[Andy Carson]

I haven’t gotten ahold of enough farms to get a complete picture of all the ways that hogs are currently raised under tree cover, but I have learned some things. One method is to section off pre-existing forest into small paddocks and rotate groups of hogs through these at high stocking rates (30+ per acre). When the hogs are moved to a new paddock, so is a one ton feeder filled with hog ration, which is always kept full. It was hard to determine the percent of the diet that came from forage or mast in this system because of the omnipresence of supplemental feed. Also, determining how much more potential there might be for the woods to produce food is difficult because there isn’t always knowledge of the species or populations of trees in the paddocks (other than that some are oak). Again, I don’t know if this is the “standard” for this type of hog feeding, but am gaining a greater understanding of why the ecology of systems like this are brought into question. A planned system of feeding hogs primarily off of purpose planted and managed tree crops, at least in my mind, would be much different. The good news is that farmers and the public alike does seems to be interested in this idea. Also, there seems to be some room for improvement, which means I wouldn’t really be “reinventing the wheel.”

[Andy Carson]

I hear you, Carl, it’s a funny term. Maybe we should come up with a new one? “Agro-Grovery” “Agro-Orchardage” how about “Grovo-Piggery” 😀 I’m kidding of couse… Another thing you touched on is the tillage capability of the pig, and it sure would have been nice to have some “plows” that worked reguardless of weather this spring. I also think you are right about some field crops being needed for the pigs. The breeding sows would have to get through the winter on this, and some form of protein rich feed would lkely need grown as a supplement with the hogs. Still, though, it seems that the bulk of the energy could come from trees, and the amount of field crops could be a small fraction of what it is with corn/soybean factory system. Again, a good example of a small flexible system that is able to make use of a wide variety of natural “skills” of a particular animal. I googled up a phone number for Brown Boar farm and think I’ve give them a call and pick thier brain a bit. I will report back. You don’t happen to know, do you Carl, what kind of oaks these are or have a rough idea what kind of percentage of the trees in these wooded paddocks are oak? I saw a couple photos of some big trees on the brown boar website and am guessing these trees weren’t planted for the express purpose of raising hogs… It all factors into the feasability of the concept. Thanks for the contact info.

[Andy Carson]

I think this is a good idea especially if there is interest in it. Let’s say, just for argument, that I can streamline a system for raising hogs off of tree crops. Let’s further say that it could indeed produce 4-5 organic finished pigs per acre per year with no tillage and minimal maintainance. Would there be interest in such a system, given that it would take several years to get up to speed??? No sense working on a system that no one would implement, even if it reaches it’s goals… It sure makes alot of sense to me, but sometimes I am attracted to things no one else is.

[Andy Carson]

It is interesting that the ecology of this type of system is a concern. I agree that is is unlikely that these planted forests/orchards would be very similar to native forests. Ecology is such a subjective word to me in general, but that another topic entirely. Either way, I think it would be more fair to compare the ecological impact of this system to the more standard corn/soybean hog raising system rather than to native forest. In other words, is it more ecologically sound to raise hogs in planted trees at a low stocking density or is it more ecologically sound to use the ground as cropland and keep the hogs in confinement. Based on rough math, the carrying capacity of tree crops is at least the same, if not more, than the carrying capacity of cropland. Also entering into this would be the power required to till, plant, harvest, and store crops each and every year. This power could be produced from animals, of course, but feeding and housing these animals would require even more land and further reduce the efficiency of the cropland-confinement system.

PS. Personally, I have only ever raised pigs in confinement. I found it suprising that this system seems so possible. Maybe it shouldn’t be, as forests are where pigs came from, but it was to me. I am trying to recheck as much math as possible because I think J Russell Smith overstates his case a bit. He said in one part of the book that hogs could be stocked at 2 per mulberry tree, which would end up with 80 per acre. Maybe for a short time, but the math doesn’t support that this stocking rate is sustainable. Still, the system looks competative with corn for total calories per acre and produces a crop every year (unlike ground for corn, which is often cycled).

[Andy Carson]

@goodcompanion 27500 wrote:

But has anyone actually done this with walnuts, fed them to pigs in great quantity? Walnuts are toxic. Every part of the tree, leaf, wood, nut, has this allochemical to which some people are violently allergic but even “normal” people will develop symptoms when overexposed to it–for me walnuts make parts of my mouth numb if I have more than a few. What about pigs?

