Dan O. - Nitrogen Tied up
08-20-2003, 09:23 PM
#1
Nontypical Buck
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Join Date: Feb 2003
Location: cazenovia, NY USA
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Dan O. - Nitrogen Tied up
Dan O.
- Once specifically, you mentioned that Corn was difficult to " break down" and the more Nitrogen in the soil, helped to break it down. What is the mechanism for this - can added N, help release minerals from previous residue? If not what can be done?
I assume that Nitrogen (probably large amounts) is tied up in the stalks tilled back into the ground, I know it can be with Rye when its cut after its gone dry. Will Clover' s production of Nitrogen help to more quickly break down residue to free up Nitrogen (Ca, P & K also)??
Sorry for the Techincal question - I thought you might know.
Thanks
Sean Malloy
- Once specifically, you mentioned that Corn was difficult to " break down" and the more Nitrogen in the soil, helped to break it down. What is the mechanism for this - can added N, help release minerals from previous residue? If not what can be done?
I assume that Nitrogen (probably large amounts) is tied up in the stalks tilled back into the ground, I know it can be with Rye when its cut after its gone dry. Will Clover' s production of Nitrogen help to more quickly break down residue to free up Nitrogen (Ca, P & K also)??
Sorry for the Techincal question - I thought you might know.
Thanks
Sean Malloy
08-21-2003, 07:21 AM
#2
Join Date: May 2003
Location: Western MO
Posts: 321
RE: Dan O. - Nitrogen Tied up
Farm.....makes me want to put on my agronomy professor hat to try to explain this.. Do a google search on the " Nitorgen cycle" for more info.
Ill try to help this way. When the corn stalk is in the soil, it begins to decompose through a lot of processes...rotting basically from micobacterial efforts. As the stalk breaks down have niotrogen in the soil used or involved , thus some portion is " unavailable" to plants growing. But at tha same time, the " organic matter" componant, made up of broken down and fully digested material, will actually release its Nitrogen into the soil thus being available.
Adding N to the soil to speed breakdown of fodder will not work. The added N you put on will go through changes in form till its a nitrate, become water soluble, and leach out before it ever enhanses organic matter decomposition.
Focus your N applications on the " removal rates" of the crop you have planted. Think about a yard as a good example. applications for grass species should be in the 1 pound per 1000 square feet 2-3 times a year at most. If you have legumes as the primary plants, dont get all hung up on nitrogen.
Ill try to help this way. When the corn stalk is in the soil, it begins to decompose through a lot of processes...rotting basically from micobacterial efforts. As the stalk breaks down have niotrogen in the soil used or involved , thus some portion is " unavailable" to plants growing. But at tha same time, the " organic matter" componant, made up of broken down and fully digested material, will actually release its Nitrogen into the soil thus being available.
Adding N to the soil to speed breakdown of fodder will not work. The added N you put on will go through changes in form till its a nitrate, become water soluble, and leach out before it ever enhanses organic matter decomposition.
Focus your N applications on the " removal rates" of the crop you have planted. Think about a yard as a good example. applications for grass species should be in the 1 pound per 1000 square feet 2-3 times a year at most. If you have legumes as the primary plants, dont get all hung up on nitrogen.
08-21-2003, 07:42 AM
#3
Fork Horn
Join Date: Feb 2003
Location: Pound WI USA
Posts: 429
RE: Dan O. - Nitrogen Tied up
Farm Hunter, next year I am planting the acres that I had in corn the last two years into soybeans to try to help break down some of the residual stalks that plugged up my planter terribly last spring.
I plan to hit the plots with Round-up first and then plant RR beans.
Brian
I plan to hit the plots with Round-up first and then plant RR beans.
Brian
08-21-2003, 06:50 PM
#4
Nontypical Buck
Join Date: Feb 2003
Location: Ontario Canada
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RE: Dan O. - Nitrogen Tied up
farm hunter; corn doesn' t break down quickly because it has too high of an initial carbon:nitrogen ratio. Corn stocks are 60:1. Bacteria normally require a 32:1 ratio for digestion of organic matter. Actually this based on 75% loss of carbon and a final ratio of 8:1. Yes; the nitrogen from your legumes will be consumed digesting corn stocks. The nitrogen will be freed up for further carbon decomposition or crop growth depending on the needs. The worst example of a high C:N ratio is sawdust. You require loads of nitrogen fertilizer just to keep the plants from showing nitrogen deficiency.
