Investigation of 'layered' coco coir composting method

I have access to large amounts of sugarcane bagasse waste, which essentially consists of shredded bagasse fibres and pith. I am looking for a simple way to compost large amounts of carbon material that lacks nitrogen content, and most importantly, does not require constant mechanical turning. I came across this technique they use in India to compost coconut coir waste. Coconut coir or cocopeat, for those who are not familiar, in its original form is largely used as a potting soil amendment. It is very high in lignin (>30%) but some industries are composting coconut coir using this technique...

"The Tamil Nadu Agricultural University, Coimbatore India and the Coir Board, have developed for converting the coir pith into compost by using a fungus call Pleurotus sajor caju and urea. For converting one tonne of coir pith into compost, 5 bottles of spawn culture and 5 kg of urea are required. The raw coir pith (100 kg) is spread uniformly over a hard floor of cement, stone, slab or brick in a layer of size 5×3 m with a thickness of 10 cm. Then 1 bottle (350 g.) of the fungus culture (spawn) is spread over the coir pith. Another layer of 100 kg coir pith is spread over it and add 1 kg urea over the second layer. This process is repeated by adding the fungus spawn and urea alternatively with 100 kg coir pith till heap reaches upto a height of one metre. Keep the heap as such with constant watering and cover with a thin layer of coir waste to conserve moisture. After 30 days of decomposition, coir pith turns into a black mass of compost with reduced lignin, cellulose, organic carbon and C:N ratio. The volume of material is also reduced by 40 percent. In order to ensure moisture retention and protection from heavy rainfall and wind adequate shelter need to be provided to the heap."

The fungus spawn they use is basically a white rot fungi, pleurotus sajor-caju, also known as grey oyster mushroom. Final C:N ratio reaches around 23:1

I have some questions:

1) Do you think this method really works?
2) If it might, can someone be able to explain to me what goes on during the whole composting process?
3) Can I adapt this technique for composting my bagasse waste?

I like the sound of this method as you leave it in a rectangular heap for a month or two without turning, at least not till the very end, and it turns to compost.

I have some questions:

1) Do you think this method really works?
2) If it might, can someone be able to explain to me what goes on during the whole composting process?
3) Can I adapt this technique for composting my bagasse waste?

I like the sound of this method as you leave it in a rectangular heap for a month or two without turning, at least not till the very end, and it turns to compost.

1) yes this method really works, the use of fungi in composting occurs even when you don't really want it, fungi spores are everywhere there is unfiltered air.
Do note that they are also adding nitrogen in the form of urea, in alternating layers which allows the fungi access with out direct contact with very high nitrogen urea, it is more of a leaching system.

2) What goes on is that the spore multiplies and runs through out the coir and digests the cellulose fibers to use as food for the spore's growth.
The urea adds nitrogen, which allows the coir to heat up so the process takes less time than if it were a cold heap.

3) Yes you can use the same system to compost your bagasse waste.

Any of the oyster mushrooms will work in this system just as would the lion's mane fungi.
the concentrations of sugars, found in the bagasse waste should be a benefit to the growth of fungi, it will, however also attract other "critters" looking for a "sugar fix", but all will help in the breakdown process.

Everything he said, plus you could develop the system so that you have a tasty value added food product for farmer's market sales.

Or, you could mulch the fruiting bodies back into the mix once they are exhausted, and spread the entire mass out to add nutrients to depleted soil masses, as a remediation step.

Or you could use the fruiting bodies and mycelial masses as animal feed amendments which are very high in protein.

Or you could process the fruiting bodies for sugars and make ethanol from it.

Or you could partial process the fruiting bodies for sugars and set them out to feed bee colonies additional, natural sugars.

Lots of possibilities for fungi!

Thanks for the great replies. There are few concerns about this technique I hope you can help me address:

1) I understand why there are alternating layers of urea, in order to provide the pile a suitable C:N ratio to aid decomposition. However, at the layers where urea is situated, temperatures there will be high too I suppose. It could possibly reach 60 degree celcius when thermophillic stage takes over. Now, wouldn't this high temp kill off all the fungi spores at the layers close below, of if not, will retard their growth, as I understand the species of white rot fungi are usually a mesophillic species, although I'm not too sure about this?

