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You seem very certain that fertilizer is required. Given what we know of agriculture today, that seems reasonable. But something, somehow grew 4-8ft of deep to

You seem very certain that fertilizer is required. Given what we know of agriculture today, that seems reasonable. But something, somehow grew 4-8ft of deep topsoil on the prairies in the US that are now prime farmland. Haber Bosch wasn't around 300 or 3000 years ago, nor were people tilling and planting. How did these plants get enough nitrogen to thrive? How do current grass fed beef ranchers grow enough grass to grow cattle today? Surely they aren't fertilizing the grass. Some folks say that there are free living nitrogen fixing bacteria that can live in the soil, provided that they're getting sugars from growing plants. It seems reasonable.

troupo 3y ago
> Haber Bosch wasn't around 300 or 3000 years ago, nor were people tilling and planting. How did these plants get enough nitrogen to thrive? Are you claiming that 9 billion people lived 300 or 3000 years ago and planted and regularly harvested high yield crops to feed themselves? > How do current grass fed beef ranchers grow enough grass to grow cattle today? Surely they aren't fertilizing the grass. Yes, yes they are.
- johndhi 3y ago
  I live in an old cattle ranch and the fertilizer use over the years made my well really high in nitrates
- westurner 3y ago
  Food security has probably been an issue since forever. History of Agriculture: https://en.wikipedia.org/wiki/History_of_agriculture https://en.wikipedia.org/wiki/History_of_agriculture : > The development of agriculture about 12,000 years ago changed the way humans lived. They switched from nomadic hunter-gatherer lifestyles to permanent settlements and farming. [1] World population: https://en.wikipedia.org/wiki/World_population https://en.wikipedia.org/wiki/World_population : > It took over 200,000 years of human prehistory and history for the human population to reach one billion and only 219 years more to reach 8 billion. [3] Food security: https://en.wikipedia.org/wiki/Food_security https://en.wikipedia.org/wiki/Food_security Soil fertility > Soil depletion: https://en.wikipedia.org/wiki/Soil_fertility https://en.wikipedia.org/wiki/Soil_fertility : > Topsoil depletion occurs when the nutrient-rich organic topsoil, which takes hundreds to thousands of years to build up under natural conditions, is eroded or depleted of its original organic material.[13] Historically, many past civilizations' collapses can be attributed to the depletion of the topsoil. Since the beginning of agricultural production in the Great Plains of North America in the 1880s, about one-half of its topsoil has disappeared. [14] > Depletion may occur through a variety of other effects, including overtillage (which damages soil structure), underuse of nutrient inputs which leads to mining of the soil nutrient bank, and salinization of soil. Soil management : https://en.wikipedia.org/wiki/Soil_management https://en.wikipedia.org/wiki/Soil_management : > Soils can sequester carbon dioxide (CO2) from the atmosphere, primarily by storing carbon as soil organic carbon (SOC) through the process of photosynthesis. CO2 can also be stored as inorganic carbon but this is less common. Converting natural land to agricultural land releases carbon back into the atmosphere. The amount of carbon a soil can sequester depends on the climate and current and historical land-use and management.[6] Cropland has the potential to sequester 0.5–1.2 Pg C/year and grazing and pasture land could sequester 0.3–0.7 Pg C/year.[7] Agricultural practices that sequester carbon can help mitigate climate change.[8] Intensive farming deteriorates the functionality of soils. > Methods that significantly enhance carbon sequestration in soil include no-till farming, residue mulching, cover cropping, and crop rotation, all of which are more widely used in organic farming than in conventional farming.[9][10] Because only 5% of US farmland currently uses no-till and residue mulching, there is a large potential for carbon sequestration FWIU new methods of onsite green ammonia production for fertilizer could help solve food security, but the nitrogen runoff is causing algal blooms in waterways. A (soap-like) surfactant like JADAM Wetting Agent (JWA) which causes the applied treatments to stick to the plants might reduce fertilizer runoff levels; but Nitrogen-based fertilizer alone does not regenerate all of the components of topsoil. https://www.google.com/search?q=jadam+jwa https://www.google.com/search?q=jadam+jwa Mycorrhizae fungus in the soil help get nutrients to plant roots, and they need to be damp in order to prevent soil from turning to dirt due to solar radiation and oxidation. https://youtube.com/@soilfoodwebschool https://youtube.com/@soilfoodwebschool Urea breaks down into Nitrogen and CO2 in the soil. Maybe that used to scale (before we had 8b people on here). TIL that rainwater is higher in nitrogen