Andrew McGuire
@agronomistag.bsky.social
Views of an agronomist on soil, farming, and science. Evidence-based agriculture. Washington State University Extension. https://t.co/RZ11P3ozYm
Same @ on X.
Same @ on X.
It's sustainable ag with a different vibe.
November 3, 2025 at 5:16 PM
It's sustainable ag with a different vibe.
Bluesky VS X.
Agriculture is not on Bluesky.
Agriculture is not on Bluesky.
October 30, 2025 at 4:15 PM
Bluesky VS X.
Agriculture is not on Bluesky.
Agriculture is not on Bluesky.
Cover crop mixture research, 5 states, 17 site-years, concludes that CC mixture diversity and seeding rate did not consistently improve CC performance, measured soil parameters, or cash crop yields.
But they cost more.
Open access.
www.tandfonline.com/doi/full/10...
But they cost more.
Open access.
www.tandfonline.com/doi/full/10...
September 25, 2025 at 6:02 PM
Cover crop mixture research, 5 states, 17 site-years, concludes that CC mixture diversity and seeding rate did not consistently improve CC performance, measured soil parameters, or cash crop yields.
But they cost more.
Open access.
www.tandfonline.com/doi/full/10...
But they cost more.
Open access.
www.tandfonline.com/doi/full/10...
Dramatically? 🤔 Fertilizers yes, fungi not so much.
SPUN spin.
SPUN spin.
September 22, 2025 at 4:15 PM
Dramatically? 🤔 Fertilizers yes, fungi not so much.
SPUN spin.
SPUN spin.
The report that concludes "herbicides devastate soil life" gives little to support that conclusion. Yes, glyphosate has some effects on earthworms, but compared to tillage, minimal. 2,4-D, one study on collembola. Acetochlor, one study on nematodes.
This is not devastation.
This is not devastation.
May 9, 2025 at 3:42 PM
The report that concludes "herbicides devastate soil life" gives little to support that conclusion. Yes, glyphosate has some effects on earthworms, but compared to tillage, minimal. 2,4-D, one study on collembola. Acetochlor, one study on nematodes.
This is not devastation.
This is not devastation.
Solar panels reduce grassland production. From 17 solar parks across the Netherlands.
Open access.
Gap=between panels, Below=under panels
nph.onlinelibrary.wiley.com/doi/full/10....
Open access.
Gap=between panels, Below=under panels
nph.onlinelibrary.wiley.com/doi/full/10....
May 7, 2025 at 8:57 PM
Solar panels reduce grassland production. From 17 solar parks across the Netherlands.
Open access.
Gap=between panels, Below=under panels
nph.onlinelibrary.wiley.com/doi/full/10....
Open access.
Gap=between panels, Below=under panels
nph.onlinelibrary.wiley.com/doi/full/10....
My assumptions/calculations.
April 24, 2025 at 7:29 PM
My assumptions/calculations.
Ag discussions on Bluesky vs X below. Telling.
April 20, 2025 at 9:41 PM
Ag discussions on Bluesky vs X below. Telling.
How do you tell if a new soil biology discovery is useful or just interesting? Ask some questions before chasing the latest buzzword.
April 16, 2025 at 3:35 PM
How do you tell if a new soil biology discovery is useful or just interesting? Ask some questions before chasing the latest buzzword.
Here is how Brassicas are being used for "biofumigation" in potato production here in the Columbia Basin of Washington state.
Using Green Manures in Potato Cropping Systems
pubs.extension.wsu.edu/using-green...
Using Green Manures in Potato Cropping Systems
pubs.extension.wsu.edu/using-green...
April 4, 2025 at 3:51 PM
Here is how Brassicas are being used for "biofumigation" in potato production here in the Columbia Basin of Washington state.
Using Green Manures in Potato Cropping Systems
pubs.extension.wsu.edu/using-green...
Using Green Manures in Potato Cropping Systems
pubs.extension.wsu.edu/using-green...
"Natural" doesn't mean safe. Both the soil fumigant Metam Sodium and some Brassica plants produce methyl isothiocyanate. It's the dose that makes the difference between spicy mustard and a potent pesticide.
April 4, 2025 at 3:51 PM
"Natural" doesn't mean safe. Both the soil fumigant Metam Sodium and some Brassica plants produce methyl isothiocyanate. It's the dose that makes the difference between spicy mustard and a potent pesticide.
Where is regenerative agriculture in the movement hype cycle?
I think it is somewhere past the peak of inflated expectations, with some holdouts.
Graphic from www.sciencedirect.com/science/arti...
I think it is somewhere past the peak of inflated expectations, with some holdouts.
Graphic from www.sciencedirect.com/science/arti...
March 26, 2025 at 3:08 PM
Where is regenerative agriculture in the movement hype cycle?
I think it is somewhere past the peak of inflated expectations, with some holdouts.
Graphic from www.sciencedirect.com/science/arti...
I think it is somewhere past the peak of inflated expectations, with some holdouts.
Graphic from www.sciencedirect.com/science/arti...
Meta-analysis of commercial mycorrhizal inoculant research results:
Failure is the norm.
Open access. nph.onlinelibrary.wiley.com/doi/full/10....
Failure is the norm.
Open access. nph.onlinelibrary.wiley.com/doi/full/10....
