70 acre unit.  We also figured it was an opportunity to learn more about how fire behaves under humid conditions.  At 1 pm, it was 46 degrees F, 71% relative humidity, and we had winds at about 10 mph.

Nelson Winkel, our land steward, had to work pretty hard to get the grass ignited. While it looks like there’s a lot of fire here, watch the video below to get a better picture of how the fire was actually burning.  The flames would flare up when they hit a patch of grass with dry leaves, but the damp litter layer kept the flames from moving very quickly or burning all the way to the soil surface.  (If the video doesn’t work, click on the title of this post to open it in a browser or follow this link: https://www.youtube.com/watch?v=p3Dh2OqzmEk)

The test fire was definitely instructive.  The upper portions of grass plants were sufficiently dry that they burned fairly well, but the dampness along the ground made the fire creep along very slowly, even when pushed by the wind.  Following along behind the fire, I was kicking away ash to find that quite a bit of litter was still unburned and covering the soil.  After we burned an area about 40 x 40 feet, we extinguished the fire and had a group discussion.  The grass was burning well enough that we could probably burn the unit, and much of the area inside the firebreaks would ignite and turn black.  On the crests of the hills where vegetation was dominated by bunchgrasses and there was considerable bare ground beneath plants, we’d probably get a pretty complete burn.  However, in lower areas where there was more dense vegetation, including some cool-season invasive grasses, we didn’t feel like it would burn very completely at all.  In total, we didn’t think we’d reach our goal of removing litter from 75% of the area.  Importantly, the areas that wouldn’t burn well (and thus wouldn’t attract grazing) were the ones we most wanted cattle to graze (to suppress invasive grass growth).  After talking through our options with the whole crew, we decided to postpone the burn until we had a day with better conditions.

You can see from this photo that while most of the dry standing vegetation burned, much of the litter/thatch remained behind.
Here’s our group, deep in discussion about objectives, results, and whether or not to continue with the fire.

It’s never an easy decision to call off a burn when you’ve got crew and equipment on site.  As a burn boss, I’ve had to do that multiple times, but usually when we’re worried about safety because the weather conditions are too far on the hot, dry and/or windy side.  In this case, there were no extraordinary safety concerns, but every fire comes with risks to people and property.  It never makes sense to burn and not achieve the desired result.  We needed near complete consumption of the dead vegetation to attract cattle grazing and carry out our management plan for that season.   Since we weren’t going to achieve that, we didn’t burn.

As it turned out, we only had to wait four days for another opportunity to burn that unit.  On April 4, most of the same crew members assembled and we set up to try it again.   Our weather conditions at 11 am weren’t all that different from our previous attempt (46 degrees F, 65% RH, and 12-15 mph winds) but the grass litter was much drier, and while the sky was cloudy, the clouds were more patchy and the sun was even popping through once in a while.

Our downwind firebreaks were two gravel roads, so it didn’t take long to get those lines lit and blacked out.  At that point, however, I walked out into the black to see how much litter consumption we were getting.  While it was much better than the previous week, there were still some unburned patches.  Since we had solid firebreaks, we paused ignition to wait for everything to warm up and dry out just a little more.   About a half hour later, relative humidity had dropped nearly 10% and the temperature had risen about 5%.  We restarted ignition and pretty quickly finished up the rest of the fire.

On our second attempt, we had much better fire behavior. Here, a fire is backing uphill through vegetation and getting pretty complete consumption.
Nelson is walking through the black in a low spot where not all the litter was burning well. This was while we were waiting for the humidity to drop a little more.

Here are a couple timelapse videos of the lighting of the “flanking head fires” toward the end of the burn.  They are a little jumpy (sorry) because I was just hand-holding my phone and taking repeated photos, but it shows how different the fire behavior was from the slow creeping fire of our first attempt 5 days earlier.  If you can’t see the videos, click on the title of this post to open it in a web browser or click on these links: Video 1, Video 2.

Here is what the burn unit looked like right after the fire. You can see lots of pocket gopher mounds scattered through the black, but also a few small unburned patches. Those unburned areas are perfectly fine with us, and actually provide some valuable areas of refuge for animals (in addition to the 2/3 of this prairie we didn’t burn and other prairies across the road in three directions.)

I’m glad we waited for more favorable conditions to burn this unit.  We wouldn’t have accomplished what we needed to on the first day, and though it was hard to turn down a potential burn opportunity and assembled crew, I think we made the right call.  As it happened, we didn’t have to wait long for a better day, and we got what we wanted out of that fire.  At the same time, I’m also glad we decided to try a test fire on the first day.  It turned into a good learning experience and fodder for fruitful discussion among the crew.  The whole situation was a good reminder that while we can achieve many important objectives through prescribed burning, it isn’t a toy we play with for fun.  Instead, we want to burn only when we can do so safely, and when we can achieve clear and specific objectives.