from falling though air (which contains H2O, CO2, N, O2, CO). Irrigation > Challenges https://en.wikipedia.org/wiki/Irrigation https://en.wikipedia.org/wiki/Irrigation : > However, if the soil is under irrigated, it gives poor soil salinity control which leads to increased soil salinity with the consequent buildup of toxic salts on the soil surface in areas with high evaporation. This requires either leaching to remove these salts and a method of drainage to carry the salts away. Irrigation with saline or high-sodium water may damage soil structure owing to the formation of alkaline soil. From "Idiocracy": > "For the last time, I'm pretty sure what's killing the crops is this Brawndo stuff. >> But Brawndo's got what plants crave. It's got electrolytes. [Sodium (NaCl), Potassium (K), Water (H2O)) TIL that basic soil and plant health and farming things are new material for me, an otherwise qualified eater.
  - myshpa 3y ago
    Agree, very interesting stuff. Before I get to the soils, animal ag intro. https://www.colorado.edu/ecenter/2022/03/15/it-may-be-uncomfortable-we-need-talk-about-it-animal-agriculture-industry-and-zero-waste https://www.colorado.edu/ecenter/2022/03/15/it-may-be-uncomf... The animal agriculture industry is the leading cause of most environmental degradation that is currently occurring. These detrimental effects happen due to overgrazing, habitat loss, overfishing, and more. We are currently in the next mass extinction and animal agriculture is only fueling this catastrophe. Waste in the meat industry, too, is a major problem in of itself. https://www.pnas.org/doi/10.1073/pnas.142033699 https://www.pnas.org/doi/10.1073/pnas.142033699 Tracking the ecological overshoot of the human economy Our accounts indicate that human demand may well have exceeded the biosphere's regenerative capacity since the 1980s. According to this preliminary and exploratory assessment, humanity's load corresponded to 70% of the capacity of the global biosphere in 1961, and grew to 120% in 1999. https://www.nature.com/articles/s41893-020-00603-4 https://www.nature.com/articles/s41893-020-00603-4 The carbon opportunity cost of animal-sourced food production on land ... shifts in global food production to plant-based diets by 2050 could lead to sequestration of 332–547 GtCO2, equivalent to 99–163% of the CO2 emissions budget consistent with a 66% chance of limiting warming to 1.5 °C And back to soils ... https://www.smithsonianmag.com/science-nature/soil-has-microbiome-too-180960088/ https://www.smithsonianmag.com/science-nature/soil-has-micro... Soil Has a Microbiome, Too - The unique mix of microbes in soil has a profound effect on which plants thrive and which ones die https://www.theguardian.com/environment/2022/may/07/secret-world-beneath-our-feet-mind-blowing-key-to-planets-future https://www.theguardian.com/environment/2022/may/07/secret-w... The secret world beneath our feet is mind-blowing – and the key to our planet’s future - Don’t dismiss soil: its unknowable wonders could ensure the survival of our species https://news.harvard.edu/gazette/story/2023/05/how-climate-change-may-threaten-soils-ability-to-capture-carbon/ https://news.harvard.edu/gazette/story/2023/05/how-climate-c... Getting to root of possible carbon storage changes due to climate change https://regenerationinternational.org/2023/02/16/maximizing-photosynthesis-and-root-exudates-through-regenerative-agriculture-to-increase-soil-organic-carbon-to-mitigate-climate-change/ https://regenerationinternational.org/2023/02/16/maximizing-... Maximizing Photosynthesis and Root Exudates through Regenerative Agriculture to Increase Soil Organic Carbon to Mitigate Climate Change https://www.theguardian.com/environment/2023/jul/04/improving-farming-soil-carbon-store-global-heating-target https://www.theguardian.com/environment/2023/jul/04/improvin... Improving soil could keep world within 1.5C heating target, research suggests Better farming techniques across the world could lead to storage of 31 gigatonnes of carbon dioxide a year, data shows
cyberax 3y ago
> Haber Bosch wasn't around 300 or 3000 years ago, nor were people tilling and planting. How did these plants get enough nitrogen to thrive? They didn't "thrive" in the modern sense. For example, a good yield in 1900 was around 16 bushels of wheat per acre, with the national average of 12 bushels. You could use somewhat better crop rotation techniques, waste a lot of effort on manual pest removal, and get to maybe 20-25 bushels. The current _average_ yield is 50 bushels per acre. And the top yields are around 100 bushels per acre ( https://www.statista.com/statistics/190370/top-10-us-states-for-wheat-yield-per-harvested-acre/ https://www.statista.com/statistics/190370/top-10-us-states-... ). Sorry for arcane units, they are traditional when talking about wheat. > How do current grass fed beef ranchers grow enough grass to grow cattle today? Surely they aren't fertilizing the grass. Yes, they do. Alfalfa doesn't require a lot of it (it's a nitrogen fixer itself), but other types of grass do. Corn for corn-fed beef certainly needs fertilizer. And corn-fed beef is around 96% of all beef in the US.
