Microbes Need Mulch That Rots: CTAHR's Field Trials

0:02 Vincent Mina: Okay. Okay. So, um... And then tomorrow night we have the movie. Have you all signed up for that? Okay. And we have Senator Russell Ruderman going to give some remarks tomorrow night. You know, next year we're having our state convention. Hawaii Farmers Union United is having a state convention next year here in Hawaii. so we're not sure where it's going to be, but the center is kind of nice, huh? Kind of centralized. What do you think, Steve Sacalo? We've got to get together with all the chapter presidents and find out where you guys hold the convention next year, yeah?

0:45 Audience: A little far from me.

0:46 Vincent Mina: Yeah, a little far from you. I get it. Yeah, yeah, yeah. And so, you know, if anybody wants to make the trek to Maui, November 13th through 15th, we have our convention happening. go online to hfuuhi.org and so as a show of hands how many people weren't members of Farmers Union when you came to this symposium? And are you now members? Thank you. Thank you. I appreciate it. So Dr. Koon-Hui is a researcher with UH Mānoa, and she's going to talk about natural farming

1:34 and her research with natural farming. And please listen closely to what she has to share. She's a bright young mind and committed to her work. So please give a warm welcome to Dr. Koon-Hui.

1:49 Dr. Koon-Hui Wang: Thank you for including me in this great symposium. Thanks for staying for so late. I will try not to be too long, although I have many slides to share with you. I started working on Korean natural farming since 2010 when I first attended Master Cho's seminar. and Mike DuPonte has been asking me to check out the soil health related to this. I'm really a plant pathologist, nematologist and now my position is sustainable pest management. So why am I included in this talk? Most of you here

2:34 have already practiced Korean natural farming and you have more experience than me. I just have one skill that I have been using a lot. So I use nematode as a a soil health indicator. So basically I just rely on what the nematode tell me and so you see the result from what the nematode is telling you. So just a summary of what see the result from what the nematode is telling you. So just a summary of what Korean natural farming basic principle is. It involves collecting and culturing the indigenous microorganism from your natural area close to your region and

3:13 and reintroduce them into your agricultural land that you have heard that we have been killing and disturbing the soil and all the soil food web have been disturbed and so Adam Reed have been brief you on all this importance of soil health and so the concept is using the IMO that you culture and then to enhance the soil nutrient cycling and this is what I'm going to emphasize a lot throughout the talk here. Basically you are recycling nutrients. All the crop residues from last season or any leaves that drop down, it's about

3:48 recycling your soil nutrients. The IMO by itself is not sufficient. The amount that we put in is so little, which is great because conventional farming you might hauling in 10 tons per acre of compost and that's expensive to how also heavy compost. But if you calculate what IMO you apply in a natural farming protocol, it's less than half a ton or 1,300 pounds. So this is way less than the 10 tons that we have to apply as a compost. So you want to help the plant to produce healthy root system for efficient nutrient cycling. So the other part of what IMO do is to help your

4:28 plants roots to grow well with lots of mycorrhizae to absorb all the nutrients that are harder to absorb if you don't have a healthy root system so this is a main concept so nutrient extract from various fermented farm waste is the other part that you guys have been hearing about how to make the foliar spray spray weekly and this is the only nutrients inputs from this practice so So the IMO is just to help the plants to grow better. So for healthy soil nutrient cycling system, you have all the crop, either crop residues, or you can add mulch to the soil surface,

5:07 or it can be growing a cover crop. But all these nutrients is not readily available for the plant to uptake unless they are being partly decomposed by the fungus or bacteria, and then they will turn into inorganic form, and then this inorganic form will be available for the plant to uptake. But during the fungal or bacterial decomposition process, they also have to maintain some nutrients for themselves, so they will tie up some of the nutrients in the bacteria and fungi. So to better recycling them, you will have to have bigger soil fauna, bigger organism in the soil.

5:45 They will eat the fungus and bacteria, and when they recycling out then more nutrients will turn into inorganic form so this is where I my nematode come in handy I have bacterial feeding nematode that feed on bacteria fungal feeding nematode feed on fungi and we also have bigger nematodes like omnivores and predatory nematodes that recycling more nutrients that was tying up on the smaller nematodes when this happened then you have a good soil nutrient cycling a better soil food web and and that's why we want to have a healthy soil health system. But all this nutrient cycling would not happen

6:23 if you don't have any organic matter for it to recycle. So this explains why sometimes Korean natural farming works very well in one area, sometimes it's not, and so it all depends on what kind of nutrient is available for it to cycle. So you have crop residues, it's one type of nutrient that it can cycle out, but it all depends on what kind of material available in your area. But not all material are easily decomposed by bacteria, fungi, and so that play a role.

