controlled burn

I googled "Effects of fire on rangeland soil biology" and got over a million results. Might try different variations of that. It'll keep you reading as long as you want.
 
Prairie Drifter said:
I'll dig some out of my files for you. For starters, google OSU patch burn. Lot of data there. Might also google KSU prescribed burns. Also plenty of videos on youtube about fire and prairie health.
Click to expand...

Thanks for the help. I was camping with the family this weekend and couldn't respond conveniently.
 
haymaker said:
Thank you, I am specificly interested in the effect of fire on the soil biology.
Click to expand...

From my reading I gather that species tolerant to fire have much deeper root systems. While it is certainly true that burning the top growth reduces that liter layer insects like, long term the profile is more active at deeper levels with the native species.

Once species are established burning doesn't need to occur often enough that soil biology is harmed.

'Course, I could be wrong.
 
I guess I don't know how soil biology would be harmed. Everything in nature is in constant change. A fire does many things to the soil and it's inhabitants, but so does weather, seasons, etc. There are chemical and physical aspects to the after-burn soil conditions. These may cause an immediate shift, but the nature of sod is that is swings back to a "normal" condition rapidly. As for fire tolerant species, there are also fire "dependent" species. Some of those are your most important forage producing species for cattle. Not including fire in your management scheme puts them at a disadvantage and will reduce them in the long-term. That will reduce your tonnage and forage quality.
 
That and also consider the aspect of a head fire vs. a backing fire. I chose to start running more of my burns because the local fire department and many other land managers that have a ton of acres to get done do not have the time to wait around and back fire a whole field.

A head fire does not bring as much heat to the soil as a back fire does. 2 different impacts.

Pure grass sod based soil does not seem to have to much biology going on compared with what a diversely designed stand and management can have.

Fire is one tool in an optimized landscape. Just ask mother Nature.
 
UGUIDE said:
That and also consider the aspect of a head fire vs. a backing fire. I chose to start running more of my burns because the local fire department and many other land managers that have a ton of acres to get done do not have the time to wait around and back fire a whole field.

A head fire does not bring as much heat to the soil as a back fire does. 2 different impacts.

Pure grass sod based soil does not seem to have to much biology going on compared with what a diversely designed stand and management can have.

Fire is one tool in an optimized landscape. Just ask mother Nature.
Click to expand...

We have interior ignition operations on almost all of our burns to help with backing and flanking. Running strips of fire into the wind helps us get these larger burns done in one burn period. A flanking fire has similar effects as a backing fire. Only the higher trained personnel are allowed to be interior during our fires. Most interior ignitions are done with an ATV driptorch. Various companies make them. If your interested I can send you some links.
 
I have been told that at 140 soil temp biology is dead. Most of the soil biology is near the top of the soil profile. I do not know how hot the soil gets from fire, I am sure it depends on many factors.
 
Most prescribed burns won't heat the soil more than 1/2 inch deep and often that layer isn't heated that much. The thatch tends to insulate it from the heat. It helps to have the soil profile wet. As Uguide mentioned, it is also less of an effect when you don't use a backfire. In that diversity drives natural systems, fire creating diversity in the plant community will enhance diversity in the soil biology as well.
 
Yesterday I spent some time with Ray Ward of Ward labs in Kearney Nebraska. He told me that biology is dead at 120 degrees. That means a black field on a hot summer day will kill a lot of biology. A few years ago I took a grazing course from Ian Mitchell Innes from South Africa, he mentioned something about fire and damage but I can't remember what he said. Wish I still had my memory.
 
Haymaker, I think you have to realize just how huge of a petrie dish our soil is, how resilient soil biota are, and just how many microbes and larger species are involved. We have farmers putting anhydrous ammonia on as fertilizer. That's a significant influence on soil life. Fire and native grass have been here together since those grasses first started evolving from their previous state. The Kansas Flint Hills have survived annual burning since the 80's. Any system you might put in place will not hold a candle to that. Further, if you look for non-native invaders in your stand, the % coverage of those should shock you more than any effect fire has temporarily on the soil community. Those life forms, just like the grasses themselves, evolved under fire and grazing.
 