- myshpa 3y ago
  https://ourworldindata.org/land-use-diets https://ourworldindata.org/land-use-diets If the world adopted a plant-based diet we would reduce global agricultural land use from 4 to 1 billion hectares https://www.naturalnews.com/2022-12-09-organic-farming-produces-higher-yields-during-drought.html https://www.naturalnews.com/2022-12-09-organic-farming-produ... Report: Organic farming yields 40% more crops than conventional farming during drought https://www.scientificamerican.com/article/organic-farming-yields-and-feeding-the-world-under-climate-change/ https://www.scientificamerican.com/article/organic-farming-y... A new meta-analysis suggests farmers should take a hybrid approach to producing enough food for humans while preserving the environment https://www.downtoearth.org.in/news/agriculture/farmyard-manure-in-natural-farming-leads-to-higher-yield-than-conventional-method-study-89882 https://www.downtoearth.org.in/news/agriculture/farmyard-man... Farmyard manure in natural farming leads to higher yield than conventional method: Study https://www.nature.com/articles/nature11069 https://www.nature.com/articles/nature11069 with good management practices, particular crop types and growing conditions—organic systems can thus nearly match conventional yields, whereas under others it at present cannot https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0161673 https://journals.plos.org/plosone/article?id=10.1371/journal... Commercial Crop Yields Reveal Strengths and Weaknesses for Organic Agriculture in the United States The analysis we present here offers a new perspective, based on organic yield data collected from over 10,000 organic farmers representing nearly 800,000 hectares of organic farmland. Averaged across all crops, organic yield averaged 80% of conventional yield. However, several crops had no significant difference in yields between organic and conventional production, and organic yields surpassed conventional yields for some hay crops.
jillesvangurp 3y ago
Nutrients are of course required and depleted if you keep harvesting and removing them from the ecosystem. So you need a way to deliver some of that back. There are many ways to deliver nutrients and industrially produced fertilizers are merely one of those. A lot of organic farmers instead use things like compost, crop rotation, and no-till. No till keeps the soil healthy (by not disturbing it) and minimizes nutrient losses through erosion. Compost in the form of carbon rich wood chips or dead leaves, or nitrogen rich greens, or animal waste can do the rest. Certain cover crops actually add nitrogen to the soil. They take nitrogen from the air and deposit it in their roots. When the plants are harvested, the roots remain.
- cyberax 3y ago
  Gah. Quite a few of nutrients are _dependent_ in nature on erosion. Phosphorus is one of them, it's normally locked in very insoluble phosphates, that get broken down by weathering (erosion). No-till farming preserves nitrogen, which is the main limiting factor in agriculture. It also allows soil to have better water retention. The BIG downside is that no-till farming doesn't disrupt pests, so they can easily crowd out crops. > Certain cover crops actually add nitrogen to the soil. They take nitrogen from the air and deposit it in their roots Yes. That's why people had to leave fields fallow, to allow nitrogen fixing plants (such as clover) to grow and then compost in-place. The problem with that is an extremely poor efficiency of biological nitrogen fixation. It's a wonder that it works at all, honestly.
  - myshpa 3y ago
    > That's why people had to leave fields fallow, to allow nitrogen fixing plants (such as clover) to grow and then compost in-place Leaving fields fallow does allow the land to recover and can reduce certain pests and diseases. However, the primary purpose of leaving fields fallow historically wasn't necessarily for nitrogen-fixing plants to grow. That said, some traditional farming systems deliberately planted nitrogen-fixing cover crops, like clover, in rotation with other crops to replenish soil nitrogen. And let's not forget about nitrogen fixing trees. > an extremely poor efficiency of biological nitrogen fixation Biological nitrogen fixation may not be as immediately effective or efficient as directly applying synthetic nitrogen fertilizers, but it's a natural process that has sustained ecosystems for millennia. To say it has "extremely poor efficiency" might be an overgeneralization. In sustainable agriculture, the efficiency of nitrogen-fixing plants isn't solely measured by the speed or volume of nitrogen delivery but also by the myriad of other benefits they provide, such as improving soil structure, suppressing weeds, and promoting beneficial soil microbes. > It's a wonder that it works at all Biological nitrogen fixation is a well-established and crucial ecological process.