6:55 So I've been, during this last five years since 2010, I have contact, different people contacted me to test whether it's working or not in this area or others. So I have more than 10 field trials, 7 of them mostly are comparing if Korean natural farming is better than organic farming or is it better than conventional farming. Some of them I actually test with or without the mulching, how important it is to have the mulch while you are practicing the natural farming. So not just IMO by itself, whether we should have the mulch or not is what we were testing.

7:32 One field trial I actually compared IMO to other commercial soil inoculants but some field trials totally failed because it's not magic and if we didn't do other things right it just doesn't work out. So I give only a few examples of what I did. So I list down what crop they use and mainly I want you to focus on what mulch is used in this different system. So the first example was this farmer she used she grew sunn hemp cover crop for two months and then she did a no-till which is so when Adam was telling you the full concept of NRCS promoted how to maintain soil health the first

8:20 tool is you have to keep your soil cover all the time so this is where the Korean natural farming are telling you to use mulching along with your IMO block the sunlight from burning out your IMO after you introduce it the other part is natural farming actually also highly encourage you practice no-till as much as possible especially after you apply your IMO for so natural farming are quite compatible with all the soil health for principle of soil health maintenance so in this first farm so after she grow the soybean subsequent to the sunn hemp cover crop so this is the different so how green

9:07 color you can see here just visually you can tell is different and you can see this is a Korean natural farming plots over here is darker than the one and the conventional obviously her farm the natural farming works very well in a farm situation and so I measure the soybean biomass the dark one is Korean natural farming higher yield than the conventional so she was using ammonia as a synthetic fertilizer in a conventional chlorophyll content so we actually not just rely on eye measurement but we measure it with a meter that measure the

9:46 chlorophyll content darker in the Korean natural farming and even the nitrogen content in the leaves was higher. So it works and so using nematode as an indicator it also works so we want all the beneficial nematodes to be high so bacterivores is higher, fungivores is higher, omnivores when I mark this is statistically significant so they actually increase the omnivores and predatory nematodes. Nothing in the conventional in the first year. I was surprised by this because when I do conservation practice with cover crops,

10:26 so I do lots of cover crop projects, I won't see increase of, significant increase of predatory nematodes usually until second cycle because it takes time for them to build up. but it speed up the soil food web build up process by introducing IMO, indigenous microorganism The other thing I consistently observe is that whenever you introduce IMO, you will improve your soil tilth Soil tilth means how soft your soil is, so we have a compaction meter that looks like this put it down the soil after the IMO treatment to check how deep the soil probe can go through So

11:10 So this is this measurement here. So that is much deeper in the Korean natural farming versus conventional and also while I'm extracting the nematode from the soil I also see other soil fauna that come out. So one of them is the enchytraeid worm This is a little cousin of earthworm. So you don't always see earthworm after disturbing the soil for a long time. But enchytraeid worm tends to be more commonly found and it was much higher in the Korean natural farming. So this is from a farm that it works very well. So the second farm using wood chips. To say

11:51 yield wise we don't see difference and nematode communities also not too difference but again we see a same trend in terms of the earthworm and enchytraeid worms is much higher in a Korean natural farming so so bear in mind that this was wood chip wood chips is much harder to decompose compared to a cover crop especially like sunn hemp that has high nitrogen content from the soil compaction so this is from a third farm this is actually a permaculture farm from the Akiya and Puna area. Very healthy soil already so can the IMO further

12:31 improve it? When they try IMO 4 they didn't see any improvement in yield but they have to use the IMO 5 which means that you add animal manure to it and they did see an improvement in yield of the leek, burdock. Okay so so you can see they are very inconsistent results and so I'm trying to see if there's a pattern here so I come back to Oʻahu, this is Windward Community College they have a nice nursing program where they train the in training nurse to grow organic I mean grow produce organically to serve their clients so they're

13:12 healthy food healthy you'll be healthy patient so Jamie Boyd is who I work with So this is the IMO 3 that they made. They opened up very healthy. So they did invite Joe McGinn to come and give them a four-week course. So they were trained intensively. So properly trained. So we did a cherry tomato trial where they grow Korean Nature Farming versus organic farming and conventional farming system. So the mulch they use is [unclear] Hawaiian Earth Products composted material that we can buy in Oʻahu.