Prairie Drifter said:
Haymaker, I think you have to realize just how huge of a petrie dish our soil is, how resilient soil biota are, and just how many microbes and larger species are involved. We have farmers putting anhydrous ammonia on as fertilizer. That's a significant influence on soil life. Fire and native grass have been here together since those grasses first started evolving from their previous state. The Kansas Flint Hills have survived annual burning since the 80's. Any system you might put in place will not hold a candle to that. Further, if you look for non-native invaders in your stand, the % coverage of those should shock you more than any effect fire has temporarily on the soil community. Those life forms, just like the grasses themselves, evolved under fire and grazing.
Click to expand...

Very well said PD. My soil biology concerns lies more within the farm ground in the Dakotas than the grasslands or ranch land. I see farm ground constantly tilled every year bringing up more salts every year further degrading the top soil. I have seen the production in one particular field diminish because of it. And now that same producer has installed drain tile to fix the problem. I am more worried about soybean fields laying black from September to June every year with no signs of life above ground except maybe some early Kocia every year. I am more worried about soil biology in the corn/bean rotation only and the lack of any small grains. I am more worried about soil biology with the constant chemical use. And lastly I am more worried about soil biology once the plow or wishek disk tills up that last remaining chunk of native prairie to chase the 7 dollar corn we once had and may never have again.

I realize there is a push to address some of these issues with cover crops and better education on chemical use and crop rotation but I consider that soil biology damage. Not a prescribed fire or even a wildfire for that matter.

And great conversation guys. This is one of the last great forums were real conversations can take place. Not just people taking jabs at each other.
 
Prairie Drifter said:
Haymaker, I think you have to realize just how huge of a petrie dish our soil is, how resilient soil biota are, and just how many microbes and larger species are involved. We have farmers putting anhydrous ammonia on as fertilizer. That's a significant influence on soil life. Fire and native grass have been here together since those grasses first started evolving from their previous state. The Kansas Flint Hills have survived annual burning since the 80's. Any system you might put in place will not hold a candle to that. Further, if you look for non-native invaders in your stand, the % coverage of those should shock you more than any effect fire has temporarily on the soil community. Those life forms, just like the grasses themselves, evolved under fire and grazing.
Click to expand...

You are right I do not realize how big a petrie dish our soil is. Nobody does, as I mentioned earlier I had the opportunity to hear and visit with Dr. Ray Ward who owns a lab that is the leader in this topic. He mentioned how much we do not know and I have heard the same from Dr. Mike Lehman who is a micro biologist at the ARS lab in Brookings South Dakota. There is so much we do not know, we need to learn. That is why I wondered if there is a PLFA test done before and after a burn, to learn. If we just look at the benefits we get the rose colored glasses effect.
 
3car said:
Very well said PD. My soil biology concerns lies more within the farm ground in the Dakotas than the grasslands or ranch land. I see farm ground constantly tilled every year bringing up more salts every year further degrading the top soil. I have seen the production in one particular field diminish because of it. And now that same producer has installed drain tile to fix the problem. I am more worried about soybean fields laying black from September to June every year with no signs of life above ground except maybe some early Kocia every year. I am more worried about soil biology in the corn/bean rotation only and the lack of any small grains. I am more worried about soil biology with the constant chemical use. And lastly I am more worried about soil biology once the plow or wishek disk tills up that last remaining chunk of native prairie to chase the 7 dollar corn we once had and may never have again.

I realize there is a push to address some of these issues with cover crops and better education on chemical use and crop rotation but I consider that soil biology damage. Not a prescribed fire or even a wildfire for that matter.

And great conversation guys. This is one of the last great forums were real conversations can take place. Not just people taking jabs at each other.
Click to expand...

