# Most efficient use of land for growing food? **URL:** \ **Category:** Factual Questions\ **Created:** [September 10, 2011, 4:49pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836 "2011-09-10T16:49:17Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![MrBerious](https://avatars.discourse-cdn.com/v4/letter/m/9fc29f/32.png) [@MrBerious](https://boards.straightdope.com/u/MrBerious)\ **Post date:** [September 12, 2011, 6:21pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/21 "2011-09-12T18:21:43Z")
Well poor Irish tenant farmers grew potatoes because that’s all that could possibly support them on their tiny plots of land. [Wikipedia](http://en.wikipedia.org/wiki/Potato#cite_note-26)reckons: > [@](#): > > The yield of Calories per acre (about 9.2 million) is higher than that of maize (7.5 million), rice (7.4 million), wheat (3 million), or soybean (2.8 million). Downside is they go rotten much easier than grains and of course if you’re counting on one crop and it fails or any reason then you’re up the creek. Although for a comprehensive real world answer you’d have to factor in all sorts of other variables. Climate, soil composition, area you’ve actually got to work with, how much do you really like eggs and so forth. Even pigs might make sense if you’ve a lot of food waste to feed them ---
**Author:** ![md2000](https://avatars.discourse-cdn.com/v4/letter/m/73ab20/32.png) [@md2000](https://boards.straightdope.com/u/md2000)\ **Post date:** [September 12, 2011, 8:30pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/22 "2011-09-12T20:30:49Z")
Obviously, the same amount of food calories, grown, harvested then reprocessed as eggs, feathers, dark meat and chicken guano, is going to be less than the same amount of food calories just grown and eaten by a human. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [September 12, 2011, 8:55pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/23 "2011-09-12T20:55:15Z")
nm ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [September 12, 2011, 10:32pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/24 "2011-09-12T22:32:31Z")
> [@md2000](#): > > There was an essay in one of the Malcolm Gladwell books about efficient management of rice paddies in southern China. These guys got to keep much of the profits of their labor unlike his counter-example of French medieval peasants, but they had to apply themselves and micromanage the paddy. In some cases they could expect 3 crops a year, very high yields. Outliers, CH.8, “Rice Paddies and Math Tests”. But everything I’ve read about this indicates that it requires great effort from the Chinese peasants (and their whole family), every day of the growing season, to produce their rice crop. That much human labor doesn’t seem very efficient! Most American farmers, working alone with their mechanized equipment, farm hundreds of acres, and do it part-time! Many (most?) of them also have day jobs, and do their farming work on evenings & weekends. ---
**Author:** ![John\_Bredin](https://avatars.discourse-cdn.com/v4/letter/j/96bed5/32.png) [@John\_Bredin](https://boards.straightdope.com/u/John_Bredin)\ **Post date:** [September 13, 2011, 3:30pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/25 "2011-09-13T15:30:43Z")
Does it have to be unimproved or bare land? Because I would imagine that a multi-story windowless building for growing mushrooms or similar edible fungi would be very land-efficient. Stacked-up mushroom caves, in a sense. Or, if land is _really_ limited but you have other resources, dig or repurpose tunnels to use as mushroom caves while still using the surface for something else. I’m presuming that mushrooms and the like are grown in, essentially, manure. (Correct me if I’m wrong.) Manure is being generated whether or not the mushroom farm is using it so it doesn’t “count” as land use in the same way that growing grain to feed chickens counts as additional land use. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [September 13, 2011, 8:57pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/26 "2011-09-13T20:57:08Z")