13:58 So yard waste compost is what they use. So they have Korean Natural Farming versus organic, Greenhouse Hawaii come to their farm and make wormy compost for them and they collect the worm casting, prepare the soil amendment and then weekly drenching of vermicompost tea. Conventional system is they just use a 16-16-16 soil drenching every week. So I just let the student do all the measurement for me. I only read the nematodes and they tell me the earlier measurement at six weeks after planting KNF tends to be slightly slower than the other treatments. And then later on I come at three months

14:44 after planting I measured the plant growth again. So they were the conventional and organic somehow very susceptible to septoria leaf spot as well as alternaria early blight. So they were declined already. While this is flushing and spot, I mean lots of fruit. Throughout this whole period the student also harvest all the fruit for me, keep track on which treatment income from so we have a yield data to compare and at three months I also measure the chlorophyll content again KNF works organic especially at two months after planting this is four months after planting

15:29 so significantly difference between Korean natural farming especially to the conventional treatment stem diameter this indicate the plant growth is also having same trend not too much at the beginning but more significant towards the end so I left again significantly different this is again enchytraeid worms or they probably have earthworm also so the main purpose is to so that the client will have healthier higher nutrition nutrition food for the patient So I submit all this fruit that they harvest to another scientist in CTAHR, Dr. Bingham, J.P. Bingham.

16:13 He has HPLC machine that can measure the vitamin content in the fruits. Unfortunately, we didn't really see better nutrient content in Korean nature farming. But I have to say the fruit size is big difference of good size tomato in the Korean nature farming versus a tiny bit of fruit so it might be all concentrated nutrient wise so it did not result in higher tomato fruit quality the conventional farming method produced tomato with highest amount of vitamin C which is the [unclear] and the lycopene is another nutrient content I also submit a sample to our ADSC to do

16:58 all the nutrient mineral nutrient tests and looks like organic has lots of the highest nutrient content but their fruits the fruit size is also relatively small but yield wise is just higher in the Korean natural farming. Brix test is actually intermediate for the Korean natural farming bigger in the conventional system. Brix is the sugar content test. So just one trial probably need to be replicated and maybe different handler might be different so need to be tested more frequently. So then Maui Robin Shimabuku

17:44 also asked me to conduct a trial over there in Kula Station and I just give them the protocol and the farm crew carried out the whole process. And they have lots of bamboo trees collection in that Kula station so I thought good this is a good mulch material since we use we like to grow our IMO under the bamboo tree so I tell them just use bamboo leaves as a mulch. That was one big mistake I did. So lots of leaves under the mulch and I even looked up literature there was one publication from India that look at what kind of fungus from bamboo needles so

18:26 they found all kind of fungus right yeah you can even look it up biodiversity 14 and lots of saprophytic fungi which is could some of this could be the white mold that we saw from the IMO so it shouldn't be bad using bamboo mulch mulch. They gave me a few plots that were fallow for a long time. They were all boxes before but nothing was growing. It was just bare fallow. They would keep the weed control very well. Ten years later, here we started an experiment. I planted three replications of each treatment, conventional, organic and the KNF. In the KNF, I would use the bamboo

19:10 mulch and so since I let them do everything they also say okay we'll compare most traditional standard practice will do we always drench the seedling with some fertilizer before they put it into the ground but KNF doesn't have drenching of fertilizer at the seedling stage except the SES that was right before planting so seedling was so small and you can see after planting you can see the conventional and organic but you can't see the seedling but it's planted in the KNF practice so they were started much slower so then we plant zucchini second year we plant tomato okay so this is how

19:54 it looks at at harvest termination of harvesting time two and a half months later so doesn't seems too different but the yield data is significantly lower in the natural, natural farming. And so this is why there are something different between the treatments. So damage wise, less fruit less damage which doesn't really bother the plants. Same thing in tomato. So all the, no seedling drenched with fertilizer for KNF but seedling were all fertilized early on, couldn't catch up. So you might say that okay let's just keep harvesting the KNF further so that we can

