Teach me what the chemfarmers do

I don't have a farming background but live in a predominately farming county.  I need to learn more about what the farmers do and why so I can spar with them a little better.

Around here, it's a bean and corn rotation year after year after year.  I was surprised a few weeks ago when one of the farmers mentioned that he had to fertilize before he could plant his corn.  I always thought that the beans replaced the nitrogen.  He said the beans do but they use it for themselves, therefore, he needs to fertilize... What the heck is the purpose of rotation then? I thought I had read that legumes have nodes that leave nitrogen or am I confused with something else?

Last night I was told the corn stalks left on the field will raise the acidity and so every few years, they need to lime the field.  Is that because no "greens' ever get left?  My favorite sparing partner said that my way of composting in place, will also eventually raise the acidity in my beds. 

I really need to learn as much as I can about what they do and why, so I can sound half way intelligent when I'm combating their practices.

The crop rotation helps to break the pest cycle.  Most corn pests can't survive on soybeans and vice versa so alternating the two crops breaks the pest cycles.

They have to add lime every few years because chemical fertilizers are acidic (they contain sulfuric and hydrochloric acids) and lower soil pH.  It also kills many soil organisms such as earthworms, snails, slugs, and any amphibians (frogs, toads, salamanders) that happen to cross the fertilized field or get exposed to its runoff.  You can pour water containing chemical fertilizers on healthy soil and watch the earthworms quickly emerge from the soil and die.

Composting only produces weak organic acids (humic and carbonic acids) which only very minimally lower soil pH since composting also produces a myriad of organic compounds that absorb and buffer the organic acids that are also produced.

The nodes on the bean roots do add N to the soil if they are left in the soil to rot.  If they are tilled up and left to decay on the surface, much of that N will be lost to the atmosphere.  The N in the nodes is not immediately available to the next crop, as it needs to be digested and converted by the microbes before it becomes available to other plants.  The glyphosphates used to kill weeds, also kills the microbes which are needed to convert that N into a plant usable form, so yes, your neighbor probably needs to add ferts.

Repeated use of synthetic chemical inputs in conventional farming, together with repeated tilling, causes the soil micro-community to crash and die, almost completely.  Once it loses the microbiological diversity, the soil becomes almost helpless to cycle nutrients back to the plants in the normal way.    Thus, the chem farmer has no choice but to add readily soluble chem fertilizers to feed the plants directly.  It's like a doctor putting you on an IV because you just got shot in the stomach.

It "feeds" you, and it "works", but it does not have good long term prospects.

Do a google search for +"humus loss" +corn and you'll get a lot of good info.  Here's one example that pretty thorough and informative:

http://www.wilderness-survival.net/composting/maintaining-soil-humus

One way to debate a traditional chem farmer is to ask them what their humus loss rate is.  Then ask them what their topsoil loss rate is.  If they know those numbers, they will know they just lost the long term argument.  If they don't know those numbers, have a couple resources so you can educate them about topsoil health in the long run.

This whole youtube bbc series about chem farming vs alternatives lays out the problem pretty succinctly without being too heavy handed:

http://www.youtube.com/watch?v=xShCEKL-mQ8


There are 5 or 6 segments of 10 minutes each.

Here's a pdf from a dairy farmer who gets it and is doing something about it:

http://northerngraingrowers.org/wp-content/uploads/theimportanceofbuildinghumus.pdf


I grew up on a chem farm.




HTH,

troy

Solarguy pretty well described long term use of chemicals.  It is a one way road to converting soil into dirt.  Dirt will not grow crops without inputs.

Thank you sooo much for this information. It will help me tremendously.

I'll study up about the humus and topsoil loss in great detail as I know their eyebrows will raise when I bring that up.  (That gives me a secret thrill when that happens!)

I stated that if I tested my soil against the field soil next to my land, that my test results would return much better.  I was asked why I thought that since the field gets fertilized.  My sparing partner thinks they will be somewhat equal.  I know my soil has more life, but could those test results actually be close?

