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Discussion Starter #1
A few yrs ago I posted a thread saying the nitrogen calculations didn't reflect my yield. Some said mineralization of old residue was the difference.

Here I am again. Used the same blend, with 80lbs N (60%ESN), seeded 2.5lbs, 3.5 in spread tips old junky 5710. Canola stubble so basically sticks.

Using a rule of thumb 1.5-2 lbs N per bu yield, this field shouldn't have made more than 50bu and more likely under that. Mineralization of canola straw accounts for extra 10 bu in yield???
 

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you are just taking it out of the land, the excess over the applied nitrogen .. the land [without fertilizer] does have an effect by itself ... do it often enough and it reduces the nutrients in the land itself ..
 

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we had excellent durum yields too.... and for some reason the canola out yielded the pulse stubble this year. not the first time that has happened, usually when a little on the moist / cool side. likely disease suppression?


we were really on the cool humid side through first 20 days of July..... Im going with much more efficient flowering / fertilization of the heads than usual!!!!
 

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and improving soil biology / organic matter..... it seems like every above average year for rainfall our yields beat the last "good" year, some really interesting things going on under the surface I think.
 

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Also, we had an insane amount of thunderstorms with a lot of lightning. I've always been told that contributes several pounds of N per growing season.
 

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When you get a dry spring you have a much larger root system, which in turn scavenged for nutrients much better once the rains started to fall. You are depleting N from a much deeper part of the soil profile and possibly extracting from depths that roots don't normally get to in wetter years.
 

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Rain is part of the nitrogen cycle. Something to be learnt here about timing of nitrogen, during the whole growing cycle. Lightning fixes nitrogen in the atmosphere. Also the rain near large cities have high fixed nitrogen from vehicle exhaust from city smog.
Would that be something that the higher levels of CO2 in the atmosphere was helping, NASA did say that satellite pictures shows that the planet earth as never been greener from all the extra CO2.
A part of me wishes, that even though we are at 400 PPM of CO2, that at 450 plus some unknown evolutionary ancient gene would kick in, and plants started to fix their own nitrogen. Mother nature gives the fertilizer monopoly creeps the big middle finger. I actually dream about that, (Deep thoughts by Combine Pilot).
 

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Discussion Starter #11
I didn't test last fall but there was a 54bu canola crop come off there with 100# N used so that is right in line with my yield expectations. I don't think there was any residual N left over. I don't broadcast or overapply. Everything is in the seed row so I am assume like almost all is taken up over the season.
 

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I didn't test last fall but there was a 54bu canola crop come off there with 100# N used so that is right in line with my yield expectations. I don't think there was any residual N left over. I don't broadcast or overapply. Everything is in the seed row so I am assume like almost all is taken up over the season.
You don't know if there was any residual N left from previous years either. You need to soil test or you are just guessing.
 

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You can't judge a crop by only what you put in for fertilizer. Soil health, and as stated earlier lightening strikes, break down of nutrients etc all add to crop health. Your canola the yr before might have did some work for you. It is deep rooted and may have brought up nutrients from far below the surface. Not all the fertilizer goes into the seed itself. A lot is retained in the decaying roots and plant matter as you know. I don't believe soil tests always. A spade will tell you a lot as well.
 

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A 54 bushel/acre canola crop will have 94.5# of n in the seed 53.5# of n in the stover 147# total . a 60 bushel wheat crop will use 89# n in the grain and 42# in the stover. 131# total. Then there is carbon to nitrogen ratio for the rate of stover break down.
 

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OM release of nutrients will vary on the year, rainfall, temperature, timing. It's amazing what rain at the right time will do. pH of rain makes it better than irrigation water.

Took a little bit to find this. NADP switched universities since I looked at the maps last. Some of the N comes from lightning but most comes from emissions from vehicles or livestock.

I'm guessing Canada has maps like this available too. Here is the link where I found them. They have quite a few different maps. I've attached NH4, total N, and total sulfur. Total Deposition Maps


nh4_ww-2017.png

n_tw-2017.png

s_tw-2017.png
 

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Rain is part of the nitrogen cycle. Something to be learnt here about timing of nitrogen, during the whole growing cycle. Lightning fixes nitrogen in the atmosphere. Also the rain near large cities have high fixed nitrogen from vehicle exhaust from city smog.
Would that be something that the higher levels of CO2 in the atmosphere was helping, NASA did say that satellite pictures shows that the planet earth as never been greener from all the extra CO2.
A part of me wishes, that even though we are at 400 PPM of CO2, that at 450 plus some unknown evolutionary ancient gene would kick in, and plants started to fix their own nitrogen. Mother nature gives the fertilizer monopoly creeps the big middle finger. I actually dream about that, (Deep thoughts by Combine Pilot).
I am with you on the Co2 theory Iam using less N than previous years and half the rain of normal and this year and last probably my best crops ever.
 
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