I would be curious if anyone has used walnuts too. I would be most curious about english walnuts, as I want to eat some too and the black walnuts are (as you say) messy and tough. As far as hogs being fattened on nuts in general, the idea has been around a long time. Jamon Iberico is from pigs fattened on acorns. Prosciutto di Parma is from pigs fattened on chestnuts and whey.

[Andy Carson]

Hi Jerry,
Let me recommend Gene Logsdon’s book “Small-Scale Grain Raising.” It’s a very informative book that lays out many options. The devil is in the details, but this book will introduce you to options and might help you set some goals. As far as planting times, your climate is so different from mine, I’m not going to be of much use. All I can say is that if you watch your neighbors, and talk to them, you can get a good idea of the kinds of crops you can grow easily and when to plant. Welcome and good luck!

[Andy Carson]

By the seasonality of the tree crops, I was refering to a mix of both nut and fruit crops. Specifically a mix of mulberry and walnut trees. The mulberry produces over a long period in the summer from June into August. Sweet, soft, small fruits seem like they would be perfectly picked up by hungry little mouths born in March. March, incedently, is the most common birth month in european wild boars. There wouldn’t be alot of fruit right way, but the piglets would be small and might still be with the sow. Because the sow doesn’t need bred back right away, high protein milk would be avaliable for a longer time and could help get them started. Mulberrys produce fruit until about August. In August, the walnuts start falling, producing massive amounts of food when there are big enough mouths to eat it. After a month or two of eating walnuts, it’s mid october, which is a good time for slaughter. I think what we have here is an animal perfectly designed by nature to eat tree fruits and nuts, especially if the farrowing time is right. That’s what I meant by the seasonality matching quite well.

[Andy Carson]

Some interesting math…

The yield of mulberries from references seems to be quite variable with an average of 9 tons per acre. Seems impressive, but it’s wet food. The calorie content is 43 Kcal per 100 grams, which comes out to be 3520 megacalories per acre. 2136 lbs of corn would yield the same number of calories. The mulberries have 1.44% protein, which doesn’t seem impressive until you take into account the amount of feed that is consumed to satisfy caloric needs. It would come out to the equivalent of corn with 12% protein. Figuring about 1000 lbs of corn to raise a hog, the stocking rate would likely be something like 2 hogs per acre.

The yield of walnuts from commercial farms is easier to find, they target 5 tons per acre. Quite impressive, but about half is shell and commercial farms would likely push harder than small organic people would, so I’ll figure 2 tons walnuts per acre is a reasonable goal. The calorie content of walnuts is 654 Kcal per 100 grams, which comes out to be 11890 megacalories per acre. It would take 7220 lbs of corn would yield the same number of calories (IE 130 bushel per acre corn!!!). Walnuts also have 15% protein, but are more concentrated than corn, and comes out to the equivalent of corn with 8% protein. Figuring about 1000 lbs of corn feed to raise a hog, the stocking rate would likely be something like 7 hogs per acre.

The advantage of mulberries (as J Russel Smith puts it) is that they yield over a longer period of time. Either source of feed would require a little (and just a little) extra protein that could be foraged for or fed from other small fields, such as a field of clover that was rotationally grazed. The seasonality of when these tree crops become avaliable and when spring born hogs need these foods matches quite well, but should we be suprized? Not really, as pigs likely evolved to subsist on food from trees with some extra foraging to supplement. Obviously, this stocking rate is rather low, which is one disadvantage. Or is it? The low stocking rate and the presence of “real” food couples with rotational grazing would likley be much less desctructive to the trees. Another disadvantage is that as the tree crops are seasonal, it is hard to image how hogs could be raised throughout the year. Likely there would be one “batch” per year, which is fine with me.

[Andy Carson]

I am actually concidering harvesting the grain. It would get my feet wet harvesting a small grain, and that would be a useful thing to have experience doing. It opens up lots of possibilities from a crop selection standpoint. I would probably end up mixing it into animal feed in smaller percentages. It might help… I am only going to get serious about that if I can’t find anyone who wants to trade the standing rye for something (like some field work). No takers so far. I actually looked into the whiskey mostly out of curiousity. The regulatory issues of making and selling spirits seem like something I don’t want to get into, however, and the capitol investment is not small. I shouldn’t drink that much whiskey either, or I really ever get any farming done! 😀

[Andy Carson]

@goodcompanion 27309 wrote:

There is something to do.
It won’t solve everything.
It can restore some measure of balance.
But maybe not for everyone.