The glyphosphates used to kill weeds, also kills the microbes which are needed to convert that N into a plant usable form...

Do they know this?  Maybe I should ask this way, do the majority of chem farmers know what is happening to their soil with the use of chemicals and either don't care or just don't know any other way?

The crop rotation helps to break the pest cycle.

Since I rarely have pest problems, I hadn't thought about that.  Are there other reasons that they might rotate? 

I remember one evening getting laughed at pretty heartily when I asked if they couldn't interplant beans and corn somehow.  I did recently see a reference somewhere where someone did with alternating and wider spacing between rows, with excellent results.  I know nothing about harvesting equipment, so I'm wondering if this is the most major drawback?  If pests were a problem, would they eventually subside or would another crop thrown into the rotation help in that aspect?

Corn and beans are a natural combination.  It was a part of the 3 Sisters (corn/beans/squash) used by the American natives to provide food for the winter.  In the Basque regions of Spain, corn/beans are also planted: the corn provides a pole for the beans to climb on, as well as providing shade which the beans like.  the bean's thicker foliage helps suppress weeds around the corn stalks.

Probably the reason the combination is not used by commercial farmers is that they rely on machines to do their harvesting.  They would probably have to hand harvest the beans, and the bean harvest would cease once the mechanical corn harvest took place.  If one is willing to hand harvest, an acre's yield can be doubled.  They are using steel and petroleum to save labor, but only getting partial use of their land...ho-hum.

Polyculture almost requires human labor, especially up front to get it established.  They can't imagine finding hundreds of people willing to work for low wages doing hard manual labor.

They are probably right.

Your soil would test orders of magnitude better if you test for the numbers and diversity of soil life.

For testing available nitrogen, the chem farm guy might "win".  Happy soil with plenty of life in it sort of makes the nitrogen available to the plant as needed.  There is generally not a bunch of nitrogen soup laying around in the good soil.

The chemical fertilizers also kill the microbes, as well as adding a LOT of salts to the soil.
The salts alone are damaging the soil, and tieing up nutrients so they cannot be utilized as well by the plants.

Suzie wrote:
I don't have a farming background but live in a predominately farming county.  I need to learn more about what the farmers do and why so I can spar with them a little better.

Around here, it's a bean and corn rotation year after year after year.  I was surprised a few weeks ago when one of the farmers mentioned that he had to fertilize before he could plant his corn.  I always thought that the beans replaced the nitrogen.  He said the beans do but they use it for themselves, therefore, he needs to fertilize... What the heck is the purpose of rotation then? I thought I had read that legumes have nodes that leave nitrogen or am I confused with something else?

Most of the nitrogen that the bacteria fix for the beans goes into the seed, though some will be retained in the leftover residue (leaves, stems, roots), so what he mentioned is correct in a sense, but not the entire story. Also, corn is generally an N-hungry crop and has relatively shallow roots. If he is removing most of the residue of the beans and corn, he is basically robbing away all the nitrogen and starving the soil. Rotation is mainly to disrupt diseases and pests and to avoid exhausting the soil of certain nutrients or micronutrients.

Last night I was told the corn stalks left on the field will raise the acidity and so every few years, they need to lime the field.  Is that because no "greens' ever get left?  My favorite sparing partner said that my way of composting in place, will also eventually raise the acidity in my beds.

That's true to an extent, since some of the residue will be converted to humus and humic acids, which generally have a bit lower pH, but is *ideal* for plants. Generally around 5-6ish to 8 is great for plants, though it depends on the plant or crop and what you have in your soil. What they said isn't noteworthy. A slightly lower soil pH frees up nutrients that most plants need to thrive. You're unlikely to have really low soil pH unless you: (a) live or farm in a peat bog or (b) mulch everywhere with several feet of conifer needles (and there's some debate on whether conifers really do acidify the soil or not, but it's my understanding they do a bit).

They need to lime because they again robbed the soil of its calcium.

I really need to learn as much as I can about what they do and why, so I can sound half way intelligent when I'm combating their practices.

Just focus on what you can do, IMO.