2) By scattering the fungi spawn onto the waste material in alternating layers without sterilizing the coir waste, wouldn't this lead to high possibility of contamination of the spores, disabling its growth? As I know people who grow mushrooms, their first steps are always to sterilize the substrate. (sterilizing my substrate is not an option however, simply as there too much volume of it)

I made a small experimental compost pile, and added the spawn halfway through the composting process (not at the start, as illustrated in the indian coir composting method highlighted above). When I open up the pile a week later, I didn't really see much hyphae growth throughout. However, there might be few possibilities why things went wrong, i.e. I put the spawn only later during the composting process, or the spawn might not be a good quality spawn, or I keep turning the pile to check for growth every week or so, spores might be competing with composting bacteria, nitrogen might be depleted already, etc

I would like to try to make another experimental pile, but I would like some feedback from members of this forum before I try it again.

James Lam wrote:Thanks for the great replies. There are few concerns about this technique I hope you can help me address:

1) I understand why there are alternating layers of urea, in order to provide the pile a suitable C:N ratio to aid decomposition. However, at the layers where urea is situated, temperatures there will be high too I suppose. It could possibly reach 60 degree celcius when thermophillic stage takes over. Now, wouldn't this high temp kill off all the fungi spores at the layers close below, of if not, will retard their growth, as I understand the species of white rot fungi are usually a mesophillic species, although I'm not too sure about this?

The white rot fungi are thermophilic. Compostable household waste contains, together with vegetable material, varying amounts of papers and boards. Paper is made up of lignocellulose (as is coir and sugarcane) and it may contain up to 20% of lignin. Efficient degradation of paper in composting plants means that biodegradation of lignin is also needed. Currently very little is known about lignin degradation by mixed microbial compost populations (there are three studies in progress), although lignin degradation by white-rot fungi has been extensively studied in recent years. Organic material is converted to carbon dioxide, humus, and heat by compost microorganisms. It is assumed that humus is formed mainly from lignin. Thus, lignin is not totally mineralized during composting. The elevated temperatures found during the thermophilic phase are essential for rapid degradation of lignocellulose. Complex organic compounds like lignin are mainly degraded by thermophilic microfungi and actinomycetes. The optimum temperature for thermophilic fungi is 40–50°C which is also the optimum temperature for lignin degradation in compost.

2) By scattering the fungi spawn onto the waste material in alternating layers without sterilizing the coir waste, wouldn't this lead to high possibility of contamination of the spores, disabling its growth? As I know people who grow mushrooms, their first steps are always to sterilize the substrate. (sterilizing my substrate is not an option however, simply as there too much volume of it)

That is the idea, Every liter of air you breathe contains many different spores as well as pollens and other things. In a composting environment you actually want competition between organisms for better and faster decomposition of the heap. In a compost heap you are not growing mushrooms for food but rather for their decomposition traits.

I made a small experimental compost pile, and added the spawn halfway through the composting process (not at the start, as illustrated in the indian coir composting method highlighted above). When I open up the pile a week later, I didn't really see much hyphae growth throughout. However, there might be few possibilities why things went wrong, i.e. I put the spawn only later during the composting process, or the spawn might not be a good quality spawn, or I keep turning the pile to check for growth every week or so, spores might be competing with composting bacteria, nitrogen might be depleted already, etc

I would like to try to make another experimental pile, but I would like some feedback from members of this forum before I try it again.

Every time you turn a heap you are stopping the heating actions as well as disrupting growth of organisims. I don't turn heaps, I do use a 3/4" piece of pipe, pushed in to the soil below the heap, I do this all around the heap so that I end up with approximately one hole every 1.5 feet in every direction. This adds air to the heap without disturbing the workings of the bacteria and fungi. I do not recommend turning heaps except when the center shows signs of going anerobic (slimy core that is cool instead of hot), I check this by doing the aeration as previously mentioned, a simple way to see what is going on inside the heap. Far cheaper than buying a long thermometer just for the one purpose.

