The collection of comments have made for interesting reading. I love the fact that a lot of the ideas are coming from different directions and points-of-view, but the exchange has been kept civil.
Very interesting is the real world experiment set up by NiteOwl's father. Regardless of the actual cause for the difference in crop yields (nitrogen, nitrogen depletion, erosion or no), I love the fact that he set the experiment up and had the patience and commitment to sacrifice a growing season to test a deduction. He was obviously onto something as he has successfully improved his yields. Kudos to him for his powers of observation, deduction and curiosity.
It would be an interesting follow-up to test the soil from the two types of fields to see what the real chemical difference are. This would eliminate the off-site hypothesizing and references to questionable reports, a point that both Ann and NiteOwl seem to agree on. That common point is of course, that data and reports provided by large companies (or entities since NiteOwl included the government) are largely suspect and most likely skewed for an ulterior motive. (I think most of us can most likely agree with this point.)
I don't believe anything from the federal government. Too many professional liers (politicians) there and DuPont is another one of those big chemical companies looking out for their bottom line. In this case, I'm sure DuPont intends to make a tidy profit from their biofuel project, so any claims they make supporing it should be taken for propaganda. I believe what I see with my own eyes or in this case my dad's.
Here are a few sources of good information:
Corn Stover to Sustain Soil Organic Carbon Further Constrains Biomass Supply
NiteOwl, here's the USDA on the subject, saying that removing residues (he seems to mean at least corn cobs) does not negatively impact soil via sediment loss: http://www.zimmcomm.biz/domesticfuel/weinhold1.MP3And I'm not sure how "Northern states" are defined by Monsanto or where your dad's farm is. DuPont's facility, and the farmers, are in Iowa. A lot of people there seem to think this is appropriate, at least for that state. They've already tested it in a pilot program of 50 farmers: http://biofuels.dupont.com/cellulosic-ethanol/feedstock/corn-stover/ Also, I'm not the one originally making this claim: it's originally DuPont's: see the links we gave in the article. Note that DuPont's program does leave small amounts on the field to prevent erosion. But in larger quantities, they say it will leach nitrogen. They know more about this than I do. But that was my experience with many of the similar, fibrous mulches gardeners used to use to prevent erosion and, in dry states like California, to preserve soil moisture. Perhaps the answer lies at least partly in how much is removed.
The conculsions of my dad's expermiment were that stover removal is detrimental to the soil as evidenced by the following year's plant growth. Dad said you could see a difference to the row where stover was removed. As I mentioned, the top soil is thin in Southern IL. We had 6 to 8 inches of top soil compared to 3+ feet in the Springfield, IL area. The soil in North/Central IL could support stover removal with little noticable effect for several years, but that is not true everywhere.
Nowhere have I found legitimate information that supports your claim that stover leaches or removes nitrogen from the soil. I have found lots of information that states that nitrogen leaches out of the stover itself as it decays while laying on the ground, but it retains a significant amount of nitrogen that would be lost if the stover is removed. It was my dad's guess based on 50+ years of experience that lower nitrogen levels, where the stover was removed, was the cause of the shorter, less-green corn plants. He should know, since he consistently raised the highest yielding corn in the area and had learned to read the soil and the crops.
Thanks for the additional detail, but it's not clear what the conclusions of your dad's experiment are. If there was little soil erosion or difference in pests, what does he think made the crop shorter and less green? You didn't actually say that removal of stover affected soil nutrients, but It sounds like you're implying that. True?
Monsanto may not have been promoting any of their products, but companies that large in consumer-facing industries (food, drugs) don't publish anything that isn't produced and checked by PR/marketing departments, not to mention legal departments, especially if they've already been sued. I wouldn't trust anything Monsanto or a Big Pharma company said about their industries. In this case, what Monsanto apparently said about stover and nitrogen--according to your summary--was just plain wrong.
My dad fertilized the entire field as he normally would. He did not use additional fertilizer to replace the removed corn stover. The point of the experiment wast to see how much impact, if any, the removal would have. Minor soil erosion was evident, but it was not substantial since there was a small amount of decayed stover from the previous year. No difference in pests was noted. The top soil in Southern Illinois is thin and any changes that affect soil nutrients becomes apparent quickly. Northern Illinois has a lot of top soil, so the same effect would take years to be noticed. Harvesting of corn stover must be carefully managed and may not be possible in certain areas. Another factor is crop rotation. Farms that use a corn-soybean rotation can tollerate less stover removal.