Wooddust; I' ve got to disagree with you on your statement. I used nitrogen sources to digest organic matter when I supervised a waste water treatment plant and my college soil textbooks recommend adding nitrogen for increasing the decomposition rate of corn stocks.
Dan O.
Wooddust; I' ve got to disagree with you on your statement. I used nitrogen sources to digest organic matter when I supervised a waste water treatment plant and my college soil textbooks recommend adding nitrogen for increasing the decomposition rate of corn stocks.
Dan O.
08-21-2003, 09:42 PM
#5
Nontypical Buck
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RE: Dan O. - Nitrogen Tied up
Dan -
I' ll bet you thought no one remembered that statement. I' ve been thinking about it since.
Let me just be clear - I think I understand - but I want to explain to the guys who hunt with me - WHY we need to move where we plant corn avery couple years.
Basically - This is Year 4 on our corn plot. Each year we leave it standing, and plow uder/brushog the stalks next spring. Understandably - each year we have to add more N ( also P&K ) to get a similar yeild. Now, can I assume that a good portion the N we put down, in year 5 is going to bacteria to break down previous years' corn litter in the soil? - And even less will end up available to the new corn plot? - I already know about Annual weed infestation - due to cultivation - I learned that one the hard way!!!
Would planting clover where corn was - " speed up" the breakdown of any corn residue? I see where farmers do this - sometimes - a rye/wheat/ or oats is planted before the legume.
What do you think- will that explanation help my cause to move the corn plots every 3-4 years??
Also thanks to Woodust and OSTDC for your comments -
I' ll bet you thought no one remembered that statement. I' ve been thinking about it since.
Let me just be clear - I think I understand - but I want to explain to the guys who hunt with me - WHY we need to move where we plant corn avery couple years.
Basically - This is Year 4 on our corn plot. Each year we leave it standing, and plow uder/brushog the stalks next spring. Understandably - each year we have to add more N ( also P&K ) to get a similar yeild. Now, can I assume that a good portion the N we put down, in year 5 is going to bacteria to break down previous years' corn litter in the soil? - And even less will end up available to the new corn plot? - I already know about Annual weed infestation - due to cultivation - I learned that one the hard way!!!
Would planting clover where corn was - " speed up" the breakdown of any corn residue? I see where farmers do this - sometimes - a rye/wheat/ or oats is planted before the legume.
What do you think- will that explanation help my cause to move the corn plots every 3-4 years??
Also thanks to Woodust and OSTDC for your comments -
08-22-2003, 03:07 PM
#6
Nontypical Buck
Join Date: Feb 2003
Location: Ontario Canada
Posts: 2,059
RE: Dan O. - Nitrogen Tied up
farm hunter; remember that you don' t lose the nitrogen, you just tie it up to create proteins, etc in the bacteria that are feeding on the corn stalks. The corn litter is actually very good for the soil as organic matter. Some of it breaks down to humus which decomposes very slowly and improves soil tilth. If you can keep the weeds under control and keep your addition of nitrogen up, you can grow corn continuously. If you didn' t add enough nitrogen the yields would drop off quickly. I' ve heard about some corn farmers who return their crop residue to the ground and have raised their soil organic matter to virgin levels.
Usually the farmers plant the legume before the crop that needs the nitrogen. In order to utilize the nitrogen in the legume the legume has to be decomposed (sacrificed).
This may not be the answer that you' re looking for. You will reach a constant level of fertilizer requirements when the nitrogen that the bacteria contain that are decomposing the corn stalks equals the carbon needs in the new corn stocks being added each year in a ratio of 1:32 (before digestion).
Rotation of crops is good for reasons other than fertilization. Different weeds grow with different crops. A good rotation will break the weed cycle. Different crops use different fertilizer elements more efficiently. Different crops have different diseases.
Dan O.
Usually the farmers plant the legume before the crop that needs the nitrogen. In order to utilize the nitrogen in the legume the legume has to be decomposed (sacrificed).
