Wet Anaeroblic Rot Compost: Sodden Sod.

Hi all.  It's been a while since I started a thread, so I thought I'd actually let you all know about a project I'm working on: Composting weeds, including perennial grasses with dense or vigorously spreading root systems.

I have a pretty rough last couple years, and my mental/emotional self has not been up to a lot of tasks.  I won't bore or burden anyone with the details of that, but my garden went to crap (weeds), a little (read as: a lot) beyond what I'd like.  Perennial weeds like grasses, daisies,hawk weed, eye bright, as well as some tenacious many seeding annuals like hedge nettle have a way of taking over growing space, especially if left unchecked.

I'm on a leave of absence from work and have gotten, with the help of my mother, most of the garden back to a relative state of control.  

The pile of weeds was impressive.  It filled a full sized truck to heaping but before that it was just in a massive heap on the garden side.  I know that a lot of these would not benefit a compost pile much, and are in fact very difficult to compost, so I decided to try something new.  Do a controlled Pre-Rot.    

I went to a local dude who farms cattle and garlic organically (not certified), and got a truck load of this year's manure which was half from his cows winter water hole, and half from the winter feeding rack area: a mixture of hay and shit that was scraped up in a pile to the side.  Half of this truck load was laid in with the weeds on the heap.  

I chopped the weeds up with a sharpened spade as dad hosed them and the manure down. A chipper shredder would have come in handy here.  So what I mean is dad saturated the pile while I went at it with the spade like I was a machine.  It was cold out.  Dad was wearing two sweaters over his shirt.  I was shirtless and sweating.  It was a good workout.  

Anyway, the truck and a half of material, wetted down as such, was actually reduced in volume to less than a truck load of volume as there was virtually no air in it.  I also added about a half truck load of grass clippings, half of which was green, the other half part dry.  I expected and wanted an aerobic rot, rather than the sort of compost that I normally make (and indeed, right beside it was a proper compost, made with plenty of air, and only dampened, rather than soaked, was one about twice the size).  The entire pile was covered with six or more inches of grass clippings to reduce light, and air and hold the moisture.  

A week later (Today) I turned both piles.  

My intention was to get another load of that great manure mix and add it to the anaerobic pile, but the dude wasn't feeling well, so I'm waiting on going over there.  But the piles were still hot and I wanted to keep them generating more heat, so I decided to not wait.  Dad does the maintenance at the school yard, and so after he mowed, we went up there and raked up more clippings.  So instead of manure, I added more grass clippings.  These I try not to lay too thick all at once, and I go at them with my spade fork, with a plunge and twist, so that they mix with the sodden material.

So today's task (which is to begin the transformation of the pile towards a more proper aerobic compost heap) began by removing the outer layer that is not as rotted down.  Oh and the six inches of grass clippings I put to one side, near where the new pile would be.  The actual sodden sod mess, I stripped downwards with the spade fork.  This outer material will make up the center of the next stage of the pile.  It had some break down, some things were growing out with some fresh growth toward the outside... so there is plenty of composting/rot work to be done to this outer material still.  The outer top, was hot, whitish like ash and (I think) steam dried after going fungal.  At any, the rest of the outer layer was warm but not hot.  Not much vigorous chopping was needed; I was surprised.  The smell was also surprisingly not too bad (I expected it to be pretty gnarly and rank).  It was in fact somewhere between compost and wet manure in smell, even in the center where it was dense, anaerobic, saturated, hot, and in full rot action.  

I wheelbarrowed from the far side all of this outer material, and from the near side, spade forked directly onto the new pile location, mixing it with the spade fork twisting motion with grass clippings. Occasionally I would spray some water, as the outer layer had some surprising drier areas (particularly on the sunward and windward sides), and some of the grass clippings that I was mixing in were dry.  

Generally for this stage of the pile I was not planning to give it much water>  In fact I didn't even have the hose over there yet, but it actually needed a bit.  If I had the new truck load of manure I would have probably mixed the center and outer layers alternating with a layer of manure and only (maybe) sprinkled the manure/hay mix, and this would have given the outer layer material plenty of moisture.  I also added about three big wheelbarrow of hay to give it a bit more air - I did want to go towards a more aerobic pile but I didn't want anything to start growing, or I might have added a lot more of this loftier material.  There was a lot of root material in the new inner core, and I wanted this to still rot a bit... so combining aerobic and anaerobic methods here.