troupo 3y ago

> Haber Bosch wasn't around 300 or 3000 years ago, nor were people tilling and planting. How did these plants get enough nitrogen to thrive? Are you claiming that 9 billion people lived 300 or 3000 years ago and planted and regularly harvested high yield crops to feed themselves? > How do current grass fed beef ranchers grow enough grass to grow cattle today? Surely they aren't fertilizing the grass. Yes, yes they are.

johndhi 3y ago
I live in an old cattle ranch and the fertilizer use over the years made my well really high in nitrates
westurner 3y ago
Food security has probably been an issue since forever. History of Agriculture: https://en.wikipedia.org/wiki/History_of_agriculture https://en.wikipedia.org/wiki/History_of_agriculture : > The development of agriculture about 12,000 years ago changed the way humans lived. They switched from nomadic hunter-gatherer lifestyles to permanent settlements and farming. [1] World population: https://en.wikipedia.org/wiki/World_population https://en.wikipedia.org/wiki/World_population : > It took over 200,000 years of human prehistory and history for the human population to reach one billion and only 219 years more to reach 8 billion. [3] Food security: https://en.wikipedia.org/wiki/Food_security https://en.wikipedia.org/wiki/Food_security Soil fertility > Soil depletion: https://en.wikipedia.org/wiki/Soil_fertility https://en.wikipedia.org/wiki/Soil_fertility : > Topsoil depletion occurs when the nutrient-rich organic topsoil, which takes hundreds to thousands of years to build up under natural conditions, is eroded or depleted of its original organic material.[13] Historically, many past civilizations' collapses can be attributed to the depletion of the topsoil. Since the beginning of agricultural production in the Great Plains of North America in the 1880s, about one-half of its topsoil has disappeared. [14] > Depletion may occur through a variety of other effects, including overtillage (which damages soil structure), underuse of nutrient inputs which leads to mining of the soil nutrient bank, and salinization of soil. Soil management : https://en.wikipedia.org/wiki/Soil_management https://en.wikipedia.org/wiki/Soil_management : > Soils can sequester carbon dioxide (CO2) from the atmosphere, primarily by storing carbon as soil organic carbon (SOC) through the process of photosynthesis. CO2 can also be stored as inorganic carbon but this is less common. Converting natural land to agricultural land releases carbon back into the atmosphere. The amount of carbon a soil can sequester depends on the climate and current and historical land-use and management.[6] Cropland has the potential to sequester 0.5–1.2 Pg C/year and grazing and pasture land could sequester 0.3–0.7 Pg C/year.[7] Agricultural practices that sequester carbon can help mitigate climate change.[8] Intensive farming deteriorates the functionality of soils. > Methods that significantly enhance carbon sequestration in soil include no-till farming, residue mulching, cover cropping, and crop rotation, all of which are more widely used in organic farming than in conventional farming.[9][10] Because only 5% of US farmland currently uses no-till and residue mulching, there is a large potential for carbon sequestration FWIU new methods of onsite green ammonia production for fertilizer could help solve food security, but the nitrogen runoff is causing algal blooms in waterways. A (soap-like) surfactant like JADAM Wetting Agent (JWA) which causes the applied treatments to stick to the plants might reduce fertilizer runoff levels; but Nitrogen-based fertilizer alone does not regenerate all of the components of topsoil. https://www.google.com/search?q=jadam+jwa https://www.google.com/search?q=jadam+jwa Mycorrhizae fungus in the soil help get nutrients to plant roots, and they need to be damp in order to prevent soil from turning to dirt due to solar radiation and oxidation. https://youtube.com/@soilfoodwebschool https://youtube.com/@soilfoodwebschool Urea breaks down into Nitrogen and CO2 in the soil. Maybe that used to scale (before we had 8b