You can’t bio-product your way to soil health—products don’t improve soil’s physical conditions, but proven practices do. Before spending your money on an unproven product, try a time-tested practice to build soil. My latest:
The idea that biodiversity drives ecosystem function is deeply engrained in ecology, and has been applied to agriculture. A rigorous analysis of causation vs. correlation challenges this: "there is no causal relationship found between biodiversity and ecosystem functioning."
Increasing soil organic matter is difficult. How difficult?
Here are the numbers:
To increase SOM 1%➡️1.1% (=11 tons in top 6"), with 1%/yr loss, requires ~6.7 tons/ac biomass = 223 corn or 239 bu/ac wheat crops.
See my calculations, do your own...
How NOT to publicize your research.
Both the tweet and the paper could have easily stated: "Surfactants, NOT glyphosate, cause high levels of mortality following contact exposure in bumble bees."
And highlight this: "This wasn't meant to be 'field realistic' for agriculture"
True story: legumes fix nitrogen
Based on a true story: legume crops never need fertilizer
Inspired by a true story: we can replace all fertilizers with soil biology
As seen in the tweet below, many people believe if we just mix crops to the field to get away from monoculture (1 species), yields increase.
This is NOT true. A farmer produces more food by growing only wheat without walnuts.
Let's add some context and nuance to this.
Does synthetic nitrogen fertilizer burn up soil organic matter?
Multiple studies say NO.
N fertilizer actually slows loss of old soil organic matter and increases microbial biomass and new soil organic matter.
New from
@jwadeexperience
and I:
"The truth that agriculture consumes 6% of the world’s fossil fuel energy" should not be something to deplore. It is, rather, quite impressive that we can feed 8.1 billion people on only 6%, and this too will improve.
"Awash in fossil fuel" 🙄
= Whining of well-fed activists.
Most American farms consume massive amounts of oil and gas. As the climate crisis intensifies, lawmakers must start regulating the industry and holding it accountable for its impact on the air and water.
#oped
by
@p_lehner
So, if N fertilizer increases soil organic matter in the long-term, does it have a similar effect on microbial biomass?
This review says YES, N fertilizer application "led to a 15.1% increase in the microbial biomass above unfertilized controls."
Does synthetic nitrogen fertilizer burn up soil organic matter?
Multiple studies say NO.
N fertilizer actually slows loss of old soil organic matter and increases microbial biomass and new soil organic matter.
New from
@jwadeexperience
and I:
How often have you heard, "Farming decreases soil biodiveristy"?
Research finds across Europe: "HIGHER diversity of fungi, protists, nematodes, arthropods, and annelids was observed in croplands than in less intensively managed systems"
Nice article on short corn. Benefits:
•Better wind resistance
•Later season access to field, fertilizer application, etc.
•More roots?
•Higher yields?
More or less crop residue?
Do you think microbes in your manure, compost, or in their extracts, will help your soil? Think again.
They often don’t adapt well to the soil’s habitats and don’t compete well with native microbes. My latest...
Surprise of 2023:
Cropland soils found to have higher diversity of fungi, protists, nematodes, and arthropods than grasslands and woodlands.
And related: soil biodiversity is not tightly linked to plant biodiversity.
Open access.
When people invented agriculture, they asked, "What can we change in nature to get more food?"
Now in agriculture, farm-like-nature people ask, "What can we change in agriculture to make it more like nature?"
The most common result of doing the latter: less food.
"We need to build up soil organic matter so we can reduce our reliance on fertilizer" makes little sense.
Building organic matter requires nutrients. You can't get nutrients out of the soil that you don't put in unless you want to mine it.
Open access.
More research on glyphosate impacts on soil microbiology: neither soil bacteria and fungal diversity (alpha and beta) nor functional potential were impacted by cumulative glyphosate doses.
New long-term research: the benefit of no-till practices on water infiltration is large. Unlike tilled soil, where aggregates break down after the first rain or irrigation, no-till methods maintain soil structure and infiltration effectively.