The inside core was difficult to work with.  It was heavy work lifting fork after fork of the dense saturated manured hay and sod, but the majority was seriously rotted, and broken down!  I did notice that the very bottom foot of it was not really broken down much, despite being equally saturated and dense; I figure it was because it just didn't get hot like the center did where the thermophilic bacteria were really communing.  

This core material would now, of course, become the outer material, and was mixed with the previous outer six inches of grass clippings, and some new grass clippings, some of the former of which was flattened into dense mats.  Some of the mats were whitened with a fungi, and others were slimy or nearly so.  I tried to use the spade fork twisting motion to break these up when mixing with the fresh clippings and sodden inner material.  No new water was added.  

Generally I was just throwing this material up onto the top and hoping that it would cascade down the sides of the new core.  The density of it, however, dictated that I often had to break it up the large blocks of dense material and the matted grasses with the spade fork a lot more than I really wanted to have to do, but oh well... it was also broken down more than I thought it would be and I figure that I owed it something... or something like that.  Back to work.

Afterwards I covered the entire pile with about two feet of grass clippings, to cut out light, reduce external oxygen, to shed excess water, and to also keep the moisture level about how I made it.

In about a week I will probably do the whole process again, but this time with a final addition of alternating manure layers.

My regular Aerobic compost will probably be done with the next turning, but this one will probably have two or more additional turnings, as I go more and more aerobic with it for the finished product.    

In the end, I'm hoping for about 4 tons of compost.   !!!                  

Great post Roberto, wonderful details on how to work a compost heap and what to watch out for.

Redhawk

Thanks, Bryant.  I was hoping to be a bit more brief, but, in the end, I figured the details would be worth it for other readers.  I believe that it's often thought that such plants can not be composted.  I thought that I would document the process, so that people understand that even tenacious grasses can be broken down and made to compost, if only given the right conditions.  If you, (or anyone else) have any suggestions on improvements to my method, I would greatly appreciate it.  

As I mentioned, a chipper shredder would be an invaluable asset in such a production, not only saving that initial chopping labor, but also reducing the root mass of the grass clumps, and increasing it's broken surface area for biological breakdown/compost action, thus decreasing the time that the process would take and possibly further reducing the need for labor on a final turning.  

I think the chipper/ shredder would lock up from the root masses getting between the hammers (flails).
( just going on the design of my chipper machine)  and the way green leaves can stop it up so that I have to turn it off and open it up to clean the hammers (flails) so they will turn again.

There is one machine that I would love to have that would do this job very quickly and that is a Hobart Chopper.

It would only take about half a minute to process per bowl (these things hold over 40 lbs. at a time.
You can take whole beef muscles and turn them into meat paste in under 2 minutes, vegetative matter won't clog them up so a big mass of roots to fine bits in about two turns of the huge bowl and done.
The hold back is the costs of one of these wonders.
I am trying to come up with a design of something that would work in a similar fashion without being super expensive to build, just for composters, I think it would sell fairly well.

Interesting machine, Redhawk.  I'm thinking of building my own shredder.  My thoughts are to make a wood gasifier that would power my old beat up farm car, which would have it's front end up on blocks.  One of the wheels would be removed and the lugs would be holding a shaft that went to the chipper.  I have been working on the railway, and there is an almost endless supply of this particular chunk of metal that may act like a sheer pin somewhere on a box car.  I don't know where it comes from on the trains.  Anyway, the track is littered with them, and they are almost the right shape for using as heavy but small flail hammers.  All they would need is to be ground sharp on one edge.  I have a two gallon pail full of these at the moment (probably 20 or 30 of them), and I figure the shredder might use 8 or so at a time, with lots of replacement parts.  

The manure guy called and said he had another guy coming for manure this morning, and so off me and dad went with two trucks to get some too.

I was just going to heap it to the side of the piles, but I decided in the end to use the fresh stuff from the winter water hole, and the stuff that is mixed hay and manure from the winter feed trough onto the existing wet rot (transitioning toward aerobic) heap.

I had the hay/shit mix as a final loader bucket full on the big truck which also had three scoops of heavy black aged manure.  