people on here). TIL that rainwater is higher in nitrogen from falling though air (which contains H2O, CO2, N, O2, CO). Irrigation > Challenges https://en.wikipedia.org/wiki/Irrigation https://en.wikipedia.org/wiki/Irrigation : > However, if the soil is under irrigated, it gives poor soil salinity control which leads to increased soil salinity with the consequent buildup of toxic salts on the soil surface in areas with high evaporation. This requires either leaching to remove these salts and a method of drainage to carry the salts away. Irrigation with saline or high-sodium water may damage soil structure owing to the formation of alkaline soil. From "Idiocracy": > "For the last time, I'm pretty sure what's killing the crops is this Brawndo stuff. >> But Brawndo's got what plants crave. It's got electrolytes. [Sodium (NaCl), Potassium (K), Water (H2O)) TIL that basic soil and plant health and farming things are new material for me, an otherwise qualified eater.
- myshpa 3y ago
  Agree, very interesting stuff. Before I get to the soils, animal ag intro. https://www.colorado.edu/ecenter/2022/03/15/it-may-be-uncomfortable-we-need-talk-about-it-animal-agriculture-industry-and-zero-waste https://www.colorado.edu/ecenter/2022/03/15/it-may-be-uncomf... The animal agriculture industry is the leading cause of most environmental degradation that is currently occurring. These detrimental effects happen due to overgrazing, habitat loss, overfishing, and more. We are currently in the next mass extinction and animal agriculture is only fueling this catastrophe. Waste in the meat industry, too, is a major problem in of itself. https://www.pnas.org/doi/10.1073/pnas.142033699 https://www.pnas.org/doi/10.1073/pnas.142033699 Tracking the ecological overshoot of the human economy Our accounts indicate that human demand may well have exceeded the biosphere's regenerative capacity since the 1980s. According to this preliminary and exploratory assessment, humanity's load corresponded to 70% of the capacity of the global biosphere in 1961, and grew to 120% in 1999. https://www.nature.com/articles/s41893-020-00603-4 https://www.nature.com/articles/s41893-020-00603-4 The carbon opportunity cost of animal-sourced food production on land ... shifts in global food production to plant-based diets by 2050 could lead to sequestration of 332–547 GtCO2, equivalent to 99–163% of the CO2 emissions budget consistent with a 66% chance of limiting warming to 1.5 °C And back to soils ... https://www.smithsonianmag.com/science-nature/soil-has-microbiome-too-180960088/ https://www.smithsonianmag.com/science-nature/soil-has-micro... Soil Has a Microbiome, Too - The unique mix of microbes in soil has a profound effect on which plants thrive and which ones die https://www.theguardian.com/environment/2022/may/07/secret-world-beneath-our-feet-mind-blowing-key-to-planets-future https://www.theguardian.com/environment/2022/may/07/secret-w... The secret world beneath our feet is mind-blowing – and the key to our planet’s future - Don’t dismiss soil: its unknowable wonders could ensure the survival of our species https://news.harvard.edu/gazette/story/2023/05/how-climate-change-may-threaten-soils-ability-to-capture-carbon/ https://news.harvard.edu/gazette/story/2023/05/how-climate-c... Getting to root of possible carbon storage changes due to climate change https://regenerationinternational.org/2023/02/16/maximizing-photosynthesis-and-root-exudates-through-regenerative-agriculture-to-increase-soil-organic-carbon-to-mitigate-climate-change/ https://regenerationinternational.org/2023/02/16/maximizing-... Maximizing Photosynthesis and Root Exudates through Regenerative Agriculture to Increase Soil Organic Carbon to Mitigate Climate Change https://www.theguardian.com/environment/2023/jul/04/improving-farming-soil-carbon-store-global-heating-target https://www.theguardian.com/environment/2023/jul/04/improvin... Improving soil could keep world within 1.5C heating target, research suggests Better farming techniques across the world could lead to storage of 31 gigatonnes of carbon dioxide a year, data shows