March 19, 2025 at 5:30 PM
Meta-analysis of commercial mycorrhizal inoculant research results:
Failure is the norm.
Open access. nph.onlinelibrary.wiley.com/doi/full/10....
Failure is the norm.
Open access. nph.onlinelibrary.wiley.com/doi/full/10....
No doubt there's a rational economic reason for the change in food trade, and it isn't because we are suddenly farming less land. We'd probably grow a lot more fruit here if people would eat more.
March 12, 2025 at 4:05 PM
No doubt there's a rational economic reason for the change in food trade, and it isn't because we are suddenly farming less land. We'd probably grow a lot more fruit here if people would eat more.
Moving towards looking at processes driving soil health rather than practices. Here, biomass production, which indicates the energy flow through a system.
Δ Biomass correlated well with Δ Soil Health.
www.sciencedirect.com/science/art...
Δ Biomass correlated well with Δ Soil Health.
www.sciencedirect.com/science/art...
March 12, 2025 at 12:21 PM
Moving towards looking at processes driving soil health rather than practices. Here, biomass production, which indicates the energy flow through a system.
Δ Biomass correlated well with Δ Soil Health.
www.sciencedirect.com/science/art...
Δ Biomass correlated well with Δ Soil Health.
www.sciencedirect.com/science/art...
Disking and incorporation of the mustard in October, usually before potatoes the next spring.
March 6, 2025 at 7:06 PM
Disking and incorporation of the mustard in October, usually before potatoes the next spring.
If biomass is crucial for benefits, should we fertilize cover crops?
Example in my article (linked below) is a fully fertilized mustard green manure crop. Between mid-August and late October, it produces >8000 lb/ac (8.9Mg/ha) for soilborne disease suppression and soil health.
Example in my article (linked below) is a fully fertilized mustard green manure crop. Between mid-August and late October, it produces >8000 lb/ac (8.9Mg/ha) for soilborne disease suppression and soil health.
March 6, 2025 at 7:06 PM
If biomass is crucial for benefits, should we fertilize cover crops?
Example in my article (linked below) is a fully fertilized mustard green manure crop. Between mid-August and late October, it produces >8000 lb/ac (8.9Mg/ha) for soilborne disease suppression and soil health.
Example in my article (linked below) is a fully fertilized mustard green manure crop. Between mid-August and late October, it produces >8000 lb/ac (8.9Mg/ha) for soilborne disease suppression and soil health.
Do memes count?
February 26, 2025 at 12:34 AM
Do memes count?
Contrary to popular belief, cover crop benefits from the best monocultures are often similar to the best mixtures while also being less expensive, easier to manage, and easier to figure out the best species.
csanr.wsu.edu/contrary-sc...
csanr.wsu.edu/contrary-sc...
February 24, 2025 at 7:01 PM
Contrary to popular belief, cover crop benefits from the best monocultures are often similar to the best mixtures while also being less expensive, easier to manage, and easier to figure out the best species.
csanr.wsu.edu/contrary-sc...
csanr.wsu.edu/contrary-sc...
Too many people focus on eating nutrient-dense foods while consuming low truth-density information. This ultra-processed info-junk is often crafted by hucksters to appeal to you, not for its factual content.
One method of combatting this:
One method of combatting this:
February 18, 2025 at 5:05 PM
Too many people focus on eating nutrient-dense foods while consuming low truth-density information. This ultra-processed info-junk is often crafted by hucksters to appeal to you, not for its factual content.
One method of combatting this:
One method of combatting this:
It's sustainable ag with an attitude.
February 15, 2025 at 4:12 PM
It's sustainable ag with an attitude.
Does regenerative agriculture bring any new practices?
There are the soil health principles, and its goal of restoring soils, and lots of other ideas, but the practices remain the same.
There are the soil health principles, and its goal of restoring soils, and lots of other ideas, but the practices remain the same.
February 7, 2025 at 2:42 AM
Does regenerative agriculture bring any new practices?
There are the soil health principles, and its goal of restoring soils, and lots of other ideas, but the practices remain the same.
There are the soil health principles, and its goal of restoring soils, and lots of other ideas, but the practices remain the same.
They don't add much value other than perhaps a preserve for beneficial insects. The circles have to fit in the square layout of roads. In regions where these roads were not a barrier, I think they do more what you are thinking. Here's an area to the south of us where this is done.
February 3, 2025 at 4:24 PM
They don't add much value other than perhaps a preserve for beneficial insects. The circles have to fit in the square layout of roads. In regions where these roads were not a barrier, I think they do more what you are thinking. Here's an area to the south of us where this is done.
Something I've wondered; do oilseed radish's big roots compact surface soil? The roots displace a lot of soil so the only way they wouldn't compact it is if the soil moved upward. Some evidence for compaction below.
Or is it just lack of surface roots?
nature.berkeley.edu/classes/es1...
Or is it just lack of surface roots?
nature.berkeley.edu/classes/es1...
January 31, 2025 at 11:30 PM
Something I've wondered; do oilseed radish's big roots compact surface soil? The roots displace a lot of soil so the only way they wouldn't compact it is if the soil moved upward. Some evidence for compaction below.
Or is it just lack of surface roots?
nature.berkeley.edu/classes/es1...
Or is it just lack of surface roots?
nature.berkeley.edu/classes/es1...
