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A Niche at the Edge of the Crop Circle
September 9, 2013 5:06 AM   Subscribe

How do farmers deal with wasted acreage at the corners of their crop circles? Some add corner systems, so water sprayers can reach the otherwise untouched land at the edges of the sprayers' reach. But as Edible Geography points out, "ecologists are preaching the potential of pivot corners. In a simplified landscape of monoculture crop circles, the corners can restore complexity: left as native perennial grassland or managed as early successional habitat, these concave triangles can provide valuable habitat for bees, birds, and predatory insects to support crop pollination and natural pest control." A short look at the costs and benefits of pivot discards.
posted by MonkeyToes (25 comments total) 16 users marked this as a favorite

 
I was going to suggest putting an artist's signature in the bottom right corner - maybe a little flying saucer or a goofy alien - but then I read TFA and realized it's not that kind of crop circle.
posted by Dr Dracator at 5:14 AM on September 9, 2013 [8 favorites]


That is interesting. Thanks.
posted by Miko at 5:21 AM on September 9, 2013


Interesting topic! Seeing arrays of circular farms from the air always made me wonder why they didn't at least use triangle packing to try to minimize the wasted land.

Evidently the grid structure is imposed by the land registry system, which isn't really a good reason, but at least now I know the explanation.
posted by ceribus peribus at 5:23 AM on September 9, 2013 [3 favorites]


I have to say it's really weird flying over irrigated farmland, looking down and seeing all these circles sitting it rows. It's just something you don't notice from the ground. There's always been a lot of geometry in farming (hell, farming may have created the need for geometry), but it's easy to forget.
posted by GenjiandProust at 5:23 AM on September 9, 2013


The bulk of the USA's productive grain-growing cropland is in the Midwest, where irrigation is not the norm. The wheat lands west of the hundredth meridian are mostly un-irrigated as well. A question which is often asked but difficult to answer: is it worth it, from a tax-payer's vantage point, to grow government-subsidized water-hungry crops in arid regions?
posted by Agave at 5:41 AM on September 9, 2013 [7 favorites]


Evidently the grid structure is imposed by the land registry system, which isn't really a good reason, but at least now I know the explanation.

Well, it was a decent reason given that it was done prior to the development of irrigation booms and computers to do stuff like irregular tessellation. The township system has the advantage of explicitly setting aside public lands for things like schools, which is probably responsible for the perpetuation of universal primary education in the United States.
posted by monocyte at 5:42 AM on September 9, 2013 [5 favorites]


See also Pe'ah for a different take on field corners, (from a different time and agriculure!)
posted by lalochezia at 5:49 AM on September 9, 2013 [6 favorites]


lalochezia, I immediately thought of that as well.
posted by gauche at 5:56 AM on September 9, 2013


Evidently the grid structure is imposed by the land registry system, which isn't really a good reason, but at least now I know the explanation.

In many places, it's not even true squares -- it's a grid, projected onto a sphere, so the "squares" are trapezoidal with two curved sides. On the scale we're talking though, they can be treated as squares -- see why for 75% of the Earth, the Mercator Projection is just fine.

The bulk of the USA's productive grain-growing cropland is in the Midwest, where irrigation is not the norm.

Actually, there is a fair amount of irrigation, but it's simply a matter of moving plentiful surface water to a better spot. Most of it is in various floodplains of the Mississippi/Missouri/Ohio watershed, and they'll pump water up from the river in the dry summer to water the crops as needed. Sometimes the lesser streams will fall too low, but it's very rare for the Mississippi, Missouri or Ohio to drop so low that they can't get water to the floodplain farms.

Even the Ancient Egyptians, who lived in the Nile floodplain and depending on that flood, irrigated -- they would dam in floodwater into reservoirs and release it through the summer to water the crops. This was why a failed flood was so devastating. The floodplain was still fantastically fertile even without the annual renewal of soil, but without the stockpile of water, the crops failed, and if there were 3-4 failed floods, truly devastating famine would occur. The reason that some form of government endured for so long in the Nile Valley was the granaries that such governments could support. About one in ten floods would be significantly lower than, but granaries storing excess crop meant people ate that year. There were times where the flood failed dramatically for several years in a row, and those were very bad times for the Egyptians.
posted by eriko at 6:31 AM on September 9, 2013 [5 favorites]


There's an old Irish tradition of leaving one corner of the field uncut to allow the hare to escape into it. The "hare's corner". In most places the tradition is no longer honoured. The hare population is on the wane, but most likely for a variety of reasons.
posted by distorte at 6:43 AM on September 9, 2013 [9 favorites]


And if you are getting land subsides you can call these unused areas your "set aside" acres and be paid to not grow crops where you had no intention to grow crops. Or at least this was how a farmer once explained it to me. He had areas too wet to plant, so those went into "set aside," areas along the fence line where he had his irrigation lines, the pivot corners, and the other unusable areas he got a check for not using. Who knows, maybe he was pulling my leg, maybe he was a fraudster, but when he was explaining this stuff it seemed like "farming as usual."
posted by cjorgensen at 7:02 AM on September 9, 2013 [2 favorites]


This is fascinating. Thanks.

The economics of the corner systems are interesting. It seems to nearly double the price of a pivot system but only adds around 20% more to the irrigated area. I love the idea of leaving the corners fallow for the critters.
posted by ob1quixote at 7:21 AM on September 9, 2013


these concave triangles can provide valuable habitat for bees, birds, and predatory insects to support crop pollination and natural pest control

I had a work-study job one summer in college on an ecologist's project. One plot was a standard soybean field managed with pesticides. The others were variations in which he'd leave rows of wild plants running through the soybeans as funnels for birds and predatory insects who'd then eat the soybean pests, with no use of pesticides. Our job was to crawl down the rows in the mornings and sample the soybean plants to estimate insect leaf damage. He'd been running the project for a few years and the results were showing that whatever loss in productivity there was from the initial "set-aside" land for the wild plants was made up for by the decrease in insect damage that came from funnelling in the critters that ate the soybean pests. Without pesticides.