This may not be the answer that you' re looking for. You will reach a constant level of fertilizer requirements when the nitrogen that the bacteria contain that are decomposing the corn stalks equals the carbon needs in the new corn stocks being added each year in a ratio of 1:32 (before digestion).
Rotation of crops is good for reasons other than fertilization. Different weeds grow with different crops. A good rotation will break the weed cycle. Different crops use different fertilizer elements more efficiently. Different crops have different diseases.
Dan O.
08-22-2003, 10:13 PM
#7
Nontypical Buck
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RE: Dan O. - Nitrogen Tied up
Dan - Thanks ............your answer was very good, and helps me look in the right places for the correct information - I appreciate you taking the time.
08-23-2003, 10:44 AM
#8
Nontypical Buck
Join Date: Feb 2003
Location: Ontario Canada
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RE: Dan O. - Nitrogen Tied up
farm hunter; if you can get a book called: Soils and Soil Fertility, by Thompson & Troeh, published by McGraw Hill; it would be worth the money. Thompson and Troeh were profs at Iowa State University. This book makes you look at dirt differently
Dan O.
Dan O.
08-24-2003, 08:00 AM
#9
Join Date: May 2003
Location: Western MO
Posts: 321
RE: Dan O. - Nitrogen Tied up
Dan, we disagree at all, its the circumstance that we are coming from. If you are talking about adding nitrogen in a composting situation, it will speed the reaction to a degree if we have the right balance of Green to brown material and moisture, and if we keep the reactions going by turning.
But in a field situation, adding nitrogen to speed the breakdown of organic material like a corn stalks will only add a very marginal amount of activity. The reason is that the Nitrogen rapidly goes through the changes from nitrite to nitrate and in the last stages of the reaction it becomes water soluable and will be gone from the soil profile rapidly as it leaches out or moves into a gas form. Addind additional nitrogen beyond the needs of the plants you are growing is a very expensive and ecologically poor idea.
One role of the previous crop residue is to help maintain or improve tilth and aid soil permeability. Residue can be a very good thing. It slows erosion, aids soil health from a bacterial standpoint, and does not interfere with next crops at all.
To speed the decomposition, the best thing to do is to chop the residue as small as possible, increasing the surface ara exposed to moisture, bacteria and soil. This will do more than anything.
But in a field situation, adding nitrogen to speed the breakdown of organic material like a corn stalks will only add a very marginal amount of activity. The reason is that the Nitrogen rapidly goes through the changes from nitrite to nitrate and in the last stages of the reaction it becomes water soluable and will be gone from the soil profile rapidly as it leaches out or moves into a gas form. Addind additional nitrogen beyond the needs of the plants you are growing is a very expensive and ecologically poor idea.
One role of the previous crop residue is to help maintain or improve tilth and aid soil permeability. Residue can be a very good thing. It slows erosion, aids soil health from a bacterial standpoint, and does not interfere with next crops at all.
To speed the decomposition, the best thing to do is to chop the residue as small as possible, increasing the surface ara exposed to moisture, bacteria and soil. This will do more than anything.
08-24-2003, 12:32 PM
#10
Nontypical Buck
Join Date: Feb 2003
Location: Ontario Canada
Posts: 2,059
RE: Dan O. - Nitrogen Tied up
Wooddust; I agree with your statements for chopping the residue and the positive organic matter effect on tilth. As for nitrogen addition you may not understand what I mean by additional nitrogen.
Please read this statement and see where I' m coming from. Soils release a certain amount of nitrogen as organic matter decomposes. This is greater in virgin soils and less in soils that have been under cultivation for some time. Crop nitrogen addition rate recommendations are based on the crop requirements minus the natural release. If a large amount of low nitrogen organic matter is added to the soil, bacteria will tie-up or immobilize a portion of that available nitrogen. If additional nitrogen has been added for a crop, say 100 lb./acre, and the amount of nitrogen released by the soil is inadequite for bacterial growth, the bacteria will use part of the released nitrogen for decomposition purposes. In order to prevent the planted crop from being nitrogen deficient additional nitrogen should be added to make up for the soil nitrogen immobilized by bacteria during the organic matter decomposition. This effect is the worst in soils that have low organic matter and low fertility. The effect lessens as the organic matter is converted to humus and a slower decomposition rate takes over. The situation also improves with time as the soil organic matter and annual nitrogen release increase (if continual organic matter additions are made).
