Composting Woodchips

Hello everyone,

Let me start by giving a shout-out to everyone who responds to my posts.  No matter how eccentric the idea, I always get sound input/advice/much needed knowledge about my intended project.  Thank you very much.

So this time I am looking for something to do with my wood chips.  As I have stated on other threads, at present I have an 8x4' trailer literally overflowing with wood chips I chipped up this fall.  The parent material was almost entirely autumn olive, an aggressive invasive in the reason.  I own about 9 acres, 3 of which is in a field or meadow that I need to keep mowed due to local covenants.  I can't mow the autumn olives because they grow way too fast and way too large for a mower.  Instead each fall I go to a local rental center and rent a 6" wood chipper that makes short work of the autumn olives.  This year I had a bumper crop of wood chips and left them in a trailer to age a little bit.  At first, the pile does heat up as the autumn olives have a fair amount of greenery and moisture when they get chipped.  Additionally, the autumn olive is a very soft wood.  A couple of weeks after the pile gets started, it gets hot enough to burn my hand if I were to leave it in the pile too long.  The problem Is that I have little to no way of turning the pile, and worse, some of the chips are quite large (2"x 4" approximately).

I added a picture of my chips.

At present, I am letting them age.  This does not mean rot down to earth, but rather hopefully the microbial action will soften them further and expedite their decomposition once on the ground.  However, I would like to see them break down further.  I am sure that by now, the wood has used up whatever green material was their in the first place.  So one thought has been simply to add more nitrogen.  the current options are:

1)  Use urine
2)  Use chicken droppings
3)  Use 10-10-10--I still have some of this laying around as I bought it before I started down a more "Permie" path.  I know this is note exactly a "Green" alternative, but I do need to do something with those bags, and applying them to a big pile of wood chips might actually be a fairly green method of disposal--and add nitrogen at the same time.
4)  Let them sit and apply as a mulch
5)  Any other ideas?

Any how, thanks in advance, and thanks for giving me the time to discuss these ideas. I have no doubt these discussions make me a better gardener and if I could help someone else with my ideas, that would be even more wonderful

Eric

For me the best use has been #4...mulch.  The soil under the mulch becomes gorgeous in just a few years.  Better yet, use as a mulch and inoculate with wine caps.  I mulch in the paths of my raised bed veg garden and I swear that the path has better soil than the beds now :)  Since noting that I started mulching the beds with wood chips too, which I pull back and add kitchen scraps under, then re-cover with the chips.  The worms then take care of the kitchen scraps very quickly for me making the raised bed soil great too.

Wood chips are a wonderful resource to us gardeners.

Mulch.

Next time you have fresh chips, you might add some mushroom spawn. If you make compost you could grow different kinds of edible mushrooms.

It sounds like a lot of work. If you don’t need mulch or compost, you might be able to rent or hire a brush hog to just grind it and leave it in the field. I would go with mulch though.

Another vote for mulch!
Use the largest pieces for paths or biochar.

OK, I will definitely use at least some of the woodchips for mulch. but I bet that even if I apply a nice layer, I still have extra woodchips.  How "permie" would it be to use up my 10-10-10 to help decompose those chips?  I have the bags, want to rid myself of them and don't really want to use the 10-10-10 directly on soil, niether do I want to throw the stuff away.  Would use of the excess 10-10-10 applied to woodchips be a valid means of remediating the stuff?  Further, I could add chicken droppings to kick-start the biology.

Ken,

Actually I do own a small subcompact tractor with a loader, bush hog and flail mower.  I usually mow in fall, but in that short time, the autumn olives get too big for my tractor (only 24 hp/18ptp hp, 4' mowers).  In fact, some seasons I have simply mowed around the Autumn Olives to give greater volume of woodchips the next year.  Unfortunately, now I have more chips than I know what to do with them, and while they WILL make a valuable mulch, I also thought I MIGHT be able to turn at least some of them into compost to help amend my terribly dense clay.  In this mode, I was thinking that adding a lot of nitrogen might speed that process along.

Again, another thanks to your responses.  Winter is my stir crazy time.  I want to be out in the garden but all I can do is concoct new ways to enhance my existing beds and having a bunch of you guys there to discuss/bounce ideas is greatly therapeutic.  I am sure I will concoct another scheme soon and thanks in advance for indulging my need to rant occasionally.

Thank you very much,

Eric

I think they would compost down faster if they were in contact with the soil.  Could you dump them in a pile on the ground and turn them with your tractor bucket every couple of weeks?  That should speed up the process quite a bit.  Chipping and composting them in the summer would probably also help speed things up (vs winter).  I'd add #1, #2 and #3 to them.  If you're worried about the permie-ness of using the 10-10-10, just sell it to someone else who would otherwise buy it from Home Depot.  Then it keeps an equivalent number of bags of fertilizer from needing to be manufactured.

