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Discussion Starter #1 (Edited)
So always worked under the assumption of about 2.5lbs of N per acre per bushel yield for most crops.

So for canola, 100# N should give 40 bu. Yet we grew 50 bu in 2016 and looks like we have more than 40 bu this yr.

In wheat, I used 75# N which should only give 30 bu, yet there is a crop closer to 45 bu coming. Last year we had 50 bu on the same blend.

On flax it seems to work. We used 70# N and have something in the mid 20 bu coming looks like, maybe higher.

The only thing I can think of is I am using 50-60% ESN in that blend and maybe it has a late season feeding effect or something. The lack of rain should have knocked these numbers down.

I was thinking of going up to 120# in canola, 100# in wheat and 80# in flax but we are getting pretty good bang for our buck at the current rates. Is this just a fluke?
 

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So always worked under the assumption of about 2.5lbs of N per acre per bushel yield for most crops.

So for canola, 100# N should give 40 bu. Yet we grew 50 bu in 2016 and looks like we have more than 40 bu this yr.

In wheat, I used 75# N which should only give 30 bu, yet there is a crop closer to 45 bu coming. Last year we had 50 bu on the same blend.

On flax it seems to work. We used 70# N and have something in the mid 20 bu coming looks like, maybe higher.

The only thing I can think of is I am using 50-60% ESN in that blend and maybe it has a late season feeding effect or something. The lack of rain should have knocked these numbers down.

I was thinking of going up to 120# in canola, 100# in wheat and 80# in flax but we are getting pretty good bang for our buck at the current rates. Is this just a fluke?

don't forget about residual N in soil, plus whatever comes from organic matter. N is not just what you apply...
 

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Hmph. Always work on ~1.2-1.5 lb. N per bushel for both corn and wheat around here, and it seems to work. Rarely get retained N in soil, or just consider it a bonus, unless plowing down a great alfalfa stand or something, which I would never do....Interesting topic.
 

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As discussed above you need to account for N in the soil in the nitrate and ammonium forms as well as the N that can be released in your organic matter (that will depend on moisture and how healthy your soil is, is it bacterial dominant or does it have a diverse ecology), and finally on the N fixing microbes in your soil. From our experience if you use synthetic fertilizers and place them with the seed, side band, etc, your plants will need to rely more on what you are providing and less will be provided by the soil through the organic matter and microbes. Therefore you will need to use more synthetic fertilizers as you continue to farm, I have yet to hear of anyone doing this and being able to reduce their use and increase their crop yields. My opinion if you broadcast your fert or use a mid row band (still a hot source once the roots find it and then will become lazy) you are making the root system grow out and find nutrients and as such will promote a symbiotic relationship with the microbes in the soil. They will exchange nutrients for sugars from the roots, thereby pushing carbon into the soil. This is the most effective way of building organic matter, not growing lots of top growth but fostering root microbe interaction.

So in a long about way I can easily believe you can get those yields with the rates you are saying, just not sure it will sustain depending on your farming practices.
 

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Many things affect crop yield and only one of them is N. Then the things that affect N include residual/applied/organic matter/ph/etc.

Have you soil tested these fields annually with GPS referenced samples? If not then you are really kind of guessing. If you are unable or unwilling to do that then simply applying removal rates each year and maybe adjusting for loss from adverse weather is probably the next best approach.

Those removal charts are usually pretty accurate.
 

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The numbers should only be used to set you on the right track. Too many variables beyond that. The largest being moisture, temperature, CEC, and residual.

I have always been told 1unit/bu in corn and 2unit/bu in wheat, but have grown 200bu corn on 0.8 and 100bu wheat on 1.2. Now this is not the norm. It was largely aided by mild temps and late season soft rains when needed. The early rains or heat will exhaust much more of your N than you realise. I wouldnt be surprised if we are putting down double what we truly need, and we are just that inefficient.

The ESN i think is showing you a little of that in this scenario. Thats the whole purpose of it. Its the only delayed release that ive found works at all, and it still isnt a slow release like they claim, but it can be delayed depending on your weather, which is very beneficial.
 

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I use N in wheat for yield and protein. For DNS I use 3.3-3.5lbs per bushel for 14% pro. I can get higher yield but protein drops. Lower yield and protein goes up. This is available N. Applied and what is already there. If things are way out of wack, these numbers may not work. Variety also changes things a bit. Rule of thumb for me here.

Canola? Yield and energy in the seed? Does it effect oil content? I know nothing about canola.
 

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Many things affect crop yield and only one of them is N. Then the things that affect N include residual/applied/organic matter/ph/etc.