Open access
It's scary how many intelligent people believe we rely on N fertilizer because our soils are degraded and not because we need to replace the N that is removed every year to feed people.
Yes, we can become better at using N fertilizer, but we are not weaning ourselves from it.
Perhaps a good moment to begin weaning ourselves off the use of vast quantities of chemical fertilisers , start rebuilding our shattered soil and so on?
Where do people get this utopian idea that if we just use the right practices we can get away from nutrient inputs?
Crop rotation is beneficial but does not return nutrients to the soil.
If you are harvesting crops, it's not ♻️, it's
⬆️⬆️⬆️⬆️⬆️⬆️⬆️⬆️
EVEN with legumes.
Crop rotation, even diverse crop rotation, is not an "organic practice," IT IS A FARMING PRACTICE, used by farmers centuries before anyone knew what "organic farming" was.
This is just more marketing nonsense.
This abstract explores how the organic practice of using diverse rotations to reduce pest and disease and weed levels in following crops can be applied on non-organic farms:
@SoilAssociation
Tillage, which destroys soil structure, is considered "ecological weed management" but herbicide use, which maintains soil structure, is not.
Why? "Ecological" has come to mean "organic" for many, without consideration of end effects.
A double inconvenient truth for many: neither nitrogen fertilizer nor glyphosate destroys soil.
And, while there are always tradeoffs, these tools can even be beneficial; N fertilizer for building organic matter and glyphosate for helping reduce tillage to reduce erosion.
Does synthetic nitrogen fertilizer burn up soil organic matter?
Multiple studies say NO.
N fertilizer actually slows loss of old soil organic matter and increases microbial biomass and new soil organic matter.
New from
@jwadeexperience
and I:
The sales pitch:
"1 trillion microbes per kg"
"works like magic"
Do the math:
At the recommended application rate, this increases the microbes (bacteria only in calculations) in top 3" of soil by a whopping 0.0003%.
Stay skeptical.
Science is not about what we want, but how things actually are. With cover crop mixtures, the cumulative research results from 27 studies show that, at best, finding a mixture that will beat the best monoculture is quite difficult.
Regenerative agriculture would better without the organic-tending stance on synthetic fertilizers and pesticides, without pop-ecology, and without the "save the planet" motive.
Just no-till crops and cover crops in a decent rotation with grazed perennials to "stop erosion."
Want to improve your soil microbiology? Minimize your tillage.
In actual farmed fields, across a region and soil types, reducing tillage had a larger effect than even crop rotation diversity.
Tillage, texture, or crop diversity – which factor most influences soil microbial abundance and diversity? A recent
#SSSAJ
on-farm study conducted by Agyei et al. revealed that tillage significantly affects the soil's microbial community
The more you know about soil microbes, without having expertise on the topic, the more likely you are to try to micromanage them with dubious products or practices.
Better to improve the soil physical environment, protect your improvements, and let microbes do their thing.
?
What is the effect of glyphosate on soils in corn and soybean production?
Just published: "No effects of glyphosate were found on soil microbial communities associated with glyphosate-resistant corn and soybean varieties across diverse farming systems."
From crop biomass to soil organic matter (SOM), this paper conservatively estimates that ~90% of mass is lost.
From other estimates, composting of plant biomass (not manure) has about the same ~90% loss.
Building SOM is difficult.
Open access.
Agroecology: Just diversify!
Research comparing diversified to simplified cropping systems: 50.9% of trials show reduced yield, 42.8% show reduced biodiveristy.
Farmers: monoculture crops in rotation. 👍
Regarding glyphosate effects on the soil, it is important to note that there are always effects when we do or add something to the soil. What the evidence shows is that glyphosate does not drastically disrupt the soil ecosystem. Any minor changes should be evaluated in comparison
More research on glyphosate impacts on soil microbiology: neither soil bacteria and fungal diversity (alpha and beta) nor functional potential were impacted by cumulative glyphosate doses.