cyberax 3y ago

> Haber Bosch wasn't around 300 or 3000 years ago, nor were people tilling and planting. How did these plants get enough nitrogen to thrive? They didn't "thrive" in the modern sense. For example, a good yield in 1900 was around 16 bushels of wheat per acre, with the national average of 12 bushels. You could use somewhat better crop rotation techniques, waste a lot of effort on manual pest removal, and get to maybe 20-25 bushels. The current _average_ yield is 50 bushels per acre. And the top yields are around 100 bushels per acre ( https://www.statista.com/statistics/190370/top-10-us-states-for-wheat-yield-per-harvested-acre/ https://www.statista.com/statistics/190370/top-10-us-states-... ). Sorry for arcane units, they are traditional when talking about wheat. > How do current grass fed beef ranchers grow enough grass to grow cattle today? Surely they aren't fertilizing the grass. Yes, they do. Alfalfa doesn't require a lot of it (it's a nitrogen fixer itself), but other types of grass do. Corn for corn-fed beef certainly needs fertilizer. And corn-fed beef is around 96% of all beef in the US.

myshpa 3y ago
https://ourworldindata.org/land-use-diets https://ourworldindata.org/land-use-diets If the world adopted a plant-based diet we would reduce global agricultural land use from 4 to 1 billion hectares https://www.naturalnews.com/2022-12-09-organic-farming-produces-higher-yields-during-drought.html https://www.naturalnews.com/2022-12-09-organic-farming-produ... Report: Organic farming yields 40% more crops than conventional farming during drought https://www.scientificamerican.com/article/organic-farming-yields-and-feeding-the-world-under-climate-change/ https://www.scientificamerican.com/article/organic-farming-y... A new meta-analysis suggests farmers should take a hybrid approach to producing enough food for humans while preserving the environment https://www.downtoearth.org.in/news/agriculture/farmyard-manure-in-natural-farming-leads-to-higher-yield-than-conventional-method-study-89882 https://www.downtoearth.org.in/news/agriculture/farmyard-man... Farmyard manure in natural farming leads to higher yield than conventional method: Study https://www.nature.com/articles/nature11069 https://www.nature.com/articles/nature11069 with good management practices, particular crop types and growing conditions—organic systems can thus nearly match conventional yields, whereas under others it at present cannot https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0161673 https://journals.plos.org/plosone/article?id=10.1371/journal... Commercial Crop Yields Reveal Strengths and Weaknesses for Organic Agriculture in the United States The analysis we present here offers a new perspective, based on organic yield data collected from over 10,000 organic farmers representing nearly 800,000 hectares of organic farmland. Averaged across all crops, organic yield averaged 80% of conventional yield. However, several crops had no significant difference in yields between organic and conventional production, and organic yields surpassed conventional yields for some hay crops.

jillesvangurp 3y ago

Nutrients are of course required and depleted if you keep harvesting and removing them from the ecosystem. So you need a way to deliver some of that back. There are many ways to deliver nutrients and industrially produced fertilizers are merely one of those. A lot of organic farmers instead use things like compost, crop rotation, and no-till. No till keeps the soil healthy (by not disturbing it) and minimizes nutrient losses through erosion. Compost in the form of carbon rich wood chips or dead leaves, or nitrogen rich greens, or animal waste can do the rest. Certain cover crops actually add nitrogen to the soil. They take nitrogen from the air and deposit it in their roots. When the plants are harvested, the roots remain.

cyberax 3y ago
Gah. Quite a few of nutrients are _dependent_ in nature on erosion. Phosphorus is one of them, it's normally locked in very insoluble phosphates, that get broken down by weathering (erosion). No-till farming preserves nitrogen, which is the main limiting factor in agriculture. It also allows soil to have better water retention. The BIG downside is that no-till farming doesn't disrupt pests, so they can easily crowd out crops. > Certain cover crops actually add nitrogen to the soil. They take nitrogen from the air and deposit it in their roots Yes. That's why people had to leave fields fallow, to allow nitrogen fixing plants (such as clover) to grow and then compost in-place. The problem with that is an extremely poor efficiency of biological nitrogen fixation. It's a wonder that it works at all, honestly.
- myshpa 3y ago
  > That's why people had to leave fields fallow, to allow nitrogen fixing plants (such as clover) to grow and then compost in-place Leaving fields fallow does allow the land to recover and can reduce certain pests and diseases. However, the primary purpose of leaving fields fallow historically wasn't necessarily for nitrogen-fixing plants to grow. That said, some traditional farming systems deliberately planted nitrogen-fixing cover crops, like clover, in rotation with other crops to replenish soil nitrogen. And let's not forget about nitrogen fixing trees. > an extremely poor efficiency of biological nitrogen fixation Biological nitrogen fixation may not be as immediately effective or efficient as directly applying synthetic nitrogen fertilizers, but it's a natural process that has sustained ecosystems for millennia. To say it has "extremely poor efficiency" might be an overgeneralization. In sustainable agriculture, the efficiency of nitrogen-fixing plants isn't solely measured by the speed or volume of nitrogen delivery but also by the myriad of other benefits they provide, such as improving soil structure, suppressing weeds, and promoting beneficial soil microbes. > It's a wonder that it works at all Biological nitrogen fixation is a well-established and crucial ecological process.