> [@John\_Bredin](#): > > Or, if land is _really_ limited but you have other resources, dig or repurpose tunnels to use as mushroom caves while still using the surface for something else. > > I’m presuming that mushrooms and the like are grown in, essentially, manure. (Correct me if I’m wrong.) Manure is being generated whether or not the mushroom farm is using it so it doesn’t “count” as land use in the same way that growing grain to feed chickens counts as additional land use. Just finished the Minnesota State Fair here. The manure from the horse barn is sold to be used in tunnels to grow mushrooms, we have heard. That’s given as a reason that the Fair restricts what can be used as bedding in the horse stalls – only untreated wood shavings are allowed. Theoretically, you could[ul][li]plant corn on your plot of land[/li][li]keep chickens there, to peck for insects around the corn stalks & roots[/li][li]have a tunnel under the land to grow mushrooms[/li][li]collect the chicken manure to use in the mushroom-growing tunnel[/li][/ul] Seems like that would give you 4 sources of food from 1 plot of land: the corn, the chicken eggs, the chickens themselves at the end of the laying season, and the mushrooms. ---
**Author:** ![thelabdude](https://avatars.discourse-cdn.com/v4/letter/t/dc4da7/32.png) [@thelabdude](https://boards.straightdope.com/u/thelabdude)\ **Post date:** [September 13, 2011, 10:19pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/27 "2011-09-13T22:19:10Z")
Manure can also be used to replace part of the mineral fertilizer. Amazing what a mess a simple question has turned into. At least we are keeping it in GQ. ---
**Author:** ![Mangosteen](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@Mangosteen](https://boards.straightdope.com/u/Mangosteen)\ **Post date:** [September 14, 2011, 12:12am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/28 "2011-09-14T00:12:23Z")
Another important factor is irrigation. How many calories are you burning “watering” your chickens or crops? Are you paying someone for the water? On my farm in Hawaii, it rains 150 inches a year and its pretty spread out over the entire year. This “free” water makes growing things a lot cheaper and easier. Another factor is cooking. A potato does no one any good unless its cooked. Are you growing the trees that produce the wood that is used to heat the cooking water? I suppose you can eat raw eggs, but one would have to be pretty hungry to eat raw chicken. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [September 14, 2011, 3:57am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/29 "2011-09-14T03:57:49Z")
> [@Mangosteen](#): > > Another factor is cooking. A potato does no one any good unless its cooked. What? A potato is one of many vegetables that can be readily eaten raw. And for potatoes, there is no significant difference in the ‘digestibility’ or absorbed calories for either raw or cooked. (Though that’s not true for all vegetables.) ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [September 14, 2011, 2:22pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/30 "2011-09-14T14:22:36Z")
> [@t-bonham@scc.net](#): > > What? A potato is one of many vegetables that can be readily eaten raw. And for potatoes, there is no significant difference in the ‘digestibility’ or absorbed calories for either raw or cooked. (Though that’s not true for all vegetables.) Cite? I’ve always heard exactly the opposite: that a potato has no food value unless cooked to break open the cells. ---
**Author:** ![JoelUpchurch](https://avatars.discourse-cdn.com/v4/letter/j/f05b48/32.png) [@JoelUpchurch](https://boards.straightdope.com/u/JoelUpchurch)\ **Post date:** [September 14, 2011, 6:54pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/31 "2011-09-14T18:54:25Z")
> [@Hari\_Seldon](#): > > Cite? I’ve always heard exactly the opposite: that a potato has no food value unless cooked to break open the cells. [http://www.thehotpotato.com/english/nutrition.htm](http://www.thehotpotato.com/english/nutrition.htm) This indicates that the calorie count in a baked and raw potato are the same. Actually it looks like a baked potato would be an excellent item for a diet if I left off the butter, sour cream and sauteed mushrooms. 🙂 ---
