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Is it possible that the soil is also depleted of interesting nutrients and that the fertilizer isn't providing them either? Our understanding of what micronutr

Is it possible that the soil is also depleted of interesting nutrients and that the fertilizer isn't providing them either? Our understanding of what micronutrients humans need is not great. For plants, it may be even less understood.

mikekchar 8y ago
Depending on what you mean, either yes or no :-) This is based on my poor understanding of the situation. Someone who is knowledgeable will hopefully be able to correct me. I think there are actually plenty of nutrients in soil (even many "poor" soils). The real problem is that they aren't bio-available. So you'll have lots of different mineral salts in the soil (usually one or two orders of magnitude more than you need, by weight), but it's not in a form that the plant can absorb by its roots. I think the real problem is the kind of mono-culture cropping we do. Really you want a variety of plants pulling up nutrients out of the ground (because different varieties have different abilities to break down and convert the nutrients in the soil). Then you want those plants to break down and be reintegrated in the soil. Finally, you often want some of that happening in an anaerobic environment, so you don't bind oxygen to it. There are some new (old? ha ha) techniques being developed to build fertility (really just making existing nutrients bio-available) in the soil. Avoiding tilling, building up micro-organisms and insects to distribute the soil, allowing a variety of plants to grow (some long roots, some short roots, etc, etc). It's pretty complicated, though and I expect that it will take us a very long time to learn how to do these things effectively. It definitely seems easier to just add what you think the soil is missing, but there are many disadvantages to that approach as we see over time. I did some experiments in containers a while ago. My idea was to see what kind of production I could get without adding any inputs to the soil at all (just water), and harvesting as much food as I could. I had some experience from doing planted fish tanks with really intense planting (every single space possible occupied with a plant) and knew that it was reasonable to assume that plants can grow really well being very crowded as long as nutrients are available. I planted my containers so that light was the limiting factor, but grew a lot of local weeds that grew in poor soil as well as food on the assumption that they would build fertility fastest. I ran my experiment over 5 years and was really surprised at my results -- my production increased over time. One year, I even got 5 (!) harvests of potatoes from the same container -- I've never even come close to that level of production doing it more traditionally. It was all very unscientific and I was really doing it out of curiosity more than trying to prove anything. In the end, it seems my neighbor didn't like my container garden of weeds and he convinced my gas man to apply herbicide to it. That was the end of my experiment (I caught him in the act as I came home from work a little bit early that day -- one of the few times I've really blown my top). Anyway, I don't think we really have to worry over much about actually depleting our soils. I think they can rebound fairly quickly with the right approach. However, I think it is possible that our current intensive farming approaches do not produce the most nutrient rich produce possible.
- agsdfgsd 8y ago
  >Really you want a variety of plants pulling up nutrients out of the ground (because different varieties have different abilities to break down and convert the nutrients in the soil) That doesn't appear to be needed. The plants don't have the ability at all, the microorganisms they attract and feed do it. You can build fertility while growing a single crop year after year, Fukuoka did rice and wheat every year for decades on the same land just fine. As long as you keep the microorganisms fed and don't insist on a program of routinely killing them, they'll break down the minerals that the plants need and make them available. >Finally, you often want some of that happening in an anaerobic environment, so you don't bind oxygen to it. No you don't. When it happens in an anaerobic environment you get end products that hinder plant growth instead of helping it. This is the main reason soil compaction is a problem, you get pooled water in the ground creating anaerobic conditions which kill off all the good bacteria and fungi.
  - mikekchar 8y ago
    > Fukuoka did rice and wheat every year for decades on the same land just fine. Fukuoka also used wild carrots and daikon to bring up nutrients from lower down (source: My friend studied with him). Also white clover to fix nitrogen (and even went so far as to say, "Don't bother experimenting with anything else. I've tried everything and white clover is the best."). Rice is a summer crop and in most places in Japan you can have a winter crop as well, which you use for nutrient migration. Fukuoka's techniques work very well around where I like (my friend's fields are fantastic), but apparently don't work very well in more temperate climes (just from what I've heard).
    - agsdfgsd 8y ago
      >Fukuoka also used wild carrots and daikon to bring up nutrients from lower down (source: My friend studied with him). Not according to him he didn't. Read his books, he was very clear about everything he did. He grew vegetables to eat, in a completely different area, it had nothing to do with the grain field. >Also white clover to fix nitrogen Nitrogen is a non-issue precisely because you can pull it out of the air for free. You said you want a variety of plants to pull nutrients from the ground. Clover pulling nitrogen from the air is not support for that idea. >Rice is a summer crop and in most places in Japan you can have a winter crop as well, which you use for nutrient migration. But he didn't do that, he used it for a crop. He did rice and wheat, like I said. Both were crops, he sold the harvests. He did it for decades without any decline in yields. The idea that you need a "diverse polyculture" of plants as the current fad calls it is completely unsupported by evidence. They just need a healthy ecosystem to grow in, not necessarily different plants. >Fukuoka's techniques work very well around where I like (my friend's fields are fantastic), but apparently don't work very well in more temperate climes The techniques and ideas work fine, but you can't blindly copy his setup as it was. You don't have the season for two crops, so you don't do rice and wheat. You just do wheat. Marc Bonfils has grown winter wheat every year in the same field for over a decade with no inputs, no rotation, and yields increased each year as the soil was restored. If you are in a cold enough climate it might even make sense to compost your straw in the spring in order to warm your soil up earlier, but I am not sure about that yet, I'll be testing it this spring.

