Human energy spent versus kilocalories harvested.....

I can't seem to find tabular information on the following:  Is there a comparison of different plant foods presented as kilocalories expended through manual labor versus kilocalories of food item obtained?  Did Mollison make such a comparison in his book?  Preferably this analysis might weigh the fact that tree fruits are often readily picked and consumed, but are available typically in brief production bursts once per year, whereas roots and tubers (a bit harder to obtain, energy-wise) might on average need more cooking/processing, but be available (and storable) during longer periods of the year.  Per kcal obtained, for instance, it seems like maize grain is much easier in kcal of human labor to obtain than wheat.  I could find bits and pieces in scattered writings, but was thinking someone must have put together a table or analysis of this kind, yes?  Apologies if it's right in front of my nose and thanks for any links or reference.

What a great topic!

I'm thinking Sweet Potatoes are going to come out high, because they produce a lot of calories per land area and don't require processing to eat them - just dig them up and cook. But it will be hard to eat enough per day  to provide sufficient calories in the diet. Apples produce even more calories per land area and can be eaten raw, but require unrealistic amounts of consumption in order to provide sufficient calories.  Tree nuts look like a strong contender.

http://www.fao.org/docrep/t0207e/T0207E04.htm

http://www.gardeningplaces.com/articles/global-food-crisis.htm

shoot, I thought I had something, but the information didn't distinguish between human and mechanical labor, merely "labor hours"

I would expect regular potatoes to be very high on that list too.  If you grow them in deep mulch you don't have to hill, weed, anything.  Just plant them and dig them up.

Hmmm....it would seem like something that might be informed by past surveys on common foraging or forage/farming societies.  There would be anomalies to separate out, of course, but I think many of those types of populations would incorporate into a yearly cycle where to get the most calories for the least amount of effort, as long as other nutritives are not sacrificed in too great an amount. Thanks for the interest, Tyler, I'm going to keep plugging along and will post updates as I find them.  And Todd, up here in the north, that's what I was thinking as well....our potato crop is pretty important to us in terms of food security (and ease of harvest) even though mechanically-harvested wheat and maize is king around here.  It would be nice to envision one's property in terms of a balance between all of these potentials for each person's subzone:  root/tuber crop, tree crop, seed/bean/grain crop and seeing how, say, the season on fresh eaten vegetables/leafy greens can be extended and overlap with stored/dried root-tuber-apple-fruit supplies, all with a localized vision of one's energy availability for manual harvest.  It just seems like there is still much adapting of different fruits and vegetables that might be done towards these goals.

John Weiland wrote:Hmmm....it would seem like something that might be informed by past surveys on common foraging or forage/farming societies.  

Now I'm confused.  I thought you were wondering about which crops were the most efficient in terms of calories needed to produce them by human labor, that is agriculture/horticulture/farming, not foraging.  Are we talking about farming, or are we talking about foraging?  Or both?


Here's an article comparing labor requirements of early farming versus foraging:  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3064343/

@Tyler L:  "Are we talking about farming, or are we talking about foraging?  Or both?"

I'm thinking along the lines of something a forager might find caloric, nutritive, and easy to harvest, but that *might* also be easy to plant in one's own domain.  You are right....there may be some things that are easy to harvest as a forager, but difficult to grow in a farming-type situation....and the difficulty may incur high calorie expenditure to get the thing to grow right.  So I'm thinking of those foraged plants that would also be easy (as a perennial or annual) to adapt to one's growing situation.  As Todd mentioned, up here potatoes are pretty easy, both for planting and harvest (and all things in-between, assuming potato beetles and blight don't visit in the night).  There are old staples as well that have stood up over time....beets and other roots among the immigrant population and other roots and tubers used by the natives of the region.  We have sunchokes in the garden....first year we didn't even dig them, now they are "on the move".  We are unfamiliar not only with how best to use them, but with how much energy is involved to obtain the calories and nutrients they harbor.  So these would be starting points and then newly-adapted items that weren't previously grown (or at least *known* to be grown), again...with an eye toward calories in for calories returned, could be added to the mix.  With information exchange within a forum like this, some things might be put on a lower priority list if they would initially be considered to be too labor-intensive to try.  Doesn't mean it couldn't be revisited down the road.

Edit....also forgot to add that in addition to calories involved in harvest would be the calories involved in processing the foodstuff to an edible state.