Aside from being routinely divebombed by mockingbirds, it was a pretty good job.
posted by mediareport at 7:41 AM on September 9, 2013 [16 favorites]


cjorgensen, I'm 1/5th owner of a very small plot of timber land. We used to get a very small check (about $250, or about $50 apiece) for essentially agreeing with the government that we were not going to do various things to develop the land that were not economically feasible in the first place. Soon after I became the treasurer/form filler-outer I suggested we stop simply because of the paperwork burden on our end, and the potential cost of complying with an audit - not that I thought an audit would find against us, just that it could become time-consuming.

I doubt he was pulling your leg, and doubt he was committing fraud, at least individually. That is to say, I think these programs on the whole are boondoggles, but I imagine what he was doing was entirely within the rules of the game.
posted by randomkeystrike at 7:42 AM on September 9, 2013 [2 favorites]


Leviticus 19:9. And when ye reap the harvest of your land, thou shalt not wholly reap the corners of thy field, neither shalt thou gather the gleanings of thy harvest.
posted by sourwookie at 7:44 AM on September 9, 2013 [6 favorites]


Hey mediareport, I too had a summer job once involving pesticides and center-pivot corn fields in Texas. I had to take dogs out into them looking for dead birds. I found the whole experience horrifying, as you lose all sense of place and positioning when you are on the outside, and then you go in, and try to come back out, and you have no idea where you are.

Was a much better job in the soybean fields of Kansas.

Anyway, the corners on these fields were just bare prairie, nothing special. Only thing I ever recall seeing in them were hordes of 4.5 inch long grasshoppers. Bees would seem to be a great idea, if it weren't for all the pesticides and herbicides.
posted by Windopaene at 9:29 AM on September 9, 2013


Leviticus 19:9. And when ye reap the harvest of your land, thou shalt not wholly reap the corners of thy field, neither shalt thou gather the gleanings of thy harvest.

I'm going to start telling people in my most "I know all about history" voice that the round farm fields were developed as a loophole to avoid having to comply with that passage of scripture.
posted by The World Famous at 9:43 AM on September 9, 2013


"...if it weren't for all the pesticides and herbicides."

This is the problem. You can leave the corners planted with hay or native grasses (or around here, little wild rose bushes), but if you nuke the circular field every year with pesticides and herbicides, it's going to spill into the corners and leave them barren.
posted by Kevin Street at 1:43 PM on September 9, 2013


Hey mediareport, I too had a summer job once involving pesticides and center-pivot corn fields in Texas. I had to take dogs out into them looking for dead birds. I found the whole experience horrifying

Remind me to tell you about the work-study job I once had perfusing the brains of rabbits, then cutting off their heads, cracking their skulls open and removing the brains so they could be frozen and sliced to compare the slides against the recorded activity in the electrodes that had previously been inserted. I eventually got them to let me switch to cleaning the shit out of the rabbit cages. Much less traumatic.
posted by mediareport at 2:11 PM on September 9, 2013


(In case I didn't make it obvious enough, I had to inject poison into veins in each rabbit's ear to kill them before I used their still-beating hearts to force saline through the arteries in their brains so the slides would be clear.)
posted by mediareport at 2:15 PM on September 9, 2013


Yay. You've discovered hedges.
posted by Hugh Routley at 7:53 AM on September 10, 2013


Hugh Routley: "Yay. You've discovered hedges."

No, hedges are simply living fencelines.... at least, I've never heard the word used to describe a large polygon of land left fallow.
posted by IAmBroom at 12:21 PM on September 10, 2013


That is a good point about hedges, though. They do tend to be oases of biodiversity in otherwise monocultural landscapes - to the point at which they have their own ecosystems. I think the comparison is very valid. Stone walls have a similar effect. (I used to teach in an environmental education and doing life inventories in succession zones and in stone walls was enough to prove to myself, and our students, that they are havens for a greater diversity of species than can survive in farm field or meadow.)
posted by Miko at 2:07 PM on September 10, 2013


Are they really? I'm not accustomed to hedges showing that much species diversity. The ones that aren't monocultures themselves (like the boxwood out front of my condo) simply have a few weeds poking out of them (like our hedges out back, that no one sees) - but nowhere near the biodiversity I can find in 10 square meters of a neighbor's lawn that is only mowed once a year.
posted by IAmBroom at 6:48 PM on September 10, 2013


Yes, they are really. I'm not sure what's doubtable about my own evidence of having done some hedge inventories myself, but here are some other sources to look through: Plant TNT: Hedgerows, Wildlife and Hedgerows, Landscaping for Wildlife: Trees, Shrubs, and Vines, Dry Stone Walls and Wildlife, another Dry Stone Walls and Wildlife, and Shrubs for Wildlife.

Of course, I'm talking about hedges out in fields - the long borders between cultivated fields. They harbor plant, insect, mammal, avian and often amphibian life and create cover for small birds and mammals that eat seeds/fruits in the fields, and thus attract larger predators like hawks and foxes at certain times of day. Your neighbor's lawn, untended, is more analogous to that sort of hedgerow than it is to a monoculture farm field or to an isolated suburban hedge.

Yet, I suspect if you conducted a thorough analysis of even a suburban boxwood hedge, you could document a good dozen species. You need to spend a good deal of time observing at different times of day and ight, and also to crawl under them and sift through the leaf litter and top layers of soil, as well.
posted by Miko at 7:56 PM on September 10, 2013 [2 favorites]


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