If you want to learn more about how we combine prescribed fire and grazing to manage for habitat and species diversity, you can read more here.

Pill Bug Mystery

Last November, we conducted a prescribed burn at a 3-year old restored prairie.  Two weeks later, I was surprised to be able to photograph green regrowth in that area.  Last week, I revisited the same burned area and got yet another surprise.  Thousands and thousands of dead pill bugs (aka sow bugs, roly polies, wood lice) lay scattered across the ground.

Pill bugs
Dead pill bugs in a prairie burned last November.
cluster
The distribution of dead critters wasn’t consistent across the site, but there were a lot of areas like this with big numbers.

After I found the first few, I noticed them everywhere.  White skeletons of pill bugs, lying on top of the ground – sometimes in large aggregations, other times just a few here and there.  If I’d randomly tossed a hoola hoop on the ground 100 times, I bet I’d have found at least a couple dead pill bugs inside the hoop after 97 out of 100 of those throws.

isopod
I think these pill bugs were probably Armadillidium vulgare, which is a pretty good descriptive name for them.

When I got home, I looked through my photos from last November to see if maybe the dead pill bugs had been on the ground back then too.  If they were still dark gray, instead of white, I might not have noticed them.  Out of about 30 photos, I did find one bug, and it was still dark.  It’s certainly possible there were many more bugs on the ground, hidden by a combination of their dark color and the remaining ash and debris that has since largely disappeared. I’d like to think I would have noticed that many, but I’m not very confident of that.

november
A single pill bug can be seen in this photo from mid-November last year.

I like mysteries, but I also like understanding ecological phenomena.  Pill bugs are detritivores; they feed on dead and decaying material on and below the soil surface.  One possibility is that the dead pill bugs had been feeding above ground, within the layer of thatchy dead vegetation, and were killed by the fire.  A second possibility is that they were belowground during the fire, but came up after the fire (maybe it got too cold and/or dry because the protective thatch was burned away?) and then died aboveground.  There are lots of other possibilities as well, not all of them related to fire.

I emailed photos and questions to several entomology friends, asking for help explaining what I’d seen.  None had ever seen something like this after a fire.  Based on their responses, though, my first proposed scenario (above) seems the most likely.  I just wish I’d looked more carefully after the fire last November, though there wasn’t any reason to do that at the time!  One of my friends also mentioned that I shouldn’t lose any sleep over what happened since the pill bugs are an introduced species (native to the Mediterranean region) and could be having negative impacts on the native detritivore community in prairies.

caught in grass
There were clusters of dead pill bugs in basal clumps of grasses like this one.  Maybe they got lodged here during a strong wind?

This is the kind of thing that keeps me interested in ecology.  Something killed a lot of pill bugs in that prairie.  It was probably related to the fire, but I can’t even say that for sure.  If it was the fire, were there other creatures similarly impacted, but in a less visible way? (We try not to burn entire prairies because of this kind of potential impact, especially on insects overwintering aboveground.) What impacts might the loss of that many pill bugs have on other detritivores, on the decomposition process in that prairie, or on other aspects of prairie ecology?  Lots to ponder; I love it!

Has anyone out there seen anything like this before?  Any other suggestions as to what might have happened?

PLANT GAME ANSWERS:

Thanks to everyone who played the plant game this week.  Over 360 people guessed on the first question, and over 60% guessed correctly that “Widespread Panic Grass” was made up.  Nice work, though I did purposefully try to make the first one easy.

The second question got many fewer guesses, only about 200, as of my writing this.  I got most of you on this one.  Almost half of the guesses were for Yerba Mansa, but that’s a real plant, folks.  It’s a rhizomatous semi-succulent plant in the lizard’s-tail family (Saururaceae) – I PROMISE I’M NOT MAKING THIS UP – and is most common in the southwestern United States, but has at least one record in western Nebraska.

The correct answer for the second question was “Jagged-edge milkwort,” which doesn’t exist.  It’s a little tricky because milkwort is a real thing, but there is no such thing as a “jagged-edge milkwort”.  Only 14% of guessers got it right.  Congratulations to you 30 people!

It looks like people enjoyed playing the game, so we’ll try it again in the near future.