Have you soil tested these fields annually with GPS referenced samples? If not then you are really kind of guessing. If you are unable or unwilling to do that then simply applying removal rates each year and maybe adjusting for loss from adverse weather is probably the next best approach.

Those removal charts are usually pretty accurate.
I agree.
Soil sample yearly with GPS reference and adjust fertility accordingly.
During the wet years in our area we were draining the soil nutrients and were increasing fertilizer load accordingly. Now with 3 out of 4 years drought with close to the same fertilizer applied our nutrient levels are going back up.
 

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Fertilizing flax is a bit of a lottery plus I’ve ever grown it, I just used the same blend for wheat and canola, the protein premium in wheat often covered the entire fertilizer bill for it.
Probably wouldn’t in the era of fertilizer extortionists though.
 

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Need to take into account the N that is available in your soil, as well as the N that will be released through mineralization throughout the growing season. There are an incredible number of variables involved in what you'll get from mineralization, but I believe the biggest influencer is the organic matter content of your soil.
 

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Discussion Starter #14 (Edited)
The mineralization cant account for that much N, especially I havent had wheat in the rotation for 5 yrs. Canola is just sticks and flax straw we bunch and burn. Had pulses on some of that land like 3 yrs ago - cant still be N from those crops in the soil.

Some of the land was tilled in 2015 to recover sloughs and wet spots that finally dried out.

I want to be careful not to mine the land. I could get a nasty surprise using the same blends and then boom, the yields drop. Been a while since I soil tested.
 

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I wouldnt worry about mining N. That part you can always get a quick easy response. Id only worry about the PKS. Soil sample annually.
 

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The odd time i soil sample it basically tells me to quit wasting my time and sell the farm, but i ignore it and i am still here.
 

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Like everything else on this forum, it foolish to think there a one size fit all fertilizer recommendation that works in all areas, crops, and conditions. Unfortunately, think there still plenty of farmers that do not understand fertilizer analysis and/or soil samples. Farming is a business where usually the people that teach people, who do not understand things, are the ones selling products that the farmer "needs". On top of this really think fertilizer is an area where there could even be things that the experts do not understand. I have played around with very high rates of fertilizer(not nearly as extreme as SWMan stories) and relatively low rates and still really have no consistent rates that use for each crop/year. I base fertilizer on budget(fertilizer cost, crop selection, conditions, insurance coverage), but have maximum levels that will not go over. Going forward I think there are going to be many different fertilizer options so not too anxious about my fertilizer "bank".
 

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Here's a bat sh!t crazy theory:
We know that plants will produce specific exudates to foster specific classes of biology, that in turn "mine" and help feed the plant the nutrient it is lacking that caused the plant to need to produce the exudate. So if this happens in the soil, why can't it happen above ground?

Our atmosphere is 78% Nitrogen, that's a pretty rich environment. So if the plant, due to conducive environmental conditions, has the potential to produce more yield than we originally planned for, might be running short on N. So as long as we have the micro nutrients in place to fire the enzymatic processes to produce exudates and metabolites, who's to say the plant doesn't create a leaf surface environment for organisms like azotabacter that "mine" N out of thin air and feed it to the plant? If that's the case, couldn't we apply microbes like azotabacter to the crop, along with a food source to propagate a population of N "mining" microbes on the leaf surface, and possibly reduce our commercial N inputs?:biggrin:
 

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Here's a bat sh!t crazy theory:
We know that plants will produce specific exudates to foster specific classes of biology, that in turn "mine" and help feed the plant the nutrient it is lacking that caused the plant to need to produce the exudate. So if this happens in the soil, why can't it happen above ground?

Our atmosphere is 78% Nitrogen, that's a pretty rich environment. So if the plant, due to conducive environmental conditions, has the potential to produce more yield than we originally planned for, might be running short on N. So as long as we have the micro nutrients in place to fire the enzymatic processes to produce exudates and metabolites, who's to say the plant doesn't create a leaf surface environment for organisms like azotabacter that "mine" N out of thin air and feed it to the plant? If that's the case, couldn't we apply microbes like azotabacter to the crop, along with a food source to propagate a population of N "mining" microbes on the leaf surface, and possibly reduce our commercial N inputs?:biggrin:
That is what the inoculant N-fix is trying to do. i have been watching for commercialization of their inoculant, which pulls N right out of the atmosphere and fixes it. it was discovered in sugar cane. apparently can be used on all cereals and oilseeds, a game changer if it ever comes to fruition. But, i am not holding my breath, word on other forums is it is a pipe dream a decade away.

N-Fix » Natural nitrogen to boost agriculture
 
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