20:37 complement the time lapse and but they have severe fruit fly problem so if you left your field too long I mean if you let your crop growing there for long the fruit fly find your fruit already even you want to harvest much longer you will have lots of unmarketable fruit so chlorophyll content was still slightly higher in the Korean natural farming. Plant height was not so because they were started slower and the stem diameter is also not good in the Korean natural farming. So it was slow to begin with, lack of seedling treatment, delayed

21:16 the crop development, plant were greener in the Korean natural farming at the end of the trial. After two months of growth, fruit flies and pickle worm damage were already very severe so extending the harvesting time will only lead to more unmarketable fruit. So I would say that if there's something to improve on the natural farming maybe we want to somehow give some nutrients to the seedlings to let it have an early start to reduce the time exposure for the pests in the harvesting season. So soil health-wise, I mean the first trial, this field was

21:50 definitely very poor to begin with. I didn't even have predatory nematodes in in year one. But all of them are like that, no significant difference, but natural farming tends to have more bacterial decompositions, so more bacteria feeding nematodes to begin with. But soil tilth, like I say, is always consistently happen. Soil tilth is good, probably due to the enchytraeid worm. The field plot was fallow for a long time without much crop residue prior to the experiment, so IMO couldn't work because they don't have any

22:24 nutrient to recycle. So overall nematode abundance was very low in trial 1, indicating that this was starting with a very stressful soil condition. And the natural farming result in higher percentage of bacterivorous nematode, indicating that more enriched soil food web and KNF also improved the soil tilth within one cropping cycle, which is good. So this is just same data same trial just this is percentage significantly higher in Canada for data same trial just this is percentage significantly higher in KNF for growing crops keep nutrient cycling happen so beneficial nematodes will be

23:07 coming out so still bacterial was even organic was pretty high but nothing really significantly different but there was an indication here that predatory nematode amount was slightly higher in the Korean natural farming. But regardless of soil treatment, soil health is better in trial two than in trial one. So if we keep doing in the same field plot, we might see something better. So nothing was, so bamboo mulch is probably not a good mulch to use. So it's all lignified, all high cellulose, very difficult to break down for the IMO to work in one or two cycle.

23:46 And so then let's pay more attention to the mulch. So I do a trial. This is actually from one from David Wong's and he asked me to go visit his farm once in a while and I collected different type of sample. This is six months with mulch and he used Hawaiian Earth Products compost, yard waste compost as a mulch. When I take samples from this field, I have to be very careful because every now and then I dig the soil, I will find the earthworm and just loads of them after he has been mulching them and all treated with IMO.

24:28 All this has IMO, but without the mulch, way less compared to the one that has mulch. So it's not just IMO that is working. has to have mulching material to help it to build the soil health condition. So the effect of Korean natural farming is strongly affected by the mulch type and mulch use was the yard waste compost that is easier. It's already partially decomposed, easy for the microorganism to work on compared to the bamboo mulch material. So this is a trial I did in Poamoho back in Oʻahu. So I compare no-till sunn hemp with the till weed mat method. Both has either

25:14 Korean Nature Farming or just conventional. My conventional here is actually organic fertilized plot so it should be organic versus Korean Nature Farming but with sun hemp mulch or with weed mat. So weed mat will not have any organic mulch is just cover but still follow the principle that Master Cho recommend you want to block the sunlight from burning off the IMO and so organic fertilizer was chicken pellet 180 pounds of nitrogen and for the sunn hemp I even use roller crimper so this is an organic no-till practice equipment that you can

25:55 roll down and crimp down the sunn hemp and generate thick biomass. So I think I accumulated 10 to 12 tons of sunn hemp biomass during summertime. Oh, 14.7 tons per acre of sunn hemp biomass. So sunn hemp material and... So this is the stem diameter. So at the beginning, it doesn't... is the one that we like Korean Nature Farming with sunn hemp no-till practice versus a conventional which is the chicken manure fertilizer with the weed mat so this is the highest inputs you will expect them to be should have more yield

26:41 so initially Korean Nature Farming didn't match up with the conventional with weed mat but slowly this is three months after planting so it's just as as good as the highest organic fertilizer and weed mat inputs. So this is the Korean Nature Farming Cherry Tomato Grove. Chlorophyll content also as high as the highest inputs. So it's telling you that you don't have to add fertilizer. You will still yield as good as the conventional fertilizer inputs. Tomato yield, when I have AB, it's slightly lower, but it's actually pretty much the same.