Photo of the Week – November 18, 2016

Back in April, I wrote a post about the regrowth after one of our spring prescribed fires.  That’s a fun time of year to burn because the growing season is getting started and the response of green plants pushing through the black ash comes strong and fast.  Typically, fall burns don’t show any green-up until the next spring.  This year, however, the crazy warm weather has changed things a little. In the two burns we’ve done this fall, most of the ground is still black and barren, but here and there, some green is pushing up through the ash as well.

Here are some photos I took this week of a burn we conducted two weeks earlier.  The site was a recently restored prairie (2013 planting) and this was the first burn at the site.  Green plants weren’t the only interesting things I found as I walked around.

Big bluestem skeletons
Big bluestem skeletons stand tall in the ashes.
Cedar tree
Cedar trees are uncommon on our land because of our consistent use of fire.   This one won’t give us any more trouble….
Some grasses and sedges
Despite the lateness of the season, patches of grasses and sedges were showing signs of growth, taking advantage of warm days and some recent rain.
g
Sedges often stay green well into the winter, but I was still surprised to see these actively growing after a fire.
Goldenrod galls
Among the scorched plants were goldenrod stems with galls.  The insects in these galls left well before the fire, but there other invertebrates overwinter in aboveground plants and are vulnerable to dormant season fires.
Gophers
The bare sand of pocket gopher mounds stand out against the dark background.  Ant hills, vole runways, and mole tunnels were also spread across the burned area.
Sunflower stalks
Most plants burned completely, but in some places, fire intensity was lower and bigger stems of sunflowers and other plants only partially burned, sometimes falling as if they’d been chopped down.
Back fire
Lines of fallen grass and forb stems show where the fire backed into the wind, rather than being pushed by it.  In a backing fire, only the lower parts of plants are consumed, and the wind blows them over into the already burned prairie where they escape being further burned.
skeleton
A white skeleton of a long dead rabbit (I think?) was left tarnished but intact by the fire.
Grasshopper
Near the edge of the burned area, grasshoppers skipped away from my feet as I walked.

Photo of the Week – November 11, 2016

On Wednesday of this week, we took advantage of the eerily warm November temperatures to conduct our second prescribed fire of the fall.  This one will help concentrate some spring grazing in an area where we want to suppress grass dominance and rehabilitate forb diversity.  The fire was also a great opportunity for further training of some young conservation staff.  In addition to Eric and Katharine, our two Hubbard Fellows, we also had three young interns/technicians from a couple of our conservation partners, the Crane Trust and Audubon’s Rowe Sanctuary.

Katharine Hogan, one of our Hubbard Fellows, ignites the west flank of the fire.
Katharine Hogan, one of our Hubbard Fellows, ignites the west flank of the fire.
A firefighter in a UTV with a slip-on pump unit follows Katharine's ignition and prevents the fire from creeping into the mowed firebreak. By this stage in the fire, the wind was mostly blowing the fire into the unit, making this job easier.
A firefighter in a UTV with a slip-on pump unit follows Katharine’s ignition and prevents the fire from creeping into the mowed firebreak. By this stage in the fire, the wind was mostly blowing the fire away from the break and into the unit, making this job easier.
Here, Eric, our other Hubbard Fellow, ignites the head fire, which runs quickly with a tailwind until it is stopped by the backing fire and blackened area at the far end of the unit.
Here, Eric Chien, our other Hubbard Fellow, ignites the head fire, which runs quickly with a tailwind until it is stopped by the backing fire and blackened area at the far end of the unit.  He is followed by another UTV and pump unit.
Nothing to do now but watch.
Nothing to do now but watch.
At the end of every fire, we hold an "after action review" in which every member of the crew shares what went well, what they learned, and what might help us do better in the future.
At the end of every fire, we hold an “After Action Review” in which every member of the crew shares what went well, what they learned, and what might help us do better in the future.

Anyone who has seen prairie fires up close gains an appreciation of their speed, heat, and power.  Harnessing a force like that to achieve prairie management objectives takes careful planning, solid training and good equipment.  The fire this week went as smoothly as could be hoped for, but  – as with every burn I lead – my stomach was still knotted up until the last of the big flames had been extinguished.  After we were done, I took a leisurely and therapeutic walk around the perimeter of the burned area, both to confirm that everything was secure and to envision the positive impact the burn will make as next year’s growing season begins.

Rising from the ashes. Again and again.

Fire and prairies go together like bologna and ketchup.  (There is no discussion about that, by the way, it’s just a fact.)