**Author:** ![davidm](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/davidm/32/225_2.png) [@davidm](https://boards.straightdope.com/u/davidm)\ **Post date:** [September 14, 2011, 8:36pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/32 "2011-09-14T20:36:26Z")
How about high-rise farming? [http://www.verticalfarm.com/more](http://www.verticalfarm.com/more) > [@](#): > > The concept of indoor farming is not new, since hothouse production of tomatoes, a wide variety of herbs, and other produce has been in vogue for some time. What is new is the urgent need to scale up this technology to accommodate another 3 billion people. An entirely new approach to indoor farming must be invented, employing cutting edge technologies. The Vertical Farm must be efficient (cheap to construct and safe to operate). Vertical farms, many stories high, will be situated in the heart of the world’s urban centers. If successfully implemented, they offer the promise of urban renewal, sustainable production of a safe and varied food supply (year-round crop production), and the eventual repair of ecosystems that have been sacrificed for horizontal farming. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [September 14, 2011, 10:03pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/33 "2011-09-14T22:03:17Z")
> [@](#): > > This indicates that the calorie count in a baked and raw potato are the same. The Calorie content might be the same, but that doesn’t mean that the Calories will actually be used by a human eating it. ---
**Author:** ![JoelUpchurch](https://avatars.discourse-cdn.com/v4/letter/j/f05b48/32.png) [@JoelUpchurch](https://boards.straightdope.com/u/JoelUpchurch)\ **Post date:** [September 14, 2011, 10:11pm UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/34 "2011-09-14T22:11:02Z")
> [@Chronos](#): > > The Calorie content might be the same, but that doesn’t mean that the Calories will actually be used by a human eating it. Yes it does. These are dietary calories if you bothered to look at the link. It isn’t like lettuce where most of the calories can’t be metabolized by humans. ---
**Author:** ![Blake](https://avatars.discourse-cdn.com/v4/letter/b/a9a28c/32.png) [@Blake](https://boards.straightdope.com/u/Blake)\ **Post date:** [September 15, 2011, 12:27am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/35 "2011-09-15T00:27:50Z")
> [@JoelUpchurch](#): > > Yes it does. These are dietary calories if you bothered to look at the link. No, they aren’t dietary calories, which should be be obvious because baked and raw potatoes have the same value. [Humans can’t digest potato starch](http://books.google.com.au/books?id=EePNniHaROoC&pg=PA104&lpg=PA104&dq=%22potato+starch%22+digestible&source=bl&ots=bBv-EhVd42&sig=flMTuc_QpY3_hKxKCLNnkpFB7Z8&hl=en&ei=vkVxTuTNIaXBiQf94d2gBg&sa=X&oi=book_result&ct=result&resnum=4&ved=0CC8Q6AEwAzgK#v=onepage&q=%22potato%20starch%22%20digestible&f=false). We can only digest warm, cooked potato because that denatures the starch. Even cooked potatoes that have been left to cool have much lower human available calories than the same potato had a few hours earlier. > [@](#): > > It isn’t like lettuce where most of the calories can’t be metabolized by humans. That is exactly what it is like, in fact moreso. It’s more akin to newspaper: full of calories and utterly useless to humans. ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [September 15, 2011, 12:49am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/36 "2011-09-15T00:49:34Z")
Read Richard Wrangham’s Catching Fire (there is a review at [Catching Fire: How Cooking Made Us Human by Richard Wrangham | Books | The Guardian](http://www.guardian.co.uk/books/2009/oct/17/catching-fire-richard-wrangham-review)) to see the difference between the nutritional value of raw and cooked food. Potatoes particularly are always mentioned as an example of a food, that when raw, has no available calories. And no taste either. ---
**Author:** ![JoelUpchurch](https://avatars.discourse-cdn.com/v4/letter/j/f05b48/32.png) [@JoelUpchurch](https://boards.straightdope.com/u/JoelUpchurch)\ **Post date:** [September 15, 2011, 12:59am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/37 "2011-09-15T00:59:59Z")
> [@davidm](#): > > How about high-rise farming? > > [http://www.verticalfarm.com/more](http://www.verticalfarm.com/more) I skimmed the article and thought it was somewhat fanciful. I live in Central Florida and we have a lot of greenhouses and know a lot about indoor farming. There is demand for vegetables and flowers out of season, but if that article was true it wouldn’t make much sense to use conventional outdoor farming. The limitations on feeding another 3 billion people isn’t land, but money and water. ---