If farm hunter first planted his corn on a field that hadn' t been worked for a long time the cultivation would have sped up nitrogen release to a high rate. This would drop off over a few years and increasing amounts of nitrogen would be required. This could be the cause of his increasing nitrogen needs. If the field had been cultivated for a long time and was in a poor state of fertility, nitrogen immobilization is very possible.
Organic matter decomposition releases ammonia nitrogen, not nitrites or nitrates. Most ammonia is adsorbed on soil cation-exchange sites. Further microbial action is required to go through the nitrite-nitrate conversions. Even at that point the only main loses with be by leaching. It takes a further anearobic digestion to produce nitrogen gas and this requires wet soil. In my area the average soil temperatures of 40-50 degrees prevent these reactions except during the active plant growing season.
Any excess nitrogen that is produced from the organic matter digestion in farm hunters case would be tied up as long term storage as humus or on cation-exchange sites. This nitrogen would then help to prevent nitrogen immobilization the following year (to digest this years organic matter).
I agree that excess fertilizer additions are evirinmently and economically unsound. There is another way to prevent the problem of immobilization, work the organic matter into the soil (with or without fertilizer), delay planting 3-4 weeks with the fertilizer, or 6-8 weeks without. When the fertilizer application is made for the crop subtract the fertilizer that was added for decomposition. Unfortunately the immobilization will take place again the following year if you try to plant into heavy crop residues. Another method is to rotate the crops as farm hunter suggests and plant a legume (low nitrogen requirements).
Dan O.
Please read this statement and see where I' m coming from. Soils release a certain amount of nitrogen as organic matter decomposes. This is greater in virgin soils and less in soils that have been under cultivation for some time. Crop nitrogen addition rate recommendations are based on the crop requirements minus the natural release. If a large amount of low nitrogen organic matter is added to the soil, bacteria will tie-up or immobilize a portion of that available nitrogen. If additional nitrogen has been added for a crop, say 100 lb./acre, and the amount of nitrogen released by the soil is inadequite for bacterial growth, the bacteria will use part of the released nitrogen for decomposition purposes. In order to prevent the planted crop from being nitrogen deficient additional nitrogen should be added to make up for the soil nitrogen immobilized by bacteria during the organic matter decomposition. This effect is the worst in soils that have low organic matter and low fertility. The effect lessens as the organic matter is converted to humus and a slower decomposition rate takes over. The situation also improves with time as the soil organic matter and annual nitrogen release increase (if continual organic matter additions are made).
If farm hunter first planted his corn on a field that hadn' t been worked for a long time the cultivation would have sped up nitrogen release to a high rate. This would drop off over a few years and increasing amounts of nitrogen would be required. This could be the cause of his increasing nitrogen needs. If the field had been cultivated for a long time and was in a poor state of fertility, nitrogen immobilization is very possible.
Organic matter decomposition releases ammonia nitrogen, not nitrites or nitrates. Most ammonia is adsorbed on soil cation-exchange sites. Further microbial action is required to go through the nitrite-nitrate conversions. Even at that point the only main loses with be by leaching. It takes a further anearobic digestion to produce nitrogen gas and this requires wet soil. In my area the average soil temperatures of 40-50 degrees prevent these reactions except during the active plant growing season.
Any excess nitrogen that is produced from the organic matter digestion in farm hunters case would be tied up as long term storage as humus or on cation-exchange sites. This nitrogen would then help to prevent nitrogen immobilization the following year (to digest this years organic matter).
I agree that excess fertilizer additions are evirinmently and economically unsound. There is another way to prevent the problem of immobilization, work the organic matter into the soil (with or without fertilizer), delay planting 3-4 weeks with the fertilizer, or 6-8 weeks without. When the fertilizer application is made for the crop subtract the fertilizer that was added for decomposition. Unfortunately the immobilization will take place again the following year if you try to plant into heavy crop residues. Another method is to rotate the crops as farm hunter suggests and plant a legume (low nitrogen requirements).
Dan O.