Letting them sit in the trailer seems like it will help the wood of your trailer compost and stress out your tires with all the weight on them.

Mike,

The trailer is composed of treated lumber so I am not concerned about it rotting.  This whole idea began with me thinking about using my daughter's hamster bedding in a pit or trench system that would let worms get to it so I like your idea of soil contact.  As the bedding is probably not saturated with urine or hamster droppings, I probably need some additional "greens" to go with it, thus the chips rotted with #1, #2, and #3.  As far as soil contact, I might find a place in the garden to dump and compost.  At present, while I do not plan to use 10-10-10 on grass or ground, I do wonder about its applicability in high carbon compost heaps.

If you believe yourself to be in a position where you have too many woodchips on a long-term timeline, I would look into Jean Pain style composting. It's a style of composting specifically designed for chipped up trees & brush (in Jean Pain's context, the purpose is wildland fire defense).

I don't think you'll get many answers on #3 as the goal of this forum is to discuss "organic or better" as a way to shape conversations.

Really though, all of your ideas are good ones. If you add more nitrogen, you will turn the pile a bit more bacterial and decomposition will speed up. But it will also decompose all on it's own without additional nitrogen, the pile will turn more fungal and that process will break down the wood chips over time as well.

I had also had the thought that you're composting the trailer. Your trailer would last longer without the chips in it.

No one suggested adding grass clippings or old hay to increase the nitrogen content.

If you don't have a use for wood chips, could I make the suggestion that you blow the chips out of the chipper and onto the ground. Moving the chipper to the brush will serve to do the distribution.

A few thoughts:

1.  I'd get them out of that trailer.  You'd be surprised who quickly microbes and fungi will turn the plywood sides of your trailer into spongy softness.  If they are getting rained-on, there will be biologic activity thriving within that pile, and the fungi will not make any distinction between the chips and the sides (and I would imagine bed) of the trailer.

2.  Chips get moldy quickly and then can be quite toxic.  I try to move my wood chips within a week because breathing those mold spores is BAD NEWS.  If you are composting chips, you should do so passively and not turn the pile unless you are wearing a mask with a fine filter (not a cheap paper mask).  Please take my word for it --- I've got cast iron lungs, and yet breathing mold spores for an afternoon while moving chips messed me up for a couple of weeks.  I don't take chances now.  Black mold is nothing to mess with.

3.  I'd save that 10-10-10 for your tomatoes or citrus trees.  The chips will break down in good time.  Adding synthetic fertilizers will only deter/kill fungal growth.  Fungi will provide all the N your chips need to break down.

4.  Count me in with the crowd above that favors just putting them down as mulch.  That little trailer won't go too far, but it's better than nothing.  Feed the soil (carbon) and the soil will feed the plants.

5.  Or . . . just dump them in a pile, leave them alone, and they'll be an amazing soil amendment within 2 years.  Just keep the pile moderately moist.

it is not all that much just enough to cover some paths in your veggie beds and it is a fast job.

You have an 8' x4' trailer full of chips? For comparison we get that delivered here around about 3 times per year by the local tree surgeons. They view us as a convenient drop off when they are working in the area, and they know that we will take large amounts. Typically it sits where it is dropped for 6 months or so until it is time for us to use it.

We use it for mulch, mostly on paths but also on some beds, and around some of our fruit trees. If you are concerned that you can't use it all as mulch then you probably are not adding it thickly enough. In our first year using woodchips I placed them in a layer of about an inch on the soil. They did very little to prevent weed. They did little to retain soil moisture - a few dry days and the soil dried out. They did a bit to help muddy patches on paths. In following years we put them down much more thickly. Typically 6", which compacts down to about 4" after a bit of weather and foot traffic. We find this works wonderfully. The soil beneath stays moist for much longer in dry spells, weeds are stopped dead - and the few that try to start are easily pulled. Earthworms etc... break down the bottom layers and feed the soil beneath. Now that our paths are established we top dress them with a couple of inches of woodchips each year to maintain them.

The biggest mental shift for me was in accepting that I should mulch a smaller area, but to a much greater depth. That was when we got excellent results.

Be aware, woodchips can rob nitrogen temporarily (a year or so) as they break down. Especially if they are dug in, or the soil disturbed at all. Bear this in mind if mulching around vegetables.