27:24 Statistically, not different from the organic and weed mat, but look at the Korean Nature Farming with the weed mat that doesn't have organic mulch. It's not good. So they need something to recycle. So tomato yield in Korean Nature Farming with sun hemp was comparable to using organic fertilizer and weed mat, and KNF worked better if integrated with a no-till organic mulching system. You kind of see a trend now. you need to feed the soil. But one thing I noticed is we also think that current nature farming will end up having healthier plants and should be

28:00 able to resist lots of pests and pathogens but it's not a silver bullet if there are really bad pests in your field you have to somehow manage it with other pest management approach. Don't just rely on current nature farming to repel all the pests. And so we have lots of plant parasitic nematodes in the field site and we see that sunn hemp is known to produce allelopathic compound against plant parasitic nematodes so the Korean Nature Farming will suppress the reniform nematodes if you have sunn hemp so triangle with solid line will always

28:39 have lower nematodes than the Korean Nature Farming with the weed mat so So whenever you have sun hemp, you will have lower plant parasitic nematodes. So just to show you that you need some other tools besides Korean Nature Farming if you have to deal with pests. So just overall summary here, considering the amount of compost that is recommended by the Master Cho Korean Nature Farming at 30 pounds of IMO per 1,000 square feet, Literally this is like 0.65 tons per acre. The practice of natural farming is very feasible and very economical

29:21 compared to other organic farming practice that need higher tonnage of compost. Natural farming practitioner should consult experienced or certified natural farming instructor to conduct the natural farming properly. So if you face some challenge, talk to those successful farmers and I just heard David Wong, Chris Trump, and John was talking about they will never go back to doing conventional farming again after they figure out how to make the natural farming work. So natural farming will include not only inoculating the soil with IMO4, but also prepare IMO4 regionally using field soil.

30:05 You have to mulch and reduce the tillage as much as possible and you have to do foliar spray that provide additional nutrients that is needed for the plant to grow. However, inconsistent results in producing comparable yield to the standard farming practice, either organic or the conventional practice, it still occurs despite a proper procedure, and I think it is all due to the mulch. So this brought our attention to the basic concept of natural farming, that we have to recycle the farm waste, it's not just rely on nutrients from the IMO4.

30:43 Natural farming should be conducted in area with sufficient crop residues available from the previous crop or it can be if you don't have this is the first cycle you're growing the crop maybe you can start with a cover crop before you go into your crop production. My other projects are cover crop calculator and I comment I mean I consistently see there's big inputs of nitrogen from lots of leguminous cover crop and so that can be incorporated into natural farming. If crop residues is not readily available from the

31:16 previous season, careful selection of mulching material like the Hawaiian Earth Products or other compost Chris Rupp was using his ground up macadamia nut husks. So IMO4 is prepared through mesophilic composting process. Mesophilic means it's a composting process that doesn't allow it to go to high temperature. Conventional thermophilic composting temperature will go up 130 Fahrenheit or higher and that kills off lots of beneficial organisms also. The natural farming they say keep your temperature low. if it's too hot you turn it so that it doesn't burn off all the beneficial in

32:03 that condition similar to a wormy compost which is also a mesophilic decomposition you will have higher bacteria abundance than the thermophilic composting so this will better preserve and culture your indigenous microorganism associated with the compost it is not meant to be and the compost is not meant to be a nutrient source it's just to introduce the indigenous microorganism to recycle the nutrients so while proper practice of the natural farming could improve plant health it is also not a total guarantee of no pest problem main approach to manage the crop pests you

32:47 should still practice other method of integrated pest management nutrients inputs to enhance seedling growth could speed up the transplant growth so this can also reduce the time of exposing to lots of pests out in the field and in general as a good food producer we want to also follow good best management practices that could comply with food safety as much as possible this will make natural farming more competitive with everything that is going outside that is all I need to say and there are lots of people involved in this project over the

33:30 years and again I work closely with Ted Radovich and Jari Sugano, extension agent in Oʻahu. So the project was first funded by NRCS in the first year but it seems that after the first year I continue to have requests to do more research on it.