The Pros and Cons of Burning the Prairie

(Jim) Hi, I’m Jim Shroyer, host of That’s My Farm and today we’re on the Rannells Flint Hills Prairie south of Manhattan. And we’re going to be talking to Dr. Clenton Owensby, a Range Scientist about the process of burning the prairie, the pros and cons and stay tuned, we’re going to see it.

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(Jim) Good morning folks, I’m Jim Shroyer the host of That’s My Farm and we’re in luck today because, one, we’re in Riley County, two, we’re on the Rannells Flint Hill Prairie and three, we have a renowned Range Scientist, Dr. Clenton Owensby and Clenton here has been on the forefront of burning management of the Flint Hills and Rangeland in Kansas. He has worked on, he actually pioneered the intensive early grazing program and one of my favorites is his work a number of years ago on elevated CO2 and its effect on plant composition of the rangeland. So, Clenton, you know if you’re a passerby through the Flint Hills in March and April you’re going to think it’s World War III, flames, the smoke, the scorched earth. So what is it about the Flint Hills and fire that go together? (Clenton) Well, the first thing about the prairie is rather simple and that is it wouldn’t be the prairie without this fire. There is a co-evolution of fire and these grasses and the grazers that were out here. So, in the initial development of this prairie you had fire, you had grazers and without those two things you then it disappeared. Initially, the burning occurred basically from lighting strikes. And then Native Americans also set a lot of fires. But then as European man settled this region they began to find that livestock could be contained with fire because they sought out those grazed areas and so they would burn a big patch of ground and they would know where their cattle were all the time. And then with the cattle drives that came from down in Texas after the Civil War and this area and the Flint Hills region of Kansas which is basically the only area around where burning occurs on a regular basis in the United States. So, what happened then was they found out if those steers that arrived here in the spring were on burned ground then they gained better. And so they took that as a pretty significant hint and began to do that as well. But naturally this prairie exists because the fire excludes pretty much invasion of woody species. And without fire, it’s going to go to a scrubbed woodland type, that’s basically… (Jim) Savannah type? (Clenton) Yeah, actually it’ll be closed canopy, it will be more like the Ozark region, closed completely. (Jim) Really? (Clenton) So the situation is, that without fire, you don’t have the Flint Hills. (Jim) So, how long has this been a prairie, how many years? (Clenton) Well basically, after the Wisconsin Age glaciers receded back about 30 thousand years ago, the climate changed over time until about 13,000 years ago this became a warm season perennial grass land type. (Jim) So before that timber? (Clenton) Timber. Yeah, there were trees here. (Jim) Well Clinton, hang on don’t go anywhere we’ve got to have a word from our sponsors and you at home don’t touch that dial.

(Jim) We have Dr. Clenton Owensby here and we’re going to continue talking about burning and rangeland. And so Clenton, basically how long have we been burning at K-State? (Clenton) Well K-State started the research work in burning probably late 1918-1919. And with some plots out on the old Casement pasture. Out there at Dan Casements place. But then formerly, when A.E. Aldis came they established these burning plots and ungrazed burning plots up north of the campus. (Jim) So they would just burn them but not graze them. (Clenton) Yeah. And that would have been 1926 and that ran until the horsey people ran me out. Which would have been 2003. The longest term burning research work actually in the world there. And what they were very prescient in their design of the initial work in that they looked at timing as when would you burn and what impact would those different times have? And that turned out to be really a very good approach to this. And so they continued those plots as I’ve said up until 2003. But in 1950 they decided that they would get a grazing area and Rougeler down in the Chase County area was in the Legislature and they passed a bill to buy an area for grazing research. One of the initial projects on there was grazing and burning at different times. And the upshot of that was that they found out very quickly that the cattle gained the best when you burned the prairie just as the warm season for new grasses began to grow. In addition to that, you had the most soil water and therefore you had the highest herbage yield. So the situation was that, and it maintained the highest quality grassland. So our research work in that area then told us that we had the opportunity to enhance productivity on the animal. Now we had another 40 years of research after that where we burned in the late spring and measured cattle gain. And the average over that period of time, was that a steer would gain about 32 pounds more. (Jim) Over the season? (Clenton) Over the season. But the interesting thing was that that also occurred only in the first two months of the season. (Jim) OK I see where we’re going with that. OK. We must take a break right now Clenton. Stay with us and folks at home don’t touch dial.

(Jim) Welcome back. We’re here with Dr. Clenton Owensby and let’s continue that thought process on that early gain after burning. (Clenton) Well basically what happens is that when you remove the litter from the surface of the soil, that soil begins to warm and when that soil begins to warm, then the microbial activity increases dramatically. And that then takes those nutrients that are in that old soil organic matter and releases them so the plants can begin to grow. And things like nitrogen and phosphorus, etc. (Jim) The cycles though, those cycles. (Clenton) Yeah. So what happens then is that those plants consume that, they take up whats ever there. They’re really greedy things. So, what you end up with, is that on the burned area you have a higher quality forage. And because it’s photo synthetically more active because it has a higher chlorophyll content because there’s more nitrogen, then it actually produces a more soluble carbohydrates for the animal to eat. All of that put together says that the forage quality is better. If it is a crude protein, it’s a higher digestibility and therefore the cattle will gain more. But as the plant matures it begins to take those nutrients that are in the above ground system and put them down below, so that they can use them for regrowth following the winter. So the quality begins to decline and that occurs around the middle of July. So, basically the advantage that you get due to burning in the improved gain is during that period prior to the movement of those nutrients down below the soil. (Jim) So, Clenton thank you for those comments and we have to take a break here. We’ll be right back.