Michael,

You are probably right that I could dump the whole load on my garden beds and just let the excess pile up.  However, I am impatient and my mind is swimming with ideas as to how to make these chips into something more soil-like sooner.  In another post I stated that being a teacher, I get plenty of papers at the end of a semester/year to use in my garden as weed barriers.  A three page test serves as a mighty nice weed barrier.  Water will seep right through, but sunlight barely penetrates and weeds don't stand a chance of getting through.  I only need a few wood chips to hold these tests in place.

This brings me to issue #2.  Given that I have access to essentially unlimited paper refuse, I don't want to just add paper sheets or piles and piles of paper clippings.  These would inevitably turn into a sort of paper mache' crust that would render the garden largely infertile (or at least very hard to grow through/manage.  I want to find a way to compost these fairly rapidly.  

This takes me to issue #3.  I do have a nice pile of wood chips from invasive autumn olives.  I can't find a reasonable way to get rid of these weedy shrubs so I decided If I couldn't beet them, I would use them.  Now I let these bushes grow each summer (sometimes 2) so I can harvest them as biomass.  I go down to my local rental store, rent a 6" chipper for a weekend and feed the shrubs to the chipper and collect the chips as best as possible (lots of extra chips just laying about on the ground).

This leads me to issue #4 which is my hard, dense clay.  While I know that clay soil does have some advantageous properties, mine has a habit of changing from a gooey, sticky mess in early spring (can't cultivate) to brick-hard clay in summer heat (almost impossible to grow through it).  In fact, I recently posted on another thread started by someone who apparently has clay soil as difficult to work as mine.

Ultimately, my goal is to get a BUNCH of carbon in the soil where it belongs.  I did my master's research partly on the history of energy, and this inevitably runs through studies on agriculture.  Among my findings was a nifty little side note to energy but a potentially tremendous boon to gardeners (and farmers).  A 1% increase in soil carbon (in just about any form) yields upwards of a 25% increase in soil fertility--especially in carbon--poor soils.  As I said earlier, I am a tad impatient and I want to find a way to get all that carbon into my soil as best as possible.  In my humble opinion, that means turning the carbonaceous material into soil ASAP.  This is the reason that I want to add a bunch of nitrogen to the chips ASAP, let bacteria do their thing, and incorporate the final product into the soil sooner rather than later.  I am thrilled at the thought of using chicken bedding--nitrogen rich and teaming with micro organisms all ready to do their part.

This is also the reason I am not opposed to using existing 10-10-10.  Though I know that 10-10-10 is not a green fertilizer, it is taking up space in my garage and this seems like an ideal way to get rid of it.  don't apply it to soil, apply it to carbon where the micro organisms can use it to do their part to turn it to soil.  While I know that the 10-10-10 is not exactly green, would it do any harm to the composting wood chips (and hamster bedding which I am getting a nice supply of thanks to my daughter, and paper clippings I have in virtually unlimited supply thanks to my line of work (teacher)?  Please note:  I am not going out of my way to get the 10-10-10, I am using what I already purchased prior to discovering this site and trying to go down a more permie path.

I do intend to use the soil contact and worm action to help get things going.  These are the types of information I glean from using this site and I thank all those who have offered it to me freely.  If this sounds like a rant, it was not intended as such.  I simply love having the exchange of ideas that I get on this site so thank you very much for both reading and contributing.

Eric

My vote is to put it on the ground also. As you find uses for decomposing chips  just push the pile over with the tractor and collect the bottom layer. Youll be happy with what you find. As you continue to push and scoop,  youll develop a nice fertile trail similar to what a chicken tractor does.


As far as the fertilizer,  i have no issues with using it up.

If you want bacterial dominated compost, the 10-10-10 would be minimally helpful.  But fungal dominated compost, particularly with wood chips, is far better.  It will take bacteria years to break those chips down to a fine black soil amendment.  Fungi will do it much quicker with much better results.  Understand that synthetic fertilizers are hell on fungi.  You'll actually be slowing the decomposition down.

Watch the Back to Eden garden film and you'll see just how many wood chips you can actually use. I watched a couple on YouTube that brought 512 dump truck loads into their 2 acre property. Their soil was amazing.

Todd Parr wrote:Watch the Back to Eden garden film and you'll see just how many wood chips you can actually use. I watched a couple on YouTube that brought 512 dump truck loads into their 2 acre property. Their soil was amazing.

I've used approximately 75 loads on my 1/3rd acre suburban property in the past 12 years -- and considering that we've got a pool, a big 3-car garage and driveway, and a lot of concrete around the pool, we really don't have that much additional space (perhaps 50% of the lot) on which to cultivate trees and crops.  We get them by the truck load a couple of times a year and we always wish we had more.  Once you've got fungal dominated soil, the chips break down so quickly, it's amazing.  An 8 inch layer of chips only lasts about 6 to 9 months before it needs to be renewed.