I think so much is going to depend on one's locale.  In some parts of the tropics, it might take next to no effort to grow all the calories one needs, in a nearly complete plant-based diet.  In a cold, dry climate, it might be extremely difficult.   Crops that will easily produce a lot of calories in one locale might not grow well, or even at all, in another.  Looking to previous inhabitants might not be entirely helpful, either.  For instance in my region one of the staple calorie plants foraged was Sotol, a not especially tasty plant with an edible stem that has to be cooked for many hours.  I have it growing in my yard, but I hope never to have to survive on it!  It also takes several years to reach a practical edible size, which is fine if you're foraging, but not so great if you're farming.  There were other tuber and bulb things that were foraged here but a lot of them are nearly extirpated because of ranching over the past century.  I'm trying to research some of these to see if they might be appropriate for domestication.  One which I have success with is the native Canada Onion, which is one of our main onions.  It grows easily in the garden and is tasty.  It goes dormant and completely disappears during the Summer.  But onions can't make up many calories in the diet.

For information about the relative space needed and number of calories per unit of produce of various crops, I recommend How to Grow More Vegetables by John Jeavons.  There's some information here:  http://www.growbiointensive.org/grow_main.html

Seconding the importance of locale; depth and quality of topsoil, area of land available, wind, moisture, temperature variations. Don't know what the climate of N.Dakota is like, but if its anything like Lincolnshire I've thought about growing the following.

Apple Orchard might be good if you were willing to wait 5 years +, with the added benefit that you would eventually have wood to burn for heat. Plum can be quite productive sometimes. You could always turn the excess fruit into booze, feed the leftovers to poultry perhaps.

Chicory might be easy to grow, I've read its related to the dandelion.
Diakon. Burdock. Beetroot.
Squash and/or Pumpkins can be productive if the climate is warm enough.

Not the most high in calorie plants. Potatoes or sweet potatoes might be better, though there is virtually no top soil where I'm planning to grow and the soil is compact clay from decades of no rotation wheat farming. Perhaps Maize would be a good crop, but then I would suspect you'd have to add nitrogen fertilisers to the soil.

I would imagine that harvesting corn would be similar to walking in calories burned. In other words, harvesting corn for 30 minutes would be similar in calories burned to walking for 30 minutes, as they would use the same muscles, more or less.

I imagine that picking up the bags of corn and carrying them any distance would burn the same numbers of calories as lifting a weight and holding it.  

Carol Deppe discusses this somewhere, but I don't remember if there are numbers or just a logical discussion.  Potatoes, corn, squash, beans made the list; things like lettuce don't when based solely on calories.  

Beans or Peas are probably good, with the major benefit as legumes they are fixing Nitrogen in the soil. Broad/Fava beans  can be grown over the winter as well. Corn unless its GMO to my knowledge does not fix nitrogen to the soil, if you lived near a reasonably clean creek maybe you could use the gunk from the bottom as a fertiliser for the corn. As opposed to depleting the soil or making/buying in fertiliser.

Genetics of the person are pretty important as well, Scandinavians or Northern Europeans in general, are more adapted to getting more nutrition from dairy as opposed to people further south. Native Americans from what I have heard are less susceptible to Lung cancer from tobacco. Perhaps making beer from wheat, would provide more energy than making bread. There is a lot of talk about gluten from grains on the Internet, perhaps there is a way to break it down into something easier to digest. Though I have heard stomach acid breaks down gluten. Just a few thoughts.

@Richard Y: ".... if its anything like Lincolnshire I've thought about growing the following."

Richard, what is the status of your property right now, ....is it a new purchase where you are just starting out?  Lincolnshire appears to be a bit north of the 50th parallel, yes?....and I would think you could follow that parallel around the globe (as well as its equivalent in the southern hemisphere) in search of things that may grow in your region.  Naturally, one has to decide the extent to which they wish to bring non-domestics onto their property and there is the additional question of a country's policies regarding this as well.  But for starters (conceptually speaking), if you are looking to add some unusual items to your property, I would scan the ag pages of universities like those in British Columbia, Manitoba, and over towards Newfoundland/PEI.  Manitoba will have similar latitude, but much greater swings at the extremes of temperature.  Nevertheless, there may be some items from that region that would produce in your area.....what is importation of plant stock like between Canada and the UK?  

Practically speaking, I like to think of starting a venture like this the same way I envision natural succession working in an ecosystem.  In the photos below, we started out with straight, cultivated, plowed/chiseled, compacted heavy clay soil, even if the organic matter in the region is naturally higher than most.  After obtaining the property, we took the rented section back out of production and, with what we could afford, put much of it back into native prairie.  We encouraged some ecological succession in terms of prairie restoration, but then let natural laziness on our part be the cause of forest succession.  There can be seen below the usual elm/ash/box elder sapling unmanaged and wrangled mess on the left with the native prairie grass on the right. But the "food" succession was partially planned as well:  We knew that apple, cherry, and other trees would not be yielding for some time, but that small hardy fruit berries could begin to produce (even if not so abundantly) within 2-3 years from planting.  Since these smaller berry plants might be moved more easily than a larger tree, we knew we could be a bit lax in deciding where to place them and indeed we have had to move a  few of them as the property took shape.  Succession also took place in the fact that we started out with sheep, angora goats, and a llama, so that was the early source of manure where now we have chickens and (sanctuaried) pigs, as well as a few stray geese that were on the property when we moved in. So the point of all of this being that you can start with more immediately-yielding items while you are waiting for trees to mature.