If you want to sequester carbon, put it deep in the soil, but if you want to improve your soil's function, concentrate soil organic matter near the surface.
This concentration of SOM at the surface can be used as a simple soil health measurement.
Crop yield was not affected by soil Ca:Mg ratio for any crop in any year...over the 6 years of the study, corn yields were positively related to increases in soil pH ... managing soil acidity remains a fundamental tool to improve crop yields." Open access
Biological seed treatments for soybeans, 50 locations over 2 years: Nothing worked everywhere in every year. When they did work, yield increases were small.
More details to come.
Do biological seed treatments work? Collaborative
@SoybeanScience1
#SoyResearch
compared common options, with state soy checkoffs and
@UnitedSoy
support. Initial results show any benefits are local and conditional, with in-depth analysis coming.
Some call this "nature-friendly farming" but it was NOT the farming practices that boosted birds and butterflies - they remained the same - it was land taken out of production to create habitat.
Habitat made the difference, not farming practices. (land sparing/restoration)
NEWS: Agri-environment measures boosted local bird and butterfly populations on a large-scale commercial farm, a decade-long study led by
@UK_CEH
has found
Ha! "replenishing the soil with nutrients" The things people say, and probably believe, to support organic farming.
I have never seen that said of using herbicides to do the exact same thing.
Extraordinary claim explained by ordinary practice?
Gabe Brown claimed to have increased soil organic matter from 6.1% to 11.1% in just 3 years. I challenged that, based on his listed practices.
We may now have an explanation: bale grazing.
"With widespread nitrogen limitation, organisms that can fix N would seem to have an advantage. Why don’t they proliferate & eliminate the N deficit? Why can’t we let biological N fixation fix our N fertilizer problem?"
My latest...
Public Service Announcement: Biofertilizers ARE NOT fertilizers. They are inoculants that might fix nitrogen or help make other nutrients more available. Unlike real fertilizers, in themselves they do not add nutrients to your soil.
It is unfortunate that science uses this
The 4 pillars of modern civilization:
1. Ammonia (nitrogen fertilizer)
2. Plastics
3. Steel
4. Cement
Why?
Indispensable for function,
Needed in large quantities,
Not readily replaceable with other materials.
The quote below shows a basic misunderstanding of agriculture.
If nature's "highly effective system" were up to feeding us all, we wouldn't need agriculture.
The fact is, we do agriculture precisely because nature CANNOT feed us.
From GMOs to regenerative agriculture: a scientist’s journey | Dr. Laura Kavanaugh went from developing GM crops at Syngenta to advancing regenerative agriculture
@AdvancingEcoAg
Effective Microorganisms® (EM) found ineffective: "EM did not produce a discernible effect on soil biological or chemical properties, nor did it influence the decomposition process of the cover crop."
Not a field study, open access.
This is what you get when you send a meteorologist to cover agriculture.
Organic marketing slogans.
Simplistic explanations,
Misinformation.
Unfortunately, it's also what you get when you send most journalists to cover agriculture.
CNN meteorologist Derek Van Dam flies to Southern California to learn more about regenerative agriculture and why the future of farming might come from the past.
2/6 Rather, the observed links are correlations; biodiversity is not the cause.
Instead, the analysis suggests that species COMPOSITION drives ecosystem functioning. YES. !
As in legume+non-legume cover crops.
Here is the paper, not open access.
Compost can provide remarkable soil health benefits, but when the soil that generated the biomass for the compost is considered, many rates of compost application are neither sustainable nor scalable; they resemble a pyramid scheme.
My newest...
A good summary by a cancer epidemiologist.
"Glyphosate is a boon to agriculture and humanity. Let’s refocus the energy and resources spent on trying to demonize this useful and valuable chemical on problems that really matter."
Cover crops help reduce soil erosion, no question there! Ever wondered why
#CoverCropsWork
? Check out this article:
OR check out our website! We can tell you why they work and what species to use for your soil health goals!