Marco,

Can you explain to me why the 10-10-10 would not help the bacteria?  I understand why it would not help the fungi, but I am presently under the impression that nitrogen sources such as urine, grass clippings, comfrey, Coffee grounds etc. would provide an excellent source of N2 for decomposition.  Why wouldn't 10-10-10 do the same?  I don't want to apply my 10-10-10 to the ground directly as that would disrupt soil fungi networks, but my main goal is to get wood to break down ans as I understand, bacteria would do this the fastest and would gladly use the synthetic nitrogen to do this.  Where am I wrong?

Eric

Eric Hanson wrote:Mike,

The trailer is composed of treated lumber so I am not concerned about it rotting.  

Even if the wood is some of the newer 'treated' lumber I would be concerned about the opposite...the 'treatment' leaching into the chips/compost.
At the minimum, even a borate 'treatment' of the lumber could interfere with the composting process.

As I said earlier, I am a tad impatient and I want to find a way to get all that carbon into my soil as best as possible.  In my humble opinion, that means turning the carbonaceous material into soil ASAP.  

In my own circumstances I would take the opposite approach. I would look for a slower approach that took less total effort. The effort you are proposing includes:

Composting - potentially adding extra material to accelerate it, needing extra turning and mixing
Spreading in situ
Digging in situ to mix it with the clay.

This would undoubtedly lead to beds that were in peak condition faster, but that is a lot more effort than I would like to put into it. For the same amount of work total I would

Spread wood chips over an area three times the size
Wait patiently for the extra organic material to do it's magic.

You can even plant before the soil is "ready" - you might get marginally reduced yields, but the soil will keep on improving with no further effort on your part.

Marco (or anyone),

Please correct me if I am wrong here, but I was under the impression that bacterial decomposition is relatively fast and good for veggies while fungal decomposition is slow and better for tree & perennial crops.  Since I am adding this to my veggie garden I thought that fast and bacterial would be the way to go.  Also, would chicken litter and urine also cause the same problems as 10-10-10 regarding the sudden influx of nitrogen or am I missing something.

Just so you know, the trailer is in desperate need of repair so I am not all that concerned about any detrimental effects the wood chips might have on the sides.  I really need to rebuild it anyway and when I do, I am planning on using paint-on truck bed liner as a form of real protection.  Bottom line there:  I am not really concerned about the trailer.

Final question.  Do you have any "green" way to dispose of approximately 80 pounds of 10-10-10?  I originally purchased this when I was trying straw bale gardening.  I added quite a bit of the 10-10-10 to the straw and sure enough, it did heat up and a lot of the straw broke right down into some nice, crumbly looking material.  I was thinking that the wood chips would do a nice stand-in for the straw and happily eat up my excess fertilizer.  From your perspective, are the straw bales and wood chips good analogs for each other or again, is there something else I am missing.  I really do want to make my garden as green as possible, and this is the reason that I planted comfrey for the first time last year--a fertilizer plant.  Sadly though, the comfrey will not be available until well into the spring and I want to get the composting started much earlier than that.  And finally, though I stated it before, I want to get rid of the 10-10-10, but I don't want to throw it away, and spreading on wood chips seemed like the "greenest" option.

Given your home description, we are quite opposite each other.  You have about 1/6 acre of green space, and I have about 9 acres of green space.  between my 450' driveway, house&yard, I would say I have 8 natural acres, 3 wooded and 5 grassy.  Another thought for the 10-10-10 is simply to throw it on the grassy/meadow area, but somehow that does not seem as green as applying it to the wood chips.

As always, thanks for taking the time to read and give thoughtful perspective.  As I have stated before, winter time is my stir crazy time and bouncing ideas off another gardening enthusiast is a great way for me to expend my garden needs and come up with a few new ideas of my own.

Thanks much

Eric

I think the greenest solution for the the fertilizer is to sell it to someone else who doesn't have any qualms about using it and would be buying it in the spring anyway.  They would then use it instead of 80 lbs of additional fertilizer being made from fossil fuels.  

Mulch mulch mulch all day long..mulch mulch mulch while I sing this song...

The most efficient use of the chips is as mulch on the spot they fell, the next best thing would be around your garden. If you don't mind hearing about how this is what JC would do, Back to Eden Gardening is a very informative film about utilizing woodchip as  mulch after using it as chicken litter. You could also replace 99% of his religious references to the big G or JC with scientific terms and be accurate.

https://www.backtoedenfilm.com/watchfreeorganicgardeningmovie.html

Basically, you are creating a habitat between the top of the chips and your topsoil that supports a great deal more biomass and diversity due to microclimates and the absorption of water by the chips and stabilized humidity and temperature. Paul in the film goes up to 18" deep, but starts at 4-6" the first year. The fact the chips have gone through his chicken run is not emphasized enough as a key to his success, in my opinion.