In India, the method they are using was tested for several years as they developed a sure fire way to decompose coir. Coir is rather like rice hulls, the material can lay on the soil for years with out decomposing at all. In the Northern USA mats of coir have been found that were laid down over 200 years ago and they are still in good shape with little decomposition.

Hi Byrant,

Glad to find out the pleurotus strain works best under thermophillic conditions. There was one confusing article that classified 'most' basidiomycetes (i.e. pleurotus strains) as mesophiles, but I also came across a few others reports that has lab-tests that proves pleurotus works best around 50C.

Like you said, if I do a new test, I think I should be able to get better results. Given that it will have a fresh source of urea nitrogen and high temperature to optimise fungal activity. And great suggestion about bottom aeration without disturbing the pile.

Another thing I'd like to do is add trichorderma spp to the mix. Because white rot primarily targets lignin and little cellulose. But trichoderma, being a brown rot, targets mainly cellulose breakdown vice versa. Do you see any clashes between these 2 fungi strains? Trichoderma infection is a big problem in oyster mushroom farm when it takes over. But in compost degradation, can they work hand in hand to break down the different elements, as you mentioned about competition being good? Will trichoderma perform well under thermophillic conditions too?

hau James, I can not see any issues at 50 C, that will probably be close to the upper limit of the heat up. I think you will find that the fungi establish their own territories within the heap.
In my own trials I have found that white rot fungi establish first and when they have moved on to new spaces the browns move in and feast on the left behind cellulose.
It is the earth mothers way, she lets each organism feast on what they love then they move on in the heap and another critter moves in to feast on their particular gourmet items.
I would recommend setting them up in different layers, that way they will co-mingle at their own pace. That would help with one not trying to wipe out the other.
Also by doing different layers of inoculation you will help the bacteria establish, there are bacteria that act like police to some fungi, keeping everyone happy and healthy instead of making war on each other.

I have one interesting red oak that fell several years ago, it has "zones" which have different fungi doing their work. I have so far documented that the white rot (lions mane in this case) seems to come along after the Jew ears and turkey tails have exhausted their preferred food stuffs.
What is interesting is to watch how each of these fungi move along the trees trunk, taking up to a year before they move onward to a new position on the tree trunk.
When I first found this tree, fallen in my forest, I expected to see different fungi but I did not expect to see the actions of myco. movement along the trunk as is happening.

I'll certainly try alternative layers of white rot and brown rot fungi as you suggested. But i will need to figure out how to do the new layer sequencing. But I'm also curious if you simply mix the white and brown rot innoculants together, which i have come across a research paper that did this. They mixed the different fungi into a cocktail compost activator. Im thinking that the possibility may be because white rot feeds on lignin, and brown rot feeds on cellulose, so they don't get in each other's way despite close promixity. What are your thoughts? If I could so this, then I need not figure out how to do the new layering sequence, and use back the original formula.

Certainly you can do that. Your thoughts are correct in that the two organisms do not compete for the same nutrients from the same source. In fact what would happen in such a case is that the white fungi will make the food for the brown fungi easily available. At the same time the brown fungi will make other nutrients available to the white fungi. A true symbiotic relationship.

On Buzzard's Roost we have approximately 25 different fungi occurring naturally. I take specimens of all of these and blend them up to inoculate the soil around our orchard trees, the grape vines and the vegetable gardens.
Occasionally we have fruiting events that appear like they are attacking the stalks of our vegetables but when you wipe these stalks down, it becomes apparent that no harm is being done, in fact the opposite occurs.
We are still getting new peppers and rattle snake beans and the strawberries are setting fruit again, right now. The newly planted lettuces are taking off and the brassicas are going strong, all helped along by the mycorrhizae present.

We have two mulberry trees that are only one year old, the trunks have grown from 1/2" diameter to 1.5" diameter in drought conditions, they also went from 2' tall to 4-5 feet tall and are branching nicely.

The fig trees are putting off a second crop too.

When I take a plug sample of the soil around any of these, the number of hyphae present is phenomenal and these reach down to 20 inches in some places, 18 inches in most places.