You mentioned the poor, clay soil in your area, but would there be a ready source of manure in your region?  In your area, is all of the manure already "spoken for" in one way or another?  It's  amazing how quickly things can turn around with a small addition of this source of organic matter...and here once again you can prioritize and place legumes in poorer soils and have more needy plants in the soil you deliberately condition.  But as important, at least for us at this time, was to mix plant foods that we enjoy with those that do well and are easily produced and harvested in this region.  I'm not a huge fan of beets, but they grow really well here (~50% of all US sugarbeet is grown in Minnesota and North Dakota) and may be a good source of calories, so who's to argue with that?  But I like the idea of paw paw trees and although they don't naturally grow here, there is information from another thread that they may all the same with a bit of encouragement.....and adaptation.  And our apricot tree has exceeded expectations.  So a bit of what does well mixed with a bit of what one personally likes.

Tyler, yes...thanks for the Jeavons reference.  I looked at our copy on the shelf and see that I purchased that in the mid-1980s, so that must have been in Oregon where there was a stronger influence of that type of agriculture versus where we live today.  It was pretty inspirational in terms of how we have gone about gardening since then.

Beets grow really well for us, but we don't like them, and they don't have enough calories to count as a calorie crop.

Beets = 195 calories per pound, Potatoes = 347 calories per pound

Tyler Ludens wrote:Beets grow really well for us, but we don't like them, and they don't have enough calories to count as a calorie crop.

Beets = 195 calories per pound, Potatoes = 347 calories per pound

off to the side of calories and exertion....this is so ironic...those of us who love beets and can't get them to grow well, pay premium prices at the farmer's market...have you considered trading beets for produce that you love?  

@Tyler L: Re: "enough calories to count as a calorie crop"

I was looking up the term 'calorie crop' and was wondering if there had been some use of this term and criteria for some foods being considered such.  As I've come up empty handed so far in additional searches for good data on caloric plant foods, do you have a site where that term was used?  Or even if not, where the idea was being addressed in a list of such foods across different growing regions?  Thanks.

Edit:  Also to add to what you already noted -- "According to the FAO, sweet potatoes top the list, yielding 70,000 calories per hectare per day, nearly twice as much as wheat—and far more than that if you use one of several fast-maturing varieties. Jeavons also recommends potatoes, leeks, and parsnips for those looking to maximize calories per acre."  -- http://www.slate.com/articles/technology/future_tense/2012/06/food_security_what_crops_will_feed_the_world_if_we_run_out_of_farmland_.html

It addresses the maximization of calories per unit area, but not necessarily factoring in calories of human labor spent to obtain the plant calories.  At this point, parsnips are self-cycling in our garden...they do not die from the deep winter freeze and self-seed prolifically.

Calorie crops discussed here:  http://www.growbiointensive.org/grow_main.html

The only book I know of which is dedicated to the idea of growing a complete vegan diet at home is One Circle. The model diets are deficient in B12, iodine, and calories, and are really boring, but the book is a good place to start for trying to figure out a simple homegrown diet.  Crops are chosen by their "area efficiency" - they don't take much space to grow, and their "weight efficiency" - you don't have to eat too much of them to get sufficient calories.  Typically, grains are not area efficient but they are weight efficient.  Potatoes, on the other hand, are area efficient but not particularly weight efficient.  The crops studied for calories include Filberts, Garlic, Parsnips, Peanuts, Potatoes, Soybeans, Sunflowers Seed, Sweet Potatoes, and Wheat.

Thanks, Tyler....it took a bit of digging on that website, but I think this is the link to the summarized info:  http://www.growbiointensive.org/60%2030%2010%20Clar%20GM%202%2006%2011%2022%2006.pdf

Someday hopefully this will all be assembled into a table with additional crops for different locales.

My parents bought the piece of land for over 5 years ago next to where we live (the previous owner rented it to a local farmer and tried to get planning permission for housing), have some Silver Birch, Cooking Apples(Arthur Turner), Popular and Willow. Were end of season stock from a local tree nursery. The bottom 2 acres of land is trees with grass that is cut with a tractor, the other 3 acres is just grass with thistle, not many trees have some hawthorn growing there and wild rose.