Mike is spot on about giving it away and I'd suggest it go to non-food products. Ideally a wood lot. Not necessarily due to direct contamination of the food but rather how the concentrated nitrates and phosphates will kill a large part of your soil ecosystem that produces the best flavors and antioxidants etc. A wooded areas is most resilient to this as it can absorb a great deal and then reintroduce biodiversity that will be lost due to the concentrated chemicals with organisms from the surrounding area.
If you don't mind considering your land as your toxic waste disposal site (and I respect the idea of rejecting "not in my backyard") you could just dump the 10-10-10 on wood chips, preferably in a wooded area. Similarly you could theoretically dump diesel on soil and grow stuff tolerant to heavy metals and simplified soil biology very quickly (gmo corn) for a couple years until the soil collapsed ecologically and then physically . Then you get the benefits of petrochemicals just like big ag farming! Fossil fuels are really just decomposed ancient animals and plants, right? Your 10-10-10 is probably largely concentrated urea, phosphoric acid etc, right? I hope you get that I am being a bit tongue and cheek but also appreciate not wanting to just dump something you bought on someone else. I'd look at Bill Mollison's suggestions in the Permaculture Designers Manual for using those products, as he was not religiously against it in particular cases. I might call nurseries that use the stuff and ask if they would trade you plants for it.

The chips will also break down into soil quite quickly when spread out on the surface given all the oxygen available, but will do so with less loss of N and C to the atmosphere than in a hot pile. Also, any leaching from rain goes into your garden soil instead of under your pile. The key is getting the chips inoculated with compost teas, bokashi or ideally as bird bedding/litter.

Ben,

Fortunately, I will get a nice boost of N from my neighbor's chicken coop in a few weeks.  They use a deep litter method where (apparently) the decomposition of the straw and droppings generates enough heat to get them through the coldest parts of the winter.  Luckily, I get to grab a 4' bucket to add to my chip pile.  I figured that this is a double bonus as I get a bunch of nitrogen and a bunch of micro organism to get the compost party started.

So as of now, my plan is to empty the chips into a big pile on one of my beds, add chicken droppings, stir and wait.  I will likely turn a few times before I plant.  With a little luck, I will have some partially composted mulch to add on top of my garden.

Regarding the 10-10-10.  I don't want to sound like a broken record, but here is my main issue and reason for coming back to this over and over.  Right now I wish I had never bought the fertilizer in the first place and I sorta want to make reparations for acquiring it.  Giving it to someone else just means that I have "passed the trash."  I would love to find a way of undoing what I had already done and my thought was that adding it to the mulch would be the best way to use it up in a greenish way.  Since it did work in straw bales, I figured it would work on wood chips.  To me, this seems like the "least damage done" option as I will mainly be turning the wood chips and fertilizer back into compost anyway.  From what I can glean from reading these responses is that I will have a bacterial as opposed to fungal dominated compost.  Is there any damage beyond the relative lack of fungi (and I was not really planning on the fungi in the first place)?  As I bought the problem, I feel obligated to own the solution as well.  Keeping it forever is not an option so that means some sort of use for it.  Thanks for putting up with my obsessiveness.

Eric

Sorry if I'm also a broken record on this but I think you should sell the fertilizer or give it away to someone who would be buying it from a store anyway. We'll call them Chuck and they're at a 0 or 1 on the Wheaton Eco Scale.

Option A:
Use it on your property in a "greenish" way.  
Worry about bacterial vs fungal compost.
Chuck will go to Home Depot and buy 80 lbs of fertilizer.  

Final result is that for this upcoming growing season, 80 more lbs of fertilizer will be manufactured for Chuck.

Option B:
Sell it to Chuck.
Your property stays clean.
Chuck gets a deal
Explain why you're selling it and maybe he moves up the Eco scale a bit.

Final result is that for this upcoming growing season, 0 more lbs of fertilizer will be manufactured for Chuck.

Option C:
Something else even better?

You seem to be super concerned about the fertilizer.  I would just use it in the garden and be done with it. I would put it down, mulch with wood chips, and call it good.

http://www.gardenmyths.com/salts-dont-kill-plants-or-microbes/


http://www.gardenmyths.com/does-fertilizer-kill-soil-bacteria/

Pee! It's high in "N".  If you really loved your soil you'd pee on it.  *kidding* but wouldn't a 10-1-3 fertilizer be about right for woodchips?  