Think you have a soil biology problem? Think again...it's more likely you have a soil habitat problem.
And don't fall for alternative methods...a few proven practices will often do.
Don't overthink your soil biology. My latest...
Can ag stop focusing on yield?
Not yet, concludes this WRI report. Even with reduced food waste, diet changes, and less biofuel production, we still need productivity increases to avoid cropland expansion.
We definitely can't allow yields to decrease.
This is worthy of repeating: "There is no ‘ideal’ soil microbial community."
"We should not expect healthy soils to have a single ‘optimal’ community type - or that more microbial diversity is always better."
Needed repost:
What are the effects of glyphosate on soils in corn and soybean production? "No effects of glyphosate were found on soil microbial communities associated with glyphosate-resistant corn and soybean varieties across diverse farming systems."
True story: managed grazing can provide benefits
Based on true story: cattle are needed in all ag operations
Inspired by true story: grazing cattle can save us from climate change and there's no such thing as eating too much meat
Research finds water use by cover crops in dryland cropping often reduces yield of the following crop. Details of the climate matter here, but these are not solutions:
❌higher infiltration rates
❌cover crop mixtures
❌plants increasing rain
My latest .
Science: an attempt at neutral disinterest in the results with the goal of finding the truth.
Activist science: a motivated effort to prove something is so.
Nitpicking? Not really. It's a problem with any issue that people are passionate about: soil health, biodiversity...
Here are my essentials of sustaining agricultural production:
1. Protect the soil
2. Maintain soil fertility
3. Use water efficiently
4. Protect the crop
In order of importance and therefore, attention.
Why do so many people think we must learn from nature, mimic nature, or use nature as a standard for agriculture, when there is little evidence of any mechanism that would optimize natural ecosystems for producing food?
NMSU researchers assessed microbial community responses after cover crop termination. Responses varied w/ cover crops at & after 36 d post-termination, while effects did not persist for a year, highlighting the value of continuous living roots
@nmsu_aces
At local industrial hemp meeting, a speaker estimated that CBD demand could be met with just 20,000 acres in the US and that 500,000 were grown last season.
Show me a cropped field and I'll show you a native ecosystem that has been destroyed. It's how food is produced.
To best protect nature:
1. Intensively produce crops on existing farmland,
2. Minimize off-farm effects, and
3. Rewild marginal farmland.
How to greenwash a crop: "in its cultivation and production the crop has a little to no impact on water, land, forest, air or soil." It's the pet rock of crops.
Unless it is being foraged in a forest, this cannot be true.
Journalists, do better.
Why farmers would rather listen to regenerative ag speakers (1) than those from Extension/University (2):
1 Fertilizer suppresses mycorrhizal fungi
2 It depends
1 Mycorrhizal fungi are key to soil health
2 In some systems
1 Fert. suppresses root exudates
2 More research needed
No difference in soil bacterial diversity between 4-yr organic and no-till with herbicides.
Also, I oppose the use of "chemical no-till" and "chemically- managed" as shorthand for use of pesticides and fertilizers. It is misleading and academic journals should aim higher.
New in Geoderma,
#openaccess
: "Soil bacterial communities of wheat vary across the growing season and among dryland farming systems" by Suzanne Ishaq, Tim Seipel, Carl Yeoman, and Fabian Menalled.
@montanastate
An interesting discussion of the various theories of why organic matter persists in soils. Open access.
This figure does not show any of the theories fading away; they are all persistent. Are they all true in some sense or context?
The reality of farming is not as simple as often portrayed in social media. While the general public can be enticed to believe simplistic versions of agriculture, or pop-ecology, the truth is more complex, nearly always involving difficult tradeoffs.
Despite this being repeated over and over until most people probably believe it, there is little evidence that soil health (apart from its nutrient status) results in healthier or more nutritious food.
Healthy soils mean healthy, safe & nutritious food.
In fact, soil health & fertility have a direct influence on the nutrient content of food crops 🌱
Let's take
#SoilAction
!
