Monoculture vs. polyculture: When the obviously right choice isn’t


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Diversity is a good thing, right? “Respect diversity” ranks right up there with “natural is better.” And both platitudes say that monocultures are bad and polycultures are good. Monocultures are the standard way to grow commodity crops, but it’s voguish for the small/local/organic/biodynamic crowd to talk about the benefits of crop diversity. It’s pretty obvious that a diverse, natural, “wild field” mix is better for a cover crop in a rotating field system or between vine rows than planting just one thing.

The problem with obvious things is that they’re sometimes wrong. Not because they’re “common knowledge” instead of scientifically tested – plenty of old wives weren’t idiots – but because they rely on stereotypes that don’t work when you stop to think them through.

Andrew McGuire at Washington State University’s Center for Sustaining Agriculture and Natural Resources recently published a pair of blog posts (here and here) knocking down the sensible-sounding idea that mixed cover crops are better than carefully selected monocultures. “Better” here means “deliver more ecosystem services,” and ecosystem services are things like improving soil quality, attracting beneficial insects, and fixing soil nitrogen. He reviews a pile of research demonstrating that different cover crop species are best for each of these different services. When you mix them you don’t get more of everything, as you might expect; you just dilute each of their effects. In other words, mixes are great if you want a little nitrogen fixing, a little flowering for beneficial insects, and moderate biomass to fold back into the soil. But, you can’t cheat the system, plant five different species, and expect to reap the full benefits of all five; you’ll just get a little of everything. The more aggressive species in the mix will also out-compete the less aggressive species – your mix won’t remain a nicely balanced mix forever – and the resulting biomass (the mass of plants to be turned under to enrich the soil) will be lower than what the most vigorous species in the mix would have given you on its own. “Transgressive overyielding” – the idea that plants grown in mixtures benefit symbiotically from each other’s presence and outperform plants grown in monoculture – isn’t supported by the data.

Read more…

 

In transition

This isn’t really the Wineoscope, at least not as it was or as it will be. This is an awkward in-between creature that exists only while I’m getting my act together around a new site. So, please accept my apologies for this pimply adolescent phase, and look forward with me toward something a little less, well, awkward.

The perfect Thanksgiving pairing (has everything and nothing to do with the wine)

My favorite Thanksgiving pairings are pinot noir with Burgundian leanings and sparkling brut rosé. (I’m not aiming for points on originality here). Since I’m a member of the drink-American-on-Thanksgiving club, the pinot noir is likely to lean Burgundy without actually being so in the form of an Oregon pinot noir that remembers that Oregon isn’t California. The sparkling is likely to be Schramsberg if I can get it and Ch. Ste. Michelle if I have to share. That being out of the way, my favorite Thanksgiving pairings have everything and nothing to do with what’s in the bottle.

Growing up, dinner came in two general forms. “Dinner” was eating. I was sometimes allowed to bring a book to the table (don’t judge), my parents talked about business or watched the evening news, and we didn’t have wine. “Nice dinner” was dining. We lit candles. We had wine. The conversations were longer, more thoughtful and, silly or serious, involved more stories. “Dinner” could be over in 45 minutes. “Nice dinners” sometimes took three hours. I blame the wine.

Thanksgiving (and Christmas) was the paragon “nice dinner:” just the three of us, the nice plates, and a meal that took most of the day and a spreadsheet to prepare — because what is Thanksgiving but an excuse for excessively social cooking for a family that doesn’t watch football and does own three mortar-and-pestle sets? And definitely wine. We sometimes thought about a movie afterwards, but as often as not we just talked and listened to music until everyone was warm and sleepy and full of pumpkin pie and single malt and ready for bed. Again, I blame the wine. And the single malt, but mostly the wine.

Thanksgiving and nice dinners have everything to do with science and science communication. I remember the evening when my father first explained color spaces (a fundamental element of color theory) to me. I was somewhere in the second half of my teens and I’m pretty sure the bottle on the table was a Dr. Frank merlot from New York’s Finger Lakes, because that was our house red at the time. We talked about F-stops or the zone system, how sub-woofers work, the finer points of gardening or birdwatching. Later, we talked about my research and I practiced science communication on my father, for whom “cell” was more likely to refer to a battery than a bacterium. Sometimes we were mundane and just rehashed old stories. We always talked about the wine at least a little.

I’m sure that I would have been interested in science and communication and maybe even in wine without those dinners. But “nice dinners,” and holidays especially, were the crystalline form of the stuff that taught me to be inquisitive, to value good conversation (and to hold up my end), and to understand why wine isn’t just about flavor and definitely doesn’t need to be about prestige. Good wine meant good conversation, and good conversation means everything.

I’m all in favor of thoughtful wine and food pairings that reveal exquisite and otherwise-unseen elements of each, or even simply pairings that taste good. But the absolute best pairing with Thanksgiving is just wine, whatever wine makes space for conversation, whether at a quiet table for three or a potluck affair for thirty. Because that, not an exquisite flavor experience, is the wine’s real job.