Eric,

Unlike annuals and leafy-greens, wood is comprised of different "stuff" that responds differently to bacteria than, for example, veggie scraps in a compost pile.

Wood cells are comprised of about 40 to 50% cellulose, 15 to 25 % hemicellulose, and impregnated with lignin (15 - 30%).  This depends upon the species of tree: the harder the wood (deciduous trees), the more lignin.  I'm not familiar with Autumn Olive, but I would assume because it's a fast growing invasive, the wood would be on the softer end of the spectrum.  Assume 15 - 20% lignin, which gives those cell walls their rigidity and strength.

It's the lignin that impedes bacterial decomposition.  To quote a nerd article:

"Only specialized biota, predominantly fungi, are able to synthesize extracellular enzymes that break down these structures into biologically usable forms (2). As a result, lignin turnover is distinctly different from that of the other major cell-wall constituents (cellulose and hemicelluloses) (3), and lignin is known to limit microbial enzyme accessibility to these more labile cell-wall polysaccharides (4). As such, lignin plays a key role in both terrestrial (5) and oceanic carbon cycles (6, 7)."

http://www.pnas.org/content/107/10/4618.full

Bacterial decomposition is great for leafy plants low in lignin and high in sugars, starches and nitrogen, and as such, throwing a handful of a high nitrogen fertilizer gives your compost pile a boost if the C to N ratio is out of whack (too much C).  But, as I stated earlier, fungi does not like synthetic fertilizers, and thus, throwing a bag of 10-10-10 will impede the longterm growth of fungal networks and ultimately slow your decomposition.  If there was a lot of green leafy matter in the original branches you chipped, that stuff (leaves and green material) will break down quickly, but the heart-wood of the branches will not.  So after an initial boost of heat from the nitrogen inoculation, once those leaves are all gone, you'll have chips that are resistant to fungal activity.

What would I do with 80 lbs. of 10-10-10?  I'd use in on my tomatoes and tomatillios, and I'd give my citrus trees a light feeding.  But 80 lbs. would last me for a couple of years.  If you've got a lawn, you can fertilize that, and then use the biomass to build a big compost pile, thus putting the N into a form that is compostable and easy to sink into the carbon in your compost or chip pile.  Did that make sense?  Use the synthetic N to grow grass, and then use that grass in your chip pile --- natural N that will not inhibit fungal growth.

Best of luck.

I hope I wasn't confusing on the 10-10-10...Dilution is the solution to pollution.

I think its hard to beat a disposal method of using it at low concentration (1/4 of prescribed amount) on a large amount of wood chips on a wood lot, ornamental or at least something other than your most prized edibles (blueberries, tomatoes, etc, i.e. things that taste much better from healthy, diverse soil).

Hello Eric,

   The growing season of 2017 saw me taking advantage of the local community gardening plots and the municipal woodchip pile.

The community garden has a stubborn policy of not allowing mulch materials, or any organic matter, to be left on the soil surface. They really like to till, it's a more elderly group, and they value their independence and diversity of techniques. Enough of my sarcasm though.

So at the end of the growing season I had about a cubic meter pile of woodchips just hanging out. I thought to myself, "here's your chance to try some thermophilic composting Kamaar". I added whatever green stuff was growing around my house, that I had chopped from my plot, a lot of comfrey, and some sunflower meal that I had leftover from my first season of growing (2016). Ended up being half woodchips and half green-esque material.

My experience is that the pile indeed got hot. For about 3-4 days. I'd then add more greens and it would heat up for another 2-3 days. I continued this for a month and in the end woodchips looked much the same. What had broken down was the fava bean stalks, tomato stalks, comfrey etc etc.

The pile of woodchips I mulched with for 2017 was twice the size of the pile I attempted to compost. The woodchips broke down more in the garden as a mulch than in my compost pile. If I had used manures that might have been different. If I had more greens it might have been different.

My plan for this upcoming year is to use that "failed" compost pile as mulch (and import many tons more woodchips), and see if I can inoculate the woodchips with King Stropharia mushroom spawn. My anecdata is that woodchips break down faster as a mulch than in a compost pile.

If you find a way to break those chips down in a hot compost pile, please share. It's the least expensive and most readily available source of carbon for me; and I for one would be most interested in, more-successful-than-mine, attempts at composting chips.

I have seen people produce biochar from wood chips.

If you're feeling industrious you can also heat water and cook whilst producing biochar.