To my knowledge importation of plant stock into the UK is pretty relaxed, but I could be wrong on that. The amount of land is not particularly a lot compared to local farmers. Been looking for seeds and roots on Ebay, would like to grow horseradish and raspberries, though the amount of roots I would like is quite expensive on Ebay for the area I would be looking at. Wholesalers might be the way to go, but I'm not after some of the larger quantities of commercial growers. I have some seed that I'm planting at the moment before it gets far too late in the season.

The district of Lincolnshire I live in known as south holland, tends to be one of the driest areas of the UK in Summer as a lot of rain via the gulf stream gets dumped on Wales. In the Winter or Spring though the ground can be quite sodden. The gulf stream keeps the temperature more consistent, so it doesn't get colder usually than about  -5c in winter,  a few years a go though it did get as low as -20c in Holbeach a local town.

A lot of people own horses near where I live, there is also barn kept cattle and turkey farming. Not sure on the regulations, for using factory farmed manure. I believe that silt dredged from rivers in the UK is classified as Industrial waste for some reason.

Sugarbeets were a major crop grown where I live (Sugar factory in Spalding) along with wheat, potatoes, cabbage, peas and rapeseed. Though sugar cane is more often used now due to regulations. Beetroot I think is mostly greenhouse grown. The wholesale prices sound pretty low £50 to £400 per tonne for potato main crop.

Sorry I couldn't link to the right page, but you found it.  Yes, it would be tremendously valuable to have information about calorie crops for different regions.  It's frustrating not being able to find basic information about some crops. For instance I'm trying to grow Queensland Arrowroot, a starch crop, but I haven't found information about how many calories it contains, so I don't know if it is a weight-efficient crop or not.

To me, the crops that return the most food value for the amount of labor expended seem to be beans, corn, and squash. They are big-seeded species that jump out of the ground and grow vigorously, so that they can out-compete the weeds. Nuts require a LOT of labor to harvest and thresh, but food energy is good. Fruit trees don't require much labor once established. Grains are pretty much a bust for any sort of small-scale hand harvesting.

Among annuals, the small-seeded species, or species that take a long time to germinate, or that grow slowly seem to require too much labor for weeding. That would be greens, herbs, spices, carrots,  etc.

If I would choose for myself, of what I like to eat, (i don't see food just as fuel, and some things I like more than other), I would say, as my first choice - when taking into account easily available calories in relation to work etc and storable as well, and the fact that there are really tasty: CHESTNUTS! If I had a piece of land, I would plant loads of these trees...
I would also go for lots of fruits trees:... APPLES are totally amazing: you can use them in so many ways: juice, cider, dried, in desserts, in salads, baked in the oven...  and there are so many varieties and tastes.
And also a bit of nut trees, pumpkin, sweet potatoes, maybe some beans. Squash is also a good option, but I'm not really sure how long/well they store.

It may not be worth my while, but strolling between some buildings near work, I decided to pick up some pears fallen from a tree.  It's a really old tree growing on the north side of a building.  I suspect its pollinating partner is the other tree about 50 ft away, quite a bit smaller and never very prolific in flower production...and to my recollection, never producing pears.  As the pears are small, never soften well to ripeness, and are from a taller tree, I suspect this was a hardy heirloom type that was planted some years ago, probably targeted for canning or storing.  So the pears that I picked up will be allowed to over-ripen a bit before getting planted in an area for overwintering the seed.  If anything arises, it can be tested down the road for self-fertility.  If the partner tree is still around at the time, maybe it can be used as a pollen source as well for additional testing.  I'm curious about a description made regarding the Bartlett pear in the following, and note to Richard Y---have you considered pears as well for your place?:   "Self-fruitful in California, but may need a pollinizer in cool and cold climates."  --  http://www.treesofantiquity.com/index.php?main_page=product_info&cPath=2&products_id=191   Although I was aware that self-incompatibility systems could be 'incomplete', I was not aware that location/climate could have such a strong influence on the trait.

@Keira O: Chestnuts....yeah, my wife dreams of having these, remembering how they were enjoyed in her youth in the eastern US.  And I agree about apples...a pretty diverse and amazing crop for northern climes.  Did you ever read the book called "Cider" by Annie Proulx?

Joseph, I agree about the (small) grains and would possibly just consider testing some of the hulless varieties of oat and barley if we felt them to be a priority  -- don't know if there are ancient wheats that are hulless.  But next to these, maize is pretty easy to get usable grain, either left on the cob or shelled immediately after drying.

A few more photos below from the past few days--1) apricots being enjoyed by the fruit flies as well as ourselves, 2) the grapevine that ate our screen porch, and 3) that weed-tree of the plains, the box-elder...which being related to maples yields a decent sap, even if a bit lower in sugar to sugar maples.