I realize Monsanto is a chemical company that produces pesticides and herbicides, but they do actually produce some accurate and helpful articles concerning topics not directly related to their products. In this case, they were not promoting any of their products.
NiteOwl, not all mulches are created equal. Some, like corn stover, may act well as a mulch, to prevent erosion, but leach nutrients out of the soil. Others don't leach nutrients, but harbor pests and bacteria. All of these were mentioned in the article as reasons for removing the stover. In fact, mulching is no longer as highly recommended as it was when I learned all this in organic vegetable gardening and composting, which I practiced regularly for 10 years during the 70s in a 300-square foot plot in the hills of Northern California. (What you put into compost needs to follow somewhat similar rules.) I understand that a commercial crop has somewhat different requirements, but they don't have to be as different as some think: I currently live in one of two areas in the country where organic gardening & farming was invented--or rediscovered--in the 60s and 70s. Adding nitrogen and/or fixing it in the soil is quite well understood in organic G&F. For example, one of the best ways to do this is to plant a cover crop, such as a legume, that adds it back into the soil. And BTW, I don't trust anything Monsanto says about plants, any more than I would trust drug companies to tell me the truth about their products. In addition, if corn stover was such great cattle feed, I guess that means all of those farmers that signed up with DuPont don't run cattle. Also, you didn't say whether your dad put on something else to replace the corn stover, or what exactly caused the difference: nutrition? bacteria and pests? soil erosion? Details make the difference.
According to an article from Monsanto titled "Excess Corn Stover as Cattle Feed Substitute", excess corn stover is only a problem in colder northern states. The current method of handling this is to chop or shred the stover to enhance decomposition. The stover is very important for reducing soil erosion and for reincorporating organic matter, nutrients and nitrogen back into the soil. It also helps hold moisture and nutrients in the soil, which improves crop yields. Another factor is soil erosion. If even 60% of the stover were harvested from these northern corn fields, those farms would be out of compliance with soil conservation regulations. Instead of chopping or shredding the stover, some farmers choose to feed the excess stover to cattle instead of feeding more exspensive grains, so there are already good uses for excess corn stover.
My father conducted an experiment several years ago where he harvested corn stover from half of a corn field and left the other half untouched. The next corn crop showed a clear difference. Where the stover had been harvested, the corn plants were shorter and not as green as the rest of the field. For the past 5 years my uncle has been harvesting 50% of the stover from his fields and selling it as cattle feed. His corn yields have been steadily decreasing each year as a result.
I'm concerned that large scale removal of corn stover for fuel production will result in poorer crops and higher costs for corn farmers in years to come. Corn production has already come under fire for long term sustainability concerns. DuPont's efforts might be better spent on something else.
Thanks, Tim, for weighing in about local farmers, and the very real need to haul away corn stover. Harboring pests and leaching nitrogen form the soil are very real problems in agriculture--or gardening, which is one of things that attracted me to reporting this story.
@Ann: My point isn't that biofuel production is hamstrung by regulation; in fact, it's just the opposite: federal law (enacted, incidentally, during the supposedly "free-market" Bush Administration) has mandated biofuel production in excess of what the market can accomodate.
I agree that we can and should learn from other countries; on the other hand, with the exception of Brazil, no other country has dived anywhere near as deeply into biofuels as the U.S. In fact, the European Union recently decided to limit food-based biofuels to no more than 5% of transportation fuel. The U.S. government requires a minimum rate of biofuel useage that is more than double the E.U.'s maximum rate.
(By the way, there are some very specific reasons why sugarcane ethanol makes sense in Brazil: Brazil has a tropical climate, an advanced agricultural industry, and lots of arable land. It also has a large automotive industry; most vehicles used in Brazil are manufactured in Brazil, are built as flex-fuel vehicles, and have been for decades. There are few other countries in the world that have all of these advantages).
Of course, the new E.U. limit applies to food-based biofuels only. I agree that replacing corn-based ethanol with cellulosic ethanol makes sense. I hope that DuPont's production of 30 million gallons of cellulosic ethanol at this pilot facility will be offset by somebody else producing 30 million gallons less of corn-based ethanol.
Unfortunately, since biofuel production in the U.S. is dictated by the government and not by the market, I doubt that this will happen.
Alternative biofuels and flex-fuel vehicles are definitely important technology needs. On the other hand, we need to ask ourselves whether our goal is to simply to produce and consume biofuels for the sake of producing and consuming biofuels, or whether we are concerned with long-term environmental sustainability. Sadly, government policy up to now has been focused on the former, not the latter.
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