Have a look at YouTube for some ideas:

https://www.youtube.com/results?search_query=biochar+wood+chips

(Note: making "char"/"charcoal"/"biochar" doesn't create compost or nutrition for plants (it destroys it actually), so whether it has other advantages or not I can't recommend using any sort of thermal decomposition, other than maybe something like a high-pressure steam-autoclave which probably isn't practical. )  On the other hand chemical processing could speed things along if you pre-soak the woodchips in water with dissolved woodash, potash, soda ash, or lime (limewater).  (Look up processing corn in limewater to make tortillas, or look up industrial methods of "cellulosic biofuel" processing.)

Generally, in the early stages woodchips will only be decomposed by fungi, not bacteria.  A list of optimal conditions for fungi will sound like a recipe for making bread, since yeast is also a fungi.  Warm temperatures (70-90°F).  Fungi need lots of water to grow.  Make it like a tropical rainforest, and dark.  It will also help to inoculate the chip pile with fungi, even just by mixing organic soil in with the chips.  Growing mushrooms probably makes sense if you know how to do that.

Most of that is easy but I suppose the main challenge is how to get an optimal temperature, neither too hot nor too cold, since the outdoor temperature for anyone asking this question is probably less than optimal, and the early stages of breaking-down wood won't generate heat.  However your compost pile *will*.  It might make sense to use a more developed compost pile as a heat source that is older and/or with less woody-material (of predominately bacteria so it generates heat) and then pile woodchips over top.  Woodchips have an insulation value of about R-1 per inch.  As with other low insulation value materials, like soil (R~0.25), the insulation is negligible over a small thickness but really adds up over a deep thickness.  So the center of the pile can get quite warm, thereby increasing microbial activity, generating more heat, and so on in a positive-feedback loop.  This can create a very hot core, probably too hot to be ideal for most fungi, (although I understand that higher temperature bacterial growth, or even reaching a sanitation temperature is often part of a composting process).  Putting water on this will cool it and spread the heat outward.  The temperature of open water often tends to self-regulate to around 80°F, since this acts like kind of a threshold for the evaporative cooling rate.  

As the composting progresses, the inward flow of materials is a fairly optimal design since new material can be piled on the outside, although removing compost from the center may require digging into the pile or having some other arrangement to get around this issue.  

Many folks, if not most, use the chips as mulch since the mulch keeps down the weeds, the time and labor of having to move materials may be less, the land use is more efficient (at least if you're not harvesting mushrooms), and the composting conditions are still good.  The thermal mass of the ground helps moderate the temperature.  Rainwater is naturally distributed.  A layer of chips several inches deep probably increases the soil temperature significantly, both helping the plants and the composting process and retaining moisture, and producing *a lot* of soil.

The advantage of a pile is that chips are often delivered or produced this way.  And they may compost faster in the off-season assuming the geometry causes the core to be kept warmer.  However if you had another source of insulation and/or heat, like a solar greenhouse (or some sort of cover), then it may be more optimal to spread the chips evenly over the ground.  

So my current locale for the business side of my life (poultry+produce) is an abandoned dirt parking lot that sat dormant for about 35 years.  

I've worked very hard over the past decade or so to obliterate any remnants of my box... if I don't have one left, I can't accidentally limit my thinking to inside it.  

One of my hare-brained ideas that I haven't yet been able to try out is this.  Hugel-beds.  Most here will be familiar with the idea of hugelkultur, burying logs with dirt, carbonaceous, and green detrius.  My idea was that the same principles would work if the logs were not intact.  Effectively, creating beds of an appropriate width (4-6') and length (25-50') of chips around a foot deep, then burying them over the course of the year with all of those pesky waste streams that would otherwise be landfilled... grass clippings, leaves, etc.  

Strikes me that an 8'x4' trailer full of chips could build a 4' bed 32' long at a 12" thickness.  Add one or two similar loads of yard waste, and voila.  If you can manage to build the beds before winter sets in (we get a few early frosts before the grass actually goes dormant) the beds should be sufficiently broken down by May to put produce varietals that require "dry feet" like squash, pumpkins, cucumbers, etc.  Then of course, when you get plant kill the next fall, you simply shred it back into the beds to compost/break down over the following winter.  

Hi Chris, that sounds like a good way to compost wood chips and other materials.  I believe I've heard Paul say (in a loudish voice) to not put wood chips in a hugelbed.  Since they're chewed up they don't work the same as a big spongy chunk of wood.  I'm guessing (or I heard) that the chips consume a lot of Nitrogen as they breakdown (compost?) so there isn't much N left for growies.

So my suspicion is that a bed as you proposed would be pretty good for generating biological decay and compost but maybe not as good for growing things.  I also think hugels are usually covered with some topsoil.

Once in a performance review I was told that I think outside the box that the box is in.  I believe that was a good thing, I'm not sure they did...