**Author:** ![StuffLikeThatThere](https://avatars.discourse-cdn.com/v4/letter/s/bc8723/32.png) [@StuffLikeThatThere](https://boards.straightdope.com/u/StuffLikeThatThere)\ **Post date:** [September 15, 2011, 1:31am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/38 "2011-09-15T01:31:39Z")
> [@Darth\_Ayebaw](#): > > … that’s about 300x10 or 3000 eggs a year, in a 5x5 plot of land. I don’t think anyone has pointed out yet that your buddy is expecting nearly an egg a day per chicken. This is not going to happen year round unless he invests in the right kind of buildings and lights. We keep chickens, and they lay when the light cycle is right for them - roughly March through November. They don’t lay an egg a day toward the beginning or end of that, but through the summer they do. Commercial layer houses use light and heat to make the conditions summer-like throughout the year. They certainly get or exceed 300 eggs per year, but they have significant structures and overhead, and it’s a model that only works economically on a huge scale. If you keep chickens outside without heat/light intervention like we do, you can plan for about 200 eggs per year per chicken, if you know what you’re doing. (Full disclosure: When I say “we,” I mean “my husband.” He’s the one that knows what he’s doing.) Regarding a 5x5 plot for 10 chickens … I’d say that’s about the space our chickens have in their coop. _However_, they are let out during the day to go scratch up some lovely bugs and grubs and stuff, so they have a much greater walking-around area than that. And their coop is on wheels and gets moved when they’ve exhausted the grass underneath. (Google “chicken tractor” for examples.) They thoughtfully leave behind poop to replenish the soil. Hope some of that’s helpful. ---
**Author:** ![JoelUpchurch](https://avatars.discourse-cdn.com/v4/letter/j/f05b48/32.png) [@JoelUpchurch](https://boards.straightdope.com/u/JoelUpchurch)\ **Post date:** [September 15, 2011, 2:03am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/39 "2011-09-15T02:03:37Z")
> [@Hari\_Seldon](#): > > Read Richard Wrangham’s Catching Fire (there is a review at [Catching Fire: How Cooking Made Us Human by Richard Wrangham | Books | The Guardian](http://www.guardian.co.uk/books/2009/oct/17/catching-fire-richard-wrangham-review)) to see the difference between the nutritional value of raw and cooked food. Potatoes particularly are always mentioned as an example of a food, that when raw, has no available calories. And no taste either. I think you might want to go back and see what he said exactly and keep in kind that Dr. Wrangham is a primatologist and not a dietician. I did some checking and part of the starches in Potatos are Resistant Starches that are broken down by the bacteria in the lower intestine instead on the enzymes in the upper intestine. This creates short-chain fatty acids which are considered better for you than starches that break down into glucose in the upper intestine, since it doesn’t raise your blood glucose. [http://lowcarbdiets.about.com/od/nutrition/a/resistantstarch.htm](http://lowcarbdiets.about.com/od/nutrition/a/resistantstarch.htm) If you couldn’t get calories from raw potatoes, then surely the raw potato diet book would be on be on the best seller list. ---
**Author:** ![groman](https://avatars.discourse-cdn.com/v4/letter/g/73ab20/32.png) [@groman](https://boards.straightdope.com/u/groman)\ **Post date:** [September 15, 2011, 2:30am UTC](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836/40 "2011-09-15T02:30:25Z")
> [@ZenBeam](#): > > All of these scenarios, though, have to ignore the land required to grow the food the animals eat. Not really, no. The trick is that not all animals are able to digest all foodstuffs equally. The scenario I am envisioning is that a chunk of land can easily grow something that has absolutely no caloric value to a human, and would require tons of energy in fertilization, tilling, weeding, planting and watering to grow anything directly edible to a human. However, what already does grow there on its own is a perfectly good food source for some animal. Why is it so hard to believe that the inefficiency of using a step that involves animals might be lower than the inefficiency of using horticulture? So far I have not seen a cite for anything that would indicate this can’t happen. It seems like it usually doesn’t happen though. I’m not the one making sweeping claims that it’s always impossible. [Previous page](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836.md?page=1) [Next page](https://boards.straightdope.com/t/most-efficient-use-of-land-for-growing-food/595836.md?page=3)