Thanks for the clarification. He also didn't seem too big on residue.. Did I interpret that wrong?
Ok I rewatched this. I have reached out to a PHD. Soil Scientist, I work with often, as I don't recognize much of what he is saying as facts. I am certain he is intelligent, however- there are certainly some questions I have.
1. The low pressure forcing N into the soil profile. I found this to be the opposite, as soils are more porous - the chance for ammonium to volatilize is higher. This makes sense, especially in freshly tilled fields that don't yet have active growth occurring.
2. He speaks about carbon leaving once a burndown is done with herbicide. However, he doesn't speak about CO2 leaving once tillage occurs. Of course, there is some carbon release when microbes consume thatch, that is why we have CO2 respiration tests. By having much of the consumption happen below ground, there is hope it's a slower release and that we can keep it in the soil.
3. He talks about nothing eating plants once GLY is used - I have not seen any peer-reviewed research that would echo this claim. Some research shows an increase in microbial activity - the issue is they are unsure if the pathogenic increase after that is higher vs. if/when GLY isn't used. This is highly debated and under research in academia.
4. He talks about nutrient stratification, specific to CA. He references CA leaching through the soil profile and getting outside the rhizosphere. This is interesting because one of the issues folks have with no-till is that the lime won't move through the soil profile, and we need to get it into the root zone. Now, many will just apply lime and give it time, hoping that through cover cropping and such you will alter the PH and movement of nutrients. However, in general, CA is not an overly mobile nutrient like say N.
My follow up to this would be
1. What are the manure inputs on these fields. Often folks will claim on N inputs but then we find out they are using 4 tons per acre of manure.
2. Without manure inputs, how is he increasing or even keeping OM the same - with tillage?
3. Has he done PLFA testing before and after on these fields to show an increase in fungi? If he is not seeing residue break down, specifically higher ligin filled, C:N ratio - that tells me that due to heavy tillage, he has little fungi in the soil, and the microbiome is heavily dominated by bacteria. Especially in the case where N is lacking the thatch will struggle to break down. This is KEY to understanding nutrient cycling and C:N ratios.
There is a ton to unpack here and I hope this doesn't come off as me being overly critical. Again, I think the gentleman is intelligent. However, I felt some of the points linked correlations and derived causations, and when that is happening on a large scale, without any locatable research to back it - I become curious to learn more.
Hope someone finds this useful.