I guess I can live with that.

I just wanted to say what a profound and poetic set of statements this is. Having the freedom to live as you want and be able to shepherd your land by your own ideals is so incrediably appealing. It’s hard to imagine how one would achieve this level of satisfaction long term if working to achieve someone elses vision. Just like Erik indicated, once the “help” is trained, they are likely to leave and start thier own farm. Good thing too, if you ask me. So, we come back to that amount of land a family can opperate without much outside help. With animal power, it’s hard to imagine how that amount of land could possibly be 5000 acres.

[Andy Carson]

Thanks for the thoughts and encouragement everyone. I have to say that as mad as the rye has made me, it is amazing at weed control. Absolutely zero weeds where the rye is. Granted, no planned crops either, but I’m really impressed with the rye in this way. I really wasn’t expecting this as the fall growth was not impressive. I really wish rye itself was more useful because it’s sure easy to grow. I have read that rye can be fed to chickens and pigs, but only if mixed in at 25-50% of the total feed ration. Other than that, I have no use for it directly. The corn seed I bought seed for is bloody butcher, which I have seen listed as 100-120 days depending on the seed source. Good idea about the shorter season corn though. I’ll have to check this out. I hope I can get some use out of my bloody butcher seed next year, it wasn’t cheap. One of the “lessons” I learned last year was to make sure to buy your seed early. Maybe that’s not always the best way to go, as I may have to buy seed twice…

[Andy Carson]

A look at another source might be a good answer as to why this system is not used more commonly… Apparently, the conversion of biogas into electricity is only 20% efficient (WOW!) and it takes about 35% of the total methane produced to keep the reactor warm. Probably not as good of a system as I had previously thought, but it still seems to have potential. The authors quote a cost of $90,000 for a lagoon, so it would likely be most useful if one could find a way to use the biogas directly instead of loosing 80% to electrical conversion. Interesting read…

http://www.attra.org/attra-pub/anaerobic.html

[Andy Carson]

Another possibility is the use of methane from anaerobic digesters. They are usually used for cattle manure, although I suppose they could be used for other manure as well. If a cow (or steer) produces 60 lb of manure per day, a good digester will produce 60 cubic feet of methane from this which will yield 36000 BTUs per cow per day (60*600 BTU/cubic foot) (from http://www.habmigern2003.info/biogas/methane-digester.html). 36000 BTUs is equal to about 10 KWH if the conversion to electrical power was 100% efficient. Of course is wouldn’t be, and would probably have a loss of 50% or more, yielding maybe 5 KWH per cow per day. That said, some household appliances could be run off of the gas itself (which is similar to natural gas) and not incure the loss from conversion to electrical power. Even if it all the methane was used to make electrical power and a 50% loss was incured in the process, that would make 1825 KWH per cow per year (5 KWHx365days). At $0.15 a KWH, this would yield a savings of $273 per cow per year, so 4 cattle might pay your electrical bill if you watched your consumption closely… It’s still alot of investment in the digester and generator, but thought I would throw this idea out there as well.

This analysis doesn’t include (of course) the “fringe benefits” of money from the sale of milk or meat from cattle. It also doesn’t include the monetary value of the work oxen could do.

I personally find it fascinating that the power excreted out the rear of an animal seems to be close to (and maybe greater than) the amount of power they are able to produce with thier muscles. In this scenario, they essentially become roaming collectors of the solar power that is captured by the plants thoughout the farm. This essentially turns the entire farm into a solar panel. Although this biological system is surely less efficient at producing electrical power than a solar panel (with energy passing through various forms and losses are incured at each step) the mammoth size of the “panel” and it’s relative cheapness, would likely make the system competative. Not to mention the fringe benefits…

[Andy Carson]

Steven,
I can see how you would think this, but forecarts are just so stable it is hard to imagine how one would fall off one in normal farm use. I have only fallen off mine once, because I was trotting on an old logging road and one wheel hit a foot tall stump hidden in grass. This was a major launch, but in my experience it takes something like this to knock someone off a forecart (unless they’re not paying attention). In comparison, I also have a ride-on-top disc that I have fallen off of several times at a walk due to rough terraign or rocks. I have never been injured on this disc, but I would say the risk of me falling in front of the blades is higher that the risk of me falling off a forecart at all…

[Andy Carson]

Great tip Dave, I bet that works really well. I will have to be careful about the placement of the chain b/c I use notched discs, but I think I have room for them without a big risk of catching. Thanks!

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