Mike Phillipps wrote:(Note: making "char"/"charcoal"/"biochar" doesn't create compost or nutrition for plants (it destroys it actually), so whether it has other advantages or not I can't recommend using any sort of thermal decomposition

Mike, perhaps there would be some nutrient loss if using sapwood and if the Biochar is made at too high a temperature, but Biochar should be made at around 500C.  At that temperature all the minerals should be retained.  While the wood itself is food for fungi, it's not nutrients (other than the minerals that are not lost by Biochar making) for plants so I'm just wondering what you mean by your comment?  What Biochar does really, really well is to preserve nutrients that would otherwise be lost in composting processes.  Adding 10 or 20% by volume Biochar into the blend of compostables leads to a strong reduction in the loss of nitrogen to the atmosphere and minerals via leaching to the ground....thus a richer compost with extra benefits lasting up to 1000s of years.  The composting process also proceeds faster and gets to higher temperatures with Biochar present.  Biochar and soil organisms have interacted together in the soil as long as fires have burned fields and forests....millions and millions and millions of years.  Biochar contains functional groups that have been shown to support oxidation and reduction reactions carried out by bacteria and reduce the "cost" of metabolism leading to much healthier soils.  Biochar also can improve water retention and drainage.  The richest soils on this planet, tropical or temperate, contain high levels of Biochar, either by human creation or by natural fires.  Beyond all that we really could use sinking a lot more carbon and Biochar is a great way to do that.

I can't imagine composting, mulching and gardening in general without biochar.  I've been using it for 11 years now and my gardens are really doing great.  Side by side beds with and without biochar show obvious differences for me.

My theory, Mike, revolves around the compilation of numerous approaches, both comtemporary and historic, to improving soil quality.  It is paramount to my success in production of greenies to rapidly revitalize an acre lot which was scraped, leveled, was the home to a school parking lot for approximately 25-30 years before being abandoned to a weed choked, barren wasteland that is excessively compacted (2" of diggable depth with hand tools) and extremely difficult to work with.  

In looking at varioius means and methods to improve soil quality, I noted several methodologies which held promise.  Hugelkultur, for example, converts raw inputs into good quality organic material, but requires up to a decade to be successful.  Lasagna gardening creates suitable beds, but it works best with decent soil parameters as a base, which I lack.  Tierra preta would be an excellent thing to have, but I don't think I have that kind of time.  

Then it occured to me that building composting beds might be a solution.  Build it like a hugelkultur, with a good layer of carbonaceous material covered with green manure and topped off with yard waste (out here grass clippings dry out quickly because of our ambient humidity & temps.)  Setting the bed up in the late summer would allow it to cook over the course of the fall & winter, and begin planting the following spring.  

I'm not positive, but believe that the manure, particularly from animals on high moisture content feed (cow patties from cows on fresh grass are very wet compared to hay fed winter patties,) will effectively innoculate the wood chips to help prevent the nitrogen drain you foresee.  

It may be crazy, but it just might work.  If not, it will still provide plenty of augmentation material for more traditional permy approaches.  

Woodchips do best top-dressed (not buried!), ideally after functioning as bird litter (Back to Eden style), or I have used duck pond water with great success to inoculate piles and provide nutrients. You can do this with just a plastic tub and a couple ducks.

Wood will consume Nitrogen within .8mm of its surface for up to 3yrs. Due to the geometry and surface area to volume ratio of the wood used, either
Poultry-worked-woodchips on top of the soil (back to eden style), or
buried pieces of all sizes up to 2ft thick or more, (hugelkulture), create a negligible Nitrogen deficit that is outweighed by the benefits quickly.  Once you have fungus fixating 150-200kg/ha of N, like it can in healthy forest soils, you quickly counter the initial (1-3yr) deficit.

Burying woodchips will create a multi-year nitrogen deficit (I have made this mistake in the past). Woodchips are not like small twigs, which have high amounts of sugars and nutrients due to a large amount of cambium relative to their mass and volume. Woodchips on the other hand often come from older, more carbon and tannin rich heart wood that is meant to stay stable for as long as possible even after the cells of the wood die, because it functions as the support of the tree. If you know the woodchips come from pieces 3-4" or less, that is ideal and will cause no N deficit at all as a mulch. I still would not bury them.

I do hugel beds with 4-6" of woodchip mulch that has be broken down in the bird yard for 6 months. This seems to get the best of both and I don't have to water unless I am seeding in the summer, which usually gets almost no rain (<1") for 4-6 months. I think whether to use the wood as chips or hugel material (if not a higher use beforehand), comes down to whether it is easier for you to chip it or bury it as it falls.