mikekchar 8y ago

Depending on what you mean, either yes or no :-) This is based on my poor understanding of the situation. Someone who is knowledgeable will hopefully be able to correct me. I think there are actually plenty of nutrients in soil (even many "poor" soils). The real problem is that they aren't bio-available. So you'll have lots of different mineral salts in the soil (usually one or two orders of magnitude more than you need, by weight), but it's not in a form that the plant can absorb by its roots. I think the real problem is the kind of mono-culture cropping we do. Really you want a variety of plants pulling up nutrients out of the ground (because different varieties have different abilities to break down and convert the nutrients in the soil). Then you want those plants to break down and be reintegrated in the soil. Finally, you often want some of that happening in an anaerobic environment, so you don't bind oxygen to it. There are some new (old? ha ha) techniques being developed to build fertility (really just making existing nutrients bio-available) in the soil. Avoiding tilling, building up micro-organisms and insects to distribute the soil, allowing a variety of plants to grow (some long roots, some short roots, etc, etc). It's pretty complicated, though and I expect that it will take us a very long time to learn how to do these things effectively. It definitely seems easier to just add what you think the soil is missing, but there are many disadvantages to that approach as we see over time. I did some experiments in containers a while ago. My idea was to see what kind of production I could get without adding any inputs to the soil at all (just water), and harvesting as much food as I could. I had some experience from doing planted fish tanks with really intense planting (every single space possible occupied with a plant) and knew that it was reasonable to assume that plants can grow really well being very crowded as long as nutrients are available. I planted my containers so that light was the limiting factor, but grew a lot of local weeds that grew in poor soil as well as food on the assumption that they would build fertility fastest. I ran my experiment over 5 years and was really surprised at my results -- my production increased over time. One year, I even got 5 (!) harvests of potatoes from the same container -- I've never even come close to that level of production doing it more traditionally. It was all very unscientific and I was really doing it out of curiosity more than trying to prove anything. In the end, it seems my neighbor didn't like my container garden of weeds and he convinced my gas man to apply herbicide to it. That was the end of my experiment (I caught him in the act as I came home from work a little bit early that day -- one of the few times I've really blown my top). Anyway, I don't think we really have to worry over much about actually depleting our soils. I think they can rebound fairly quickly with the right approach. However, I think it is possible that our current intensive farming approaches do not produce the most nutrient rich produce possible.

agsdfgsd 8y ago
>Really you want a variety of plants pulling up nutrients out of the ground (because different varieties have different abilities to break down and convert the nutrients in the soil) That doesn't appear to be needed. The plants don't have the ability at all, the microorganisms they attract and feed do it. You can build fertility while growing a single crop year after year, Fukuoka did rice and wheat every year for decades on the same land just fine. As long as you keep the microorganisms fed and don't insist on a program of routinely killing them, they'll break down the minerals that the plants need and make them available. >Finally, you often want some of that happening in an anaerobic environment, so you don't bind oxygen to it. No you don't. When it happens in an anaerobic environment you get end products that hinder plant growth instead of helping it. This is the main reason soil compaction is a problem, you get pooled water in the ground creating anaerobic conditions which kill off all the good bacteria and fungi.
- mikekchar 8y ago
  > Fukuoka did rice and wheat every year for decades on the same land just fine. Fukuoka also used wild carrots and daikon to bring up nutrients from lower down (source: My friend studied with him). Also white clover to fix nitrogen (and even went so far as to say, "Don't bother experimenting with anything else. I've tried everything and white clover is the best."). Rice is a summer crop and in most places in Japan you can have a winter crop as well, which you use for nutrient migration. Fukuoka's techniques work very well around where I like (my friend's fields are fantastic), but apparently don't work very well in more temperate climes (just from what I've heard).
  - agsdfgsd 8y ago
    >Fukuoka also used wild carrots and daikon to bring up nutrients from lower down (source: My friend studied with him). Not according to him he didn't. Read his books, he was very clear about everything he did. He grew vegetables to eat, in a completely different area, it had nothing to do with the grain field. >Also white clover to fix nitrogen Nitrogen is a non-issue precisely because you can pull it out of the air for free. You said you want a variety of plants to pull nutrients from the ground. Clover pulling nitrogen from the air is not support for that idea. >Rice is a summer crop and in most places in Japan you can have a winter crop as well, which you use for nutrient migration. But he didn't do that, he used it for a crop. He did rice and wheat, like I said. Both were crops, he sold the harvests. He did it for decades without any decline in yields. The idea that you need a "diverse polyculture" of plants as the current fad calls it is completely unsupported by evidence. They just need a healthy ecosystem to grow in, not necessarily different plants. >Fukuoka's techniques work very well around where I like (my friend's fields are fantastic), but apparently don't work very well in more temperate climes The techniques and ideas work fine, but you can't blindly copy his setup as it was. You don't have the season for two crops, so you don't do rice and wheat. You just do wheat. Marc Bonfils has grown winter wheat every year in the same field for over a decade with no inputs, no rotation, and yields increased each year as the soil was restored. If you are in a cold enough climate it might even make sense to compost your straw in the spring in order to warm your soil up earlier, but I am not sure about that yet, I'll be testing it this spring.