(Jim) Welcome back, we’re here with Dr. Clenton Owensby talking about rangeland and burning. So Clenton, when is the best time to burn and what about frequency of burning? (Clenton) Well, all the research that we’ve done shows that we burn just at the beginning of growth of the warm season for new grasses in your region. So that would be earlier in the southern Flint Hills and later in the northern part of the Flint Hills. And so the reason for that is that you get the obvious best cattle gains. You get the best species composition as far as the grass is concerned. And lastly that is about the only time that you can kill woody species, sprouting woody species. (Jim) Because they are starting to bloom as well? (Clenton) Well, what they basically do, they have used all their nutrient resources, their food reserve and then you catch them at their low point in their food reserves and therefore you can kill them at that time. So timing is critical and should be done just at the beginning of growth at the warm season for new grasses. Now, frequency is another matter and that is if you’re a steer guy, if you’re out here, you only get the increase in gain during the year that you burn. So, you burn every year and it’s not going to cause any great change in the soil chemistry or whatever. It’s not going to degrade the system to do that. We would burn every year with a steer operation. The worst thing you can do is burn every other year, or burn every three years. (Jim) If you’re a stocker or anytime? (Clenton) Anytime. That’s the worst thing because what happens is you burn and you get the woody species when they are killed, the top is killed instead of having one killer come back, four will come back, so you increase the stand. In fact, over on the Kanza Prairie where they have done research work on the number of years interval with respect to burning, their greatest rate of increase in woody species was burning every four years. So, now the answer is, well is there a situation where you don’t have to burn? Well, it depends. If you’re a cow/calf operator it certainly, you don’t have to burn every year because you don’t really get a big boost in gain on those calves at that time because they’re not really functional ruminants until later in the season. (Jim) Exactly. (Clenton) So, you can get by with not burning for a period of time. My recommendation is simply that you not burn until maybe two to three years. And they you burn three years in a row. And then you go back if you want to not burn that particular year. So, the frequency with what you burn is dictated largely by whether you are a cow/calf or steer operator. Every year for the steers and you can skip years with a cow/calf operation. (Jim) But if you do skip you then want to follow it by two or three years of burning… (Clenton) Consecutively, absolutely. (Jim) To get rid of those woody species, invasive species… coming in. (Clenton) And things like the invasion of cool season grasses. (Jim) Right. Hey, thanks Clenton. Stay here, don’t move. And we’ll be right back and a word from our sponsors.

(Jim) Welcome back folks we have Dr. Clenton Owensby talking about burning and rangelands and Clenton so you did some…obviously you know you did the early work on intensive early grazing and so how does that fit in with burning? (Clenton) Well, the actual thing is, is that with intensive early stocking, you’re stocking only when the burning gives you an increase in gain, so that’s a really good feature in that regard. So, basically when we
introduce the intensive early stocking program into the Flint Hills, we jumped the average gain per acre from about 60 pounds to about 100 pounds simply because we were great grazing those cattle when we were getting the biggest increase in gain from both the forage quality, as well as the burning. (Jim) Because after, what did you say mid-July? (Clenton) Yeah. The gains go down, really badly. And so what basically has happened in the hills is that we have a fairly significant percentage of the Flint Hills are grazed intensive early. As a matter of fact, a guy told me the other day that runs trucks in this region, that they have a bigger demand for trucks in July than they do in October. (Jim) Taking them out. (Clenton) Taking them and out and so they go to the feedlot directly and there is an increase in feed efficiency in the feedlot, about a pound less feed per pound of gain simply because of when they finish in November as opposed to the cold months of January. So the hills are basically still a predominantly transient steer grazing area with the livestock moving out in the middle of July or in October to the feedlot directly. So that is the way the hills work and it’s a good thing. (Jim) It’s a good thing. So, Clenton you’ve told us a little bit about the advantages, what are some of the downsides? (Clenton) Well right now the biggest downside is the smoke that goes across the Kansas City or Wichita area. (Jim) Or even further. (Clenton) Yes, actually Lincoln has had some problems with that. Basically what happens is when you burn you create what are called low zone precursors and in the presence of sunlight that’s converted to ozone over these metropolitan areas and that’s a health risk for those people in those areas. Doesn’t matter quite frankly that they’re right up against the limit all the time but when we burn the Flint Hills, we add to that and it kicks it over. And so EPA said, “Hey, you will develop a smoke management plan.” And that smoke management plan won’t be a regulatory thing, it will be simply telling the ranchers when they should burn if they want to avoid putting this pollution problem across these areas. And so we’ve developed that and there’s a web site called that has a model that tells you for that particular day when you…where your smoke is going to go and whether it actually turns the counties red, that you shouldn’t burn on those days. And so it’s been a really good cooperative agreement arrangement between the ranching community and the EPA and the university system to develop this kind of a program so that burning can be maintained in the Flint Hills. (Jim) Well thanks Clenton, I really appreciate you taking time for us today. And we will see you all next week on That’s My Farm.

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