The smaller truck took two scoops of the pure stuff from the water hole.

Both trucks were not pleased with the burdens, but the haul was short.

We took the two feet of grass off the pile and then, in layers from alternating trucks, I added to the pile, while dad sprinkled it down with the hose (or took breaks in the shade).  It is about 83 F /28.5 C, and right now it is beer o clock, well earned.  I worked steady for several hours (it took a lot more time because I was removing grasses with roots as well as stones that came with the load), but in the end I was very pleased with the resulting heap, and since I had so much grass present, I was still able to cover the now much larger pile with about a foot of grass.  

Oh and the pile underneath the grass was cooking hot already after only a few days.  

Just because of the size and that I don't have a tractor, turning this pile next time around is going to be a workout and a half, but I have a feeling that, in a way, it will be somewhat easier since I added a lot more air and broke up the material more for the composting process and this will have made the material have a lot more friability than the last time-which as noted above (the core) was heavy wet and clumpy to deal with.  My hope is that the heat (and heavy microbial action, and increased oxygen), is doing it's magic on those tenacious roots and that this next turning, with all of this manured hay and pure manure already activated, will really get this pile working in a powerful aerobic super compost.  I know my own body is super oxygenated after today's workout!  

I broke some new ground where I had overwintered my laying hens. So it was chicken manure, low quality hay and wood chips on top of sod. In other words an compact anaerobic tangle.
I first used a matock to break it up rough then a cheap light weight electric tiller and a bow rake to break it further and bring it into a long mid thigh high pile.
The tiller worked a treat also for turning the pile along with the rake. Since the tiller is so light you can run it sideways along the pile with only a light struggle. If you try it, don't bother trying to dig the tangled sod rhyzomes out of the tines when they get over loaded. Unbolt the tines and the roots come off easy peesy. With this method our garden should grow by leaps and bounds over next few years.

Hi Bryant.

I take it that the Hobart chopping bowl machine has a rotating bowl as well as the blade turning?  What is the approximate RPM's of the bowl and the blade?  Is that bowl a couple feet across?  

Hi Alley.

Interesting thing you are doing.  Let us know how that works out with all the sod bits tilled into the long mound.  My experience with that sort of thing, is that tenacious rhizome spreading grass clumps will re-grow, and spring up from the little bits, and the rhizome growth can be quite long.  That said, the tiller will kill off some, and you will get a lot of fertility from mixing this in with your chicken and hay bedding.  From what I learned with this method you described, is the more I kept up on the perennial growth in the first year of establishing a bed, the better the system worked.  Good luck with it.

Yes, the Hobart Buffalo chopper bowl turns at 22 rpm and the blade spins at 1725 rpm the motor is 1/2 hp. (they make bigger ones (1 hp.), I've seen them, they take up the space of a washing machine.)
Width of the machine is 31 7/8 inches, The bowl shown will hold 5 lbs. of meat. (level with the rim of the bowl) The thing will chop fine enough to make hotdogs or bologna, and it only takes about 2 minutes from whole chunks to super fine.
It made fine chopped (under 1/8 inch) compost in less than a minute out of twigs, green leaves, half dehydrated sheep manure, fully dehydrated cow manure and wilted comfrey leaves (10 lbs. total weight, and it all fit in the bowl at the end of the one minute run).

(I was kicked out of the kitchen (won't say where) for life, for using one of these to process some raw composting materials (listed above), got caught by the chef and he watched me clean it to his satisfaction)
It was worth it, I found the buffalo chopper to be an ideal machine for the purpose I used it for, even though the chef was not impressed. (It took me over an hour to satisfy his standard of cleanliness)
I was informed that it was a 10,000 dollar US machine (turned out to have been brand new, so my bad)
Interestingly enough I ended up growing most of his vegetables for that year (for free) so I would be allowed to enter his establishment.

The Hobart chopper shown is a new style machine... It will have a bowl of either 14" or 18" in diameter...
The knife shaft rotates at about 1000 rpm, it is belt driven ... The older models of this type of machine had 1 hp / 3450 rpm motors...
The bowl rotated at about 50 rpm, gear and belt driven...
Here in N Carolina they are known as "slaw cutters" or "bbq choppers"