At first glance, this seems promising, but I always ask, what is cost @ effective rate?
Inoculant applied at ~6691 lb/ac.
Bulk commercial mycorrhizal inoculant for $15/lb.
So this would cost a farmer $100,000/acre.
Successful microbiome engineering is very expensive.
Successful microbiome engineering in agricultural fields. Our new paper in
@NatureMicrobiol
demonstrates that large-scale inoculation with arbuscular mycorrhizal fungi works and can promote crop yield up to 40%.
@SteffiLutz
;
@NBodenhausen
;
@KSchlaeppi
This headline is a blatant lie.
The paper being reported is a hazard analysis, not a risk analysis:
>60% of total results were from labs, NOT the field
and there was NO evaluation of actual secondary effects soil health.
With regenerative agriculture, it's important to distinguish the results of livestock-only systems from those of annual cropping systems. What is possible with grazing is not possible with annual crops. They function differently.
Long term no-till with cover crops: "The combination of CC with NT practices enhanced soil oxygen availability and resilience to extreme precipitation events."
Water drains better.
Open access.
Article alert!📢
Forty-two years of no-tillage and cover cropping improved soil oxygen availability and resilience
Research letter by Lussich & colleagues
#OpenAccess
@UT_Herbert
@UTAgResearch
@UTIAg
No, compost is not the secret.
Compost is just importing biomass from a large area and applying it to a smaller area. Of course it works, but it does not scale and ignores the effects on the land that originally produced it.
The number of people who have romantic ideals of how agriculture should look and work AND who also get most of their food from farms that look and work like they envision, is tiny.
There is no reason to think that judicious use of synthetic fertilizers and pesticides cannot be a part of any regenerative agriculture.
Chemophobia is not a requirement.
Healthy soils produce healthy crops, right? Nope.
Although it would seem the very definition of soil health, this popular thinking is off. Soil health can help with soilborne diseases, but it is not disease suppression. My latest here...
Turns out it isn't the "factory" part of "factory farming" that environmentalists oppose, at least for plants; pvc piping, artificial lighting, heating, cooling, water pumps and ventilation, and lots of stainless steel. Maybe they just don't like farms?
Did you know farmers can grow plants indoors without soil? Soilless farming aims to reduce many of the more harmful effects of conventional field farming, including decreasing pressures on land, biodiversity, natural habitat, and climate:
"A meta-analysis of 1,521 field observations of advanced nitrogen-management practices published during the past two decades...finds 11 key practices that enhance crop yield and fertilizer NUE while decreasing nitrogen losses to the environment."
New biochar study:
High-value crop and high application rates (2 tons/ac concentrated below crop row, effective rate=20 tons/ac), 3 types of biochar over 3 years...
No effect on yields, minimal effects on soil health.
Biochar; the most researched, least used soil amendment.
Another study on soil microbial diversity.
Fungal and bacterial diversity linked to 3 factors: climate, pH and land cover. pH is the only one you can manage.
So,
1. Don't worry about your soil's microbial diversity.
2. If you want to manage it, don't let your pH get too low.
Cautionary tale of believing regenerative agriculture's hype about soil biology providing nutrients.
“In time, though, those farms are going to mine those soils. It just might take a little bit longer than it did for us.”
HT
@ursellberger
Every time I check out the source of a popular but misleading tweet about soil/crops/agriculture (you can filter searches by # of retweets in tweetdeck), the sender almost always has 10K followers, sometimes many more.
Enticing but untrue stories are more popular than reality.
Confirmed:
1. Crop rotation is still beneficial.
2. Legumes still beneficial in low fertility systems.
3. Benefits increase over time (probably because of a buildup of soilborne pathogens in monocropping)
Open access.
"research found that within one month of tillage events, in the surface 10 cm of the soil there were losses of 52% of microbial biomass and 33% of organic carbon."
Most people in ag would have guessed this result, but it's good to have actual evidence.