I agree with every thing that you said. Our farm ground is degraded. We are still degrading it. So is our grass land but in different ways. We do not plant soybeans anymore. Roundup was patented as a herbicide and also as an antibiotic. So we put an antibiotic on land that we want more bacteria on, makes no sense. This is why we formed the South Dakota Soil Health Coalition. I am not saying there should never be a burn, but I want that burn to be a source of information so we really know as much as we can about the positives and negatives of that burn. Sometime when you are going to do a burn call me and I will come and pull the soil sample and send it to Ward lab and see what we can learn.
 
haymaker said:
I agree with every thing that you said. Our farm ground is degraded. We are still degrading it. So is our grass land but in different ways. We do not plant soybeans anymore. Roundup was patented as a herbicide and also as an antibiotic. So we put an antibiotic on land that we want more bacteria on, makes no sense. This is why we formed the South Dakota Soil Health Coalition. I am not saying there should never be a burn, but I want that burn to be a source of information so we really know as much as we can about the positives and negatives of that burn. Sometime when you are going to do a burn call me and I will come and pull the soil sample and send it to Ward lab and see what we can learn.
Click to expand...

lol, I was going to send you a text to see about the possibilities of that. I am for it and would like to learn more about the positive and negative effects of fire on soil biology.
 
haymaker said:
He told me that biology is dead at 120 degrees. That means a black field on a hot summer day will kill a lot of biology.
Click to expand...

I couldn't agree more. I have taken pictures of 4 corn fields the first week of June. 2 different neighbors both worked their fields black and planted corn in early May. Both are up about 2 feet. If you dug down in the soil you would feel it is very hot and dry the first 5-6 inches.

On my two adjacent fields my farmer planted corn the week after Memorial day and corn was 7" tall. Good cool moisture just below the wheat stubble/cover crop trash. Shelborne stripper header was used for harvest as well.

Last year my farmer took me around and showed off how amazing his no till "conventional" corn was compared to a host of adjacent GMO corn/soybean rotation corn. Theirs ran out of gas so to speak.

2 different systems. It's quite amazing.

The farmers time horizon outlook has a lot to do with it. Cron bean is short term outlook. Bean/Wheat/Cover Crop/Corn is the soil building long term high yielding outlook. Hope to have end of summer pics showing the comparison.

Side note: Prescribed fire are not impacting soil health as negatively as worked ground from AG. Prescribed fire is conservation. Worked ground is not. You can put your hand on the ground immediately after a head fire has gone through and it is cool to the touch.
 
Last edited:
haymaker said:
Yesterday I spent some time with Ray Ward of Ward labs in Kearney Nebraska. He told me that biology is dead at 120 degrees.
Click to expand...

I'm not quite understanding that statement, is he indicating the soil is void of biological life when it hits 120. Can you please expand on this? We have wild fires that sweep across our landscape at temps much higher then 120. In many cases these sites are greening up within few days to weeks. As these sites rejuvenate themselves growth is good as dead vegetative material has been converted to a more usable state, potash, and we tend to see higher biotic activity from insect, because of higher temps on these sites. What I have seen it is not so much the temp of the burn but the residence time of the fire. By this I mean how slow or fast a fire moves over the landscape. A cool fire with a long residence time is much more damaging to the area, think short flame lengths and taking 5 minutes to burn 20ft. Not all fires are created equal...

We see increased biotic activity in our clear cuts as a result in higher ambient temps because of timber removal and regeneration. Grouse, turkey and woodcock all utilize these area for their broods to acquire their needed protein for the chicks. These clearcuts are prescribe to mimic fire on the landscape. I know first hand these stands feel like temps are higher then 120. Some of our jack pine clearcuts become hot enough in the summer to open their pine cones which typically open by fire, so these temps do exceed 120.

Sorry for the rambling, just taken aback by that statement for Mr Ward. Course been 25 plus years since my soil biology classes and my memory is as good as it used to be.
 
You must log in or register to reply here.
Back
Top