2016/02/22

Grow Food Organically or Not?

Here are some excerpts from two articles, "Amish Farmers Reinventing Organic Agriculture" and "War Between Organic and Conventional Farming Misses the Point".
Let's talk about some of the issues involved in growing our food!
As always, the titles of the sections are links to the original article.

War or Peace?
“In the Second World War,” Samuel Zook began, “my ancestors were conscientious objectors because we don’t believe in combat.” The Amish farmer paused a moment to inspect a mottled leaf on one of his tomato plants before continuing. “If you really stop and think about it, though, when we go out spraying our crops with pesticides, that’s really what we’re doing. It’s chemical warfare, bottom line.”

Immune System

A series of crop failures on his own farm drove the 8th grade-educated Kempf to school himself in the sciences. For two years, he pored over research in biology, chemistry, and agronomy in pursuit of a way to save his fields. The breakthrough came from the study of plant immune systems which, in healthy plants, produce an array of compounds that are toxic to intruders. “The immune response in plants is dependent on well-balanced nutrition,” Kempf concluded, “in much the same way as our own immune system.” Modern agriculture uses fertilizer specifically to increase yields, he added, with little awareness of the nutritional needs of other organic functions. Through plant sap analysis, Kempf has been able to discover deficiencies in important trace minerals which he can then introduce into the soil. With plants able to defend themselves, pesticides can be avoided, allowing the natural predators of pests to flourish.

Roc Morin: One thing that I immediately noticed is how great everything smells here. Do you still smell it, or are you accustomed to it?
Samuel Zook: Oh, I smell it every time I come here. It’s exciting. Those aromas are actually compounds the plants produce to defend themselves from insects and disease attacks. A lot of people don’t realize that plants have immune systems.
Morin: So, you can smell health—can you can smell problems too?
Zook: Yes. There’s a real science to walking through a field and pausing to feel what the plants are feeling. There’s a huge difference between walking in this field and walking in one that has had six fungicide applications. The plants just don’t radiate that same vitality. Another thing I learned is that every time you spray with a fungicide or something, it’s actually suppressing the plant as well as the fungi.
Morin: The same way that antibiotics can weaken a person’s immune system?
Zook: Yes. It might kill the disease, but then because it has weakened the plant, a week later the plant is much more susceptible to that same disease again. That’s the way it is with miticide. If I come in here and spray the mites with it, it would kill some of them, but it kills by messing with their hormones, so the ones that do survive will then mature 50 percent faster. So, it’s pretty much guaranteed that I’d have a huge mite outbreak 10 years later. Instead of doing that, let’s figure out what this plant wants and provide it. They really do respond.

Healthy Ecosystem = Healthy Plants
Morin: Can you describe the differences between how you used to farm and how you farm now?
Zook: The inputs changed drastically. Instead of trying to grow crops that are healthy with fungicides and pesticides, I started to grow crops that are healthy with nutrition.
Morin: What was the hardest part about making the change?
Zook: Well, there was a big psychological block that I had to get through. I’d see a couple bugs out there and feel like I immediately had to do something about it. But, I learned that if I sit back, things will often take care of themselves. That first summer for instance, we saw a lot of horn worms. Before that, I would have sprayed them right away, but this time I waited and a bunch of wasps came along and killed them. Once I saw that, I started getting really excited.
Morin: So, when you use a pesticide you’re killing the predators too, right?
Zook: Right. You’re killing the entire ecosystem.

Morin: How do you get [insects] under control?
Zook: Mainly through applying specific trace minerals like iodine and a whole line of ultra-micronutrients. We analyzed the sap of the plants with the help of a lab and I think we’ve narrowed the problem down to excessive ammonium nitrates. If ammonia builds up in the plants, it’s bug food, so we need to figure out a way to convert ammonia fast. I just spent two days with John [Kempf], and he came up with an enzyme cofactor which we’ll use to stimulate that ammonia conversion. We figure things out ourselves now rather than call up the chemical rep.
Morin: What did your chemical rep say when you told him that you didn’t need his services anymore?
Zook: Well, that was an interesting summer. He used to come here every week telling me horror stories about all the diseases in the neighborhood. But, I had made up my made up my mind, “No mas.” He came back every week for eight weeks telling me what I needed to spray. I said, “I’m fine, thanks.” The last time he was here, we were out picking tomatoes and he walked over. He was looking around and talking about this and that, and he didn’t even mention pesticides. “Well,” he said, “your tomatoes look pretty good.” I thought, “Yes!”

Yield is not the only factor
Yield [the amount of vegetables or grain produced by a field] is "...only part of a range of economic, social and environmental factors that should be considered when gauging the benefits of different farming systems."

This point is often overlooked in discussions of how best to feed the world. Farming methods impact the lives of all who share the ecosystem. They can pollute the environment or make use of what would otherwise have become pollutants. They can affect the nutrient levels in food and the health of farm workers. To assume that the best farming practice is the one that produces the highest yield is like observing that a Lamborghini outraces a bicycle, and thus should be the world's only vehicle.

When is it appropriate to use pesticides and fertilizers?
The paper asserts that the efficacy of various farming systems is context-dependent, and proposes that the apparent dichotomy between organic and nonorganic is overly simplistic. Hybrid systems, the paper suggests, should be considered in some contexts. Ramankutty used his personal approach to food procurement as an example of how a hybrid system might work.

"I often buy organic food," he told me. "Partly it's because of some maybe nonscientific fear of pesticide residues in food -- although it looks like scientific evidence for that is not hard to get.
"On the other hand, I wouldn't mind if a farmer was applying a little bit of chemical fertilizer. I may not buy food if somebody was applying pesticides, but I would certainly not mind if my farmer applied a little bit of chemical fertilizer on his farm. It's when we use 200 kilograms per hectare compared to maybe 40 or 50 kilograms that the problem arises."
The paper notes that many organic agriculture systems are deficient in nitrogen, and that production on such farms would benefit from more of it. But most conventional systems have more than enough nitrogen, thanks to the ease and cost of applying chemical fertilizer.
"The problem we have with nitrogen is that we use too much of it, in some parts of the planet," Ramankutty told me. "Then it gets left behind in the soil, it leaches out into groundwater, causing water quality problems. It runs down rivers and into lakes and causes algal blooms.
"There's a diminishing return to nitrogen application. If you're applying more and more fertilizer, plants take up less and less of it. If nitrogen is heavily subsidized, that is if there's no cost to applying nitrogen, then farmers won't have any incentive to reduce the amount of nitrogen."