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Aberdeen MS | The "sample where you are going to plant" is a good method and will give you the best available data to work off of.
When I sampled and got into a ridge till field, I sampled part way down the ridge at a downward angle toward the middle of the ridge. That method gave pretty accurate results. It stayed out of the concentrated band and brought a little dirt that was going to be moved into the sample.
On the subject of "cutting rates" and having the soil still survive, I'll give it my best shot as to how George is/may be looking at things.
What is being used as a base application rate is the broadcast build recs that are computer generated off of the resulting soil test reports. That nutrient application recommendation will vary from field to field, area to area, soil type to soil type, I don't think any of us will disagree on that. But IMO, that process is kind of like a computer generated weather forecast. And another thing we need to keep in mind, those numbers were initially set up for dealers to have a tool to sell product, but we have accepted them for so long we take them as "truth" from an agronomic standpoint.
Where the reduction comes into play will also vary. Soil type, management practice, nutrient type (to a degree), and soil profile is what will determine how much reduction can be applied.
How many growers are applying removal rates only already, and seeing no drop in yield? Quite a few, applying removal vs build is already an accepted practice. You have just accomplished the first step in a % of reduction that has been a proven practice. So far, I think we can all agree we haven't "harmed" our soils at this point. We may not have improved them any, but we haven't harmed them either.
I don't think any of us will dispute what Mr Wilson finds for his soils and what he has documented on his practices. To a point, that theory works and applies to soils in quite a number of different areas, almost to all areas of ag production...... in varying degrees.
I know for a fact here in MN in my area, anywhere from 60 - 80 bu/ac corn can be grown without putting any additional nutrients down for the coming crop ( one of my neighbors used to grow 135 bu corn with 80# of N broadcast and us putting down a 20 - 28 - 0 in a 2 X 2 starter band at planting only). I don't think we can dispute the fact that the soil will grow something in some amount without additional "help" from us. Our lawns do it yearly and do it quite well, our road ditches grow quite well, the CRP ground keeps the cover crop relatively healthy with no nutrients added. Before man started tilling the earth, the plains had a "crop" the grew year after year after year.
To what degree can your soil sustain a crop with no intervention from us? That is going to be highly variable across the nation. That's where George's "might" comes into play when referring to a 20 - 50% reduction in applied nutrients IMO ( I can't speak for him, but I know at one point, he used to monitor this board because he asked me for the link to get here). No tillers and strip tillers SHOULD be increasing what the soil can do on it's own by leaving the residue on top, allowing earth worms to do their thing, and letting the residue return to soil OM naturally. The build up of OM/amount of OM is what is going to determine what the soil can do on it's own. If OM wasn't that important, some of you guys wouldn't be striving so hard to build it up. It's more important than some are willing to realize.
To my knowledge, the Universities and soil labs have NEVER taken into account the soil's ability to sustain a crop into account when offering their recommendations. So, in my mind, even though one has cut back to replacing removal amounts only, it is still a "build" nutrient program to a point.
I know that the U of Mn has done tests on the effects of banding nutrients and the effective results of the practice, I don't have my fingers on the data, but a few email's would get me the power point presentation and data sheets explaining the process as researched. What was found and determined was in a nutshell this.
When banding in a high enough amount, one super saturates the band area, reducing the amount of nutrient tie up that occurs naturally. That leaves more of applied nutrient available for the growing crop with less "pull" from the "soil bank" ....... to a point. Yes, one might be "shorting" the area from between the row in a row crop situation, but the corn or bean isn't growing 15" from the row, the weeds are. With no tilling/strip tilling where you can control where the next crop will be planted, you can achieve this with year after year repeatability. With the reduced amount of drawing nutrients from the "soil bank" and relying more heavily on the applied nutrient, we have "built" the nutrient base of the soil. As one moves over from year to year in planting/stripping. You now super saturate the soil structure with "held" nutrients "broad spectrum" to a point. The amounts, IMO, is what the ongoing research data is yet to show, but it's a start. But I do know it's a long term process, not a year to year occurance with immediate cause and effect.
As Mr Wilson reports, after application year, a % is released in each subsequent year after that for crop use. As long as one is taking a % of something, you will never achieve 0. So in effect, some of the high dollar nutrients put down this year, will stay in the soil never to return for an economic gain. Also though along this line of thought, there is a point that requirements will be greater than the amount that is available. Here again is where the "May/Might" comes into play from the reported finding to date.
For those willing to take on the higher level of management this process requires, it can and will pay off hugely to the net profit over the long run of an operation. NT/ST growers have already realized a higher level of management is needed, this is just another step/process in the program/system. What type of management program will be needed will vary from field to field across the US for the reasons stated above.
It may be a once in a 5 yr heavier broadcast application for some soil types.... a further reduction for others. You CANNOT paint this method with a broad brush.
I'd like to think the majority of growers would be willing to take on the higher needed management to apply this practice for economic gain, but in reality I'm afraid, there are still too many that want someone else to provide a Rx for them, so they can do the physical part of growing the crop, and then take full credit for the yields THEY produce. Those of you in consulting operations already know of way too many of those types.
Sorry for the "book", but I think what we need to do at this time, is not so much further the science, but utilize the gray matter between our ears, take a more common sense approach and look at what Mother Nature has done for far longer than we have, quit attempting to change her, and work WITH her. After all, 2 heads are better than one, and we for years have pushed the main "head" into the back ground.
I just hope this provides ideas and info for others to think about and study further on their own. | |
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How do you guys soil sample in strip till?