It’s always fun to watch prairies green up following a prescribed fire.  Plant regrowth is rapid and vigorous, especially after a fire that takes place just as the growing season is starting.  In fact, because the soil warms up faster in recently burned areas, we often see plant species emerging weeks earlier where we’ve burned than in unburned prairies.  The photos below were all taken one week after a fire we conducted at The Platte River Prairies this spring.

Rosin
Rosinweed (Silphium integrifolium) and grasses in restored prairie.
A created wetland
Rainwater filled this created wetland after it was burned, creating excellent habitat for migratory shorebirds and many other creatures in what was formerly a corn field.
False gromwell (Onosmodium molle) was one of the fastest to re-emerge from this spring's burn.
False gromwell (Onosmodium molle) was one of the fastest to re-emerge from this spring’s burn.

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Beautiful two-toned grass shoots were scattered across the entire burned prairie.
Beautiful two-toned grass shoots were scattered across much of the burned prairie.

Photo of the Week – April 17, 2015

We are behind on our burn schedule this year.  The weather hasn’t been great for carrying out safe and effective burns, so we’ve only gotten a few done.  Our prescribed fires are always part of broader management plans, often including cattle grazing, so we have specific objectives for when and how we want a site to burn.  Some plans call for a dormant season fire, other call for a growing season fire.  This spring, we’re already transitioning into the growing season and still have some dormant season fires that we didn’t get done between November and March.  That means we’ll have to adjust our management plans for those properties (as we often do).

During periods of wild weather variability such as those over the last several months, completing a burn is even more satisfying than normal.  Here are a couple photos from a recent fire we used to set up patch-burn grazing and facilitate over-seeding of a degraded prairie.

Mardell Jasnowski lights a "flanking head fire" at a recent burn in our Platte River Prairies.
The Nature Conservancy’s Mardell Jasnowski lights a “flanking head fire” at a recent burn in our Platte River Prairies.
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Here, Mardell is waiting for the rest of the crew to catch up to her.  The ATV driver is pulling a trailer of water and spraying the fire to keep it from creeping into the mowed firebreak.
After the fire is over, the crew relaxes and discusses what went well and what didn't.
After the fire is over, the crew relaxes and discusses what went well and what didn’t.  We share crews with several partners along the river.  In this case, we had help from the Central Platte Natural Resources District.

From the Ashes

Last Friday, I wandered through the small prairie we burned back on March 10.  Even though it is still very early spring, there were already a number of prairie plants popping out of the ground.  I posted photos of this site right after the fire was completed.  Today, I’m posting some photos taken 10 days later at the same site, along with some discussion of the impacts and effectiveness of prescribed prairie fires.

Purple poppy mallow (Calliroe involucrata)
Purple poppy mallow (Callirhoe involucrata) begins its new year of growth.

Most prairie plants grow from belowground buds, making them much less vulnerable to fire than trees and shrubs, which start their new growth above ground – from buds at the tips of branches.  When fire burns woody plants, those aerial buds and living tissue are destroyed, stressing the plants and forcing them to start over from ground level.  However, fire (at least during the dormant season) simply burns up the old stems and leaves of non-woody prairie plants, causing no injury.  Instead removing those dead stems helps stimulate growth in the coming season, especially via increased sunlight, which warms the ground and is available to new shoots as they first emerge.

Scribner's panicum (Panicum oligosanthes), a native cool-season grass.
Scribner’s panicum (Panicum oligosanthes), a native cool-season grass.  In this photo, you can see that the tips of the grass leaves had just started to grow when the fire came through ten days earlier.  Since the leaves grow from the base, those burned tips don’t impede plant growth.

Increased sunlight hitting the ground has helped the small area we burned on March 10 green up much faster than unburned prairie nearby.  Our main objective for the fire was to remove thatch in order to improve the effectiveness of planned herbicide treatment/re-seeding of some smooth brome patches within the small prairie.  The brome is responding very strongly to the fire, and its rapid growth (and the absence of thatch to intercept spray droplets) will make the grass more susceptible to our herbicide treatment.  However, since many other plants are also popping up, we’ll carefully spray only the thickest patches of brome where no other species are growing.

Green sage (Artemisia campestre)
Green sage (Artemisia campestre) growing next to its old stem from last year.

Prescribed fire can be a useful tool when trying to temporarily flip the balance of power from cool-season invasive grasses (smooth brome, Kentucky bluegrass, etc.) to native warm-season grasses (big bluestem, indiangrass, etc.).  However, timing is critically important.  A dormant season or early spring fire is actually counterproductive unless it is followed by herbicide treatment, mowing or grazing.  Those early fires stimulate the growth of cool-season plants – including smooth brome and Kentucky bluegrass – giving them a big advantage over later-season plants which won’t start growth until late April or early May.  By the time those warm-season plants start growing, the early plants will have had a month or more to extract soil moisture and nutrients, and will be big enough to dominate competition for light and root space.

If we’d wanted to suppress smooth brome solely with fire (and not follow up with herbicide), we would have waited until late April or early May to burn.  That late season burn would have stressed the actively-growing brome and bluegrass and provided direct sunlight to freshly emerging shoots of big bluestem and other warm-season grasses.  More often, we combine periodic fire and grazing to suppress brome and bluegrass and facilitate greater plant diversity.

Here's one of the grasses we would like not to see coming back after a fire - Kentucky bluegrass (Poa pratensis).
Along with smooth brome (Bromus inermis), Kentucky bluegrass (Poa pratensis) also responded well to the fire.  This particular plant will likely have a very good year, but the brome and bluegrass in the thicker patches of this prairie will be sprayed with glyphosate herbicide and re-seeded.

The regrowth of prairie plants after fire can seem almost magical.  Fire is absolutely an important natural process and a very useful tool for prairie managers.  However, prescribed fire is not magic, and doesn’t automatically lead to better prairies.  As with any tool, fire has to be applied thoughtfully (and carefully!) in order to meet objectives.

The timing of fire dramatically impacts the way prairie plant communities respond.  Early spring, late spring, summer, and fall fires each have different effects on plants, and those effects are also influenced by soil moisture, the presence/absence of grazers, and many other factors.  Prescribed fire can also have serious impacts on some animals, even during the dormant season.  Many invertebrates, for example, overwinter in the aboveground plant stems or thatch, making them very vulnerable to fire. It’s important not to burn an entire prairie at once – especially if that prairie is isolated from other grasslands.

I'm not sure what species of wildflower this is.
I’m not sure what species of wildflower this is but I’m looking forward to finding out as it gets bigger!

Fire plays many critical roles in prairie ecology – suppressing woody plants, removing thatch, stimulating microbial activity, aiding in nutrient cycling, and more.  However, while fire is important and its effects are both useful and aesthetically pleasing, it is not automatically positive.  Safe use of prescribed fire requires training, experience, and caution.  The effective use of fire requires clear objectives and careful planning that ensures those objectives will be met.

As I’ve discussed before, the actual process of conducting a fire can be very stressful.  However, once the smoke clears and I can relax, its easy to appreciate both the beauty and ecological benefits of prairie fires.  The emergence of bright green prairie plants through black ash is one of my favorite sights, and I love watching plant and animal communities respond and adapt to changing habitat conditions.

In prairies, rising from the ashes is more than a metaphor – it’s a way of life.

 

Photo of the Week – March 12, 2015

We conducted our first prescribed burn of the Spring this week.  It was very small – about an acre or so – surrounded by gravel roads.  The first burn after a long winter is always a little rocky; everyone’s a little out of practice, the crew isn’t yet used to burning with each other, and equipment hasn’t been fully tested…  So it was nice to start small, though the low humidity and warm day made it plenty exciting, even within a small, safe unit.

After the smoke cleared and everyone headed out, I stuck around and poked around in the ashes a little.  I found a patch of prickly pear cactus scorched by the fire, and liked the patterns of color and texture, so I grabbed my camera.

Prickly pear cactus after a prairie fire.  Fire doesn't kill the plants, but does set them back for a while.
Prickly pear cactus after a prairie fire. Fire doesn’t seem to kill the plants, but does set them back for a while.  The Nature Conservancy’s Platte River Prairies, Nebraska.
I was mesmerized by the colors and patterns in the scorched cacti.
I was mesmerized by the colors and patterns in the scorched cacti.

I photographed scorched cacti for an embarrassingly long time.  Then, since my knees were already black with soot, I wandered around a little more and photographed a few other interesting post-burn scenes.  I’m a little eccentric that way.  Here are some of the other images from the day – enjoy your weekend!

Tall dropseed (Sporobolus compositus) on ashes.
Tall dropseed (Sporobolus compositus) on ashes.
Common mullein leaves, fuzzy and partially blackened by fire.
Common mullein (Verbascum thapsus) leaves, fuzzy and partially blackened by fire.
Partially burned seed pods of fourpoint evening primrose (Oenothera rhombipetala).
Partially burned seed pods of fourpoint evening primrose (Oenothera rhombipetala).
The remains of a milkweed pod (Asclepias syriaca).
The remains of a milkweed pod (Asclepias syriaca).