Field Broadcasters and Soil Chemistry



Field Broadcaste​rs and Soil Chemistry

Hugh Lovel

Dear Eddie, I’ll try to respond to your long letter in as much detail as I can. I want to let Shabari in on the discussion as she will learn more about the chemical/mineral side of things that way. I had your problem with the disappearing boron back in my early days, where I put B on and it disappeared and I put more on and it disappeared and I split applications and it still disappeared. It went somewhere, but where did it go? Not into my crops—they tested deficient too. It wasn’t until I got onto mixing my boron into my composts and humifying the boron (storing it in large humic acid molecules) that it stuck around and became available to my crops. One learns these things the hard way it seems—the agricultural colleges and institutes are mostly in the pockets of the fertiliser industries, so they tend to be very weak on information that will save a farmer from buying more and more fertilisers. I also learned, the hard way, that biodynamic horn clay greatly enhanced the utilization of boron by plants and the stabilization of boron in the humic fraction of the soil. Over the last six years I’ve had good success in recommending to growers (especially those with low soil organic matter and chemical nitrogen inputs) that they put their boron out with humic acids, either as dry boron/humates or as liquid with liquid humic acids (NTS sells a dry granular boron humate that is 10% boric acid, but you can mix as much as 3 kg of solubor with 10 L of liquid humic concentrate (per hectare) and apply with water with good effect. In compost, which is probably your ideal way to apply B on your farm, you can adjust your concentration of solubor to where you have 3 kg of solubor in however much compost you spread on that hectare. I would not, however, that 2 kg of zeolite per ton of compost probably isn’t enough clay in the mix. Zeolite is a super clay and a wonderful builder of CEC, but to ensure sufficient clay for substrate for your humification microbes to live on and build clay/humus colloids I would add some other source of clay or loamy soil (about 10% of starting materials). In terms of making compost, you’re sure to have plenty of microbes present. The ones that predominate is rarely determined by adding microbes, but rather by adjusting the composition and conditions of what you are composting. Your mix of materials, timing and conditions of turning, moisture, carbon dioxide/oxygen, temperature, etc. all influence what sorts of microbes take over. For example, adding clay (and zeolite is wonderful but how cheap is it?) can really boost the all-important actinomycetes which tie up loose nitrogen and promote an end result rich in nitrogen fixing microbes that are poisoned by soluble nitrogen compounds. Certain herbs and residues promote certain communities of microbes too. For example, if you have a source of nettles this can be a wonderful balancing input in terms of green matter even at one part in a hundred (10 kg/ton). Grasses supply silicon and legumes calcium. Various herbs concentrate different minerals, such as copper, boron, zinc or manganese. You may have to sort out what your local weeds are doing. You are always better off making your trace minerals biological by adding them to the compost before applying them. Compost is food for your soil microbes and thus it is held on to and supplied to your crops with little or no loss. You want to manage your carbon/nitrogen ratio at somewhere between 25:1 to 30:1. That can help to minimize both methane/carbon dioxide loss and ammonia loss. Turn by 65 degrees C, or 15% CO2, and keep moisture up to 50% and keep compost covered. Biodynamic preparation patterns can be an enormous help with balanced, beneficial microbial activity, and you would get that from a properly operating field broadcaster with all the prep patterns in it. When you have good compost—even at only 1 to 2 tons per hectare—along with the biodynamic preparations and good biological management (which includes keeping vegetation growing as much of the time as possible, including on your headlands, banks, laneways, etc.) it can and should get to where you phase out nitrogen inputs altogether. My rule of thumb with conventional growers in conversion is when/if the grower thinks he needs nitrogen then he will need nitrogen. It’s been my experience, the hardest thing to change is the mind of the grower. Nitrogen inputs (in soluble form, not in humified compost) inhibit nitrogen fixation—full stop. Apply nitrogen and you will need it because you will shut down nitrogen fixation. I’ve guided a number of heavy nitrogen users out of their dependencies by teaching them first how to apply nitrogen inputs with humic acids to tie up the soluble forms as amino acid/humate complexes and second to monitor nitrogen levels in their leaf tests so they cut back even on those nitrogen/humic inputs as they maintain nitrogen levels in their crops. This also requires developing a different eye for what colour green indicates proper nitrogen levels and amino acid N vs nitrate N in the leaf. The proper colour of amino acid N is both lighter green and has more of a glow about it, whereas you may be chasing too dark a colour green with present levels of N fertilisation. Even ammonium sulphate I never add without humification first. And there’s nothing wrong with a whiff of N now and then. For example, calcium nitrate, which is just about as soluble as can be, is a wonderful boost at the rate of 5 kg with 15 L of molasses as an herbicidal weed spray at planting. It switches all sorts of tall woody weeds off starting with thistles because it creates a flush of just the sort of microbes that tie up loose potassium at seeding and shift the balance over to sprouting of clovers. But at 80 or 100 kg/ha of calcium nitrate at seeding and nowhere near enough molasses to feed energy to the soil biology you can massively poison nitrogen fixation and end up with nitrogen shortages when filling out crops at the end of cropping cycle—plus setting up disease and/or insect susceptibility.  The fact is I like working with people new to farming on land that hasn’t had nitrogen inputs for 2 or 3 years and by leading them away from applying more than very modest N applications they go right straight to building nitrogen fixing capacity and never go the heavy nitrogen route with all its problems of leaching, insects and diseases. By never getting into heavy nitrogen dependency we can concentrate on balancing and enhancing present mineral issues in the soil that help natural nitrogen fixation work. It may make slow steps forward at first, but there are no backward steps, and once natural nitrogen fixation takes over all other problems generally sort themselves out. Soybeans are a great crop to get started with this sort of program. Ideally you should never give soybeans ANY nitrogen inputs unless you want to reduce or inhibit nodulation. But inputs such as lime, gypsum and rock phosphates—along with humified traces such as boron, copper, zinc and manganese, and possibly also cobalt and molybdenum—can be crucial to nodulation and yield. Soy loves a mineral feast. Boron two weeks before flowering commences can be a big yield increaser, but too much boron at sprouting can cause burning at seed emergence. But any way, add boron with humates, and boron works from the soil up so if you apply as a foliar you want it to wash off the leaf and get in the soil before it is going to do much good. Soy is so good for feeding nitrogen fixation that a kilo of soy flour in a 1000 L shuttle of compost tea brew will have it reeking of ammonia at the end of a 24 hour brew cycle. It will be brimming with nitrogen fixing microbes. The thing about both nitrogen fixation and P solubilisation is they take energy. However, the digestion of the microbes that fix N and solubilize P is releasing energy. Both ways this process requires P, so both the N fixers and the protozoa that yield digestion also have to know how to access P. So you get a soil cooking and soluble P levels will rise. If you let the soil relax a bit in good grass the actinomycetes will tie up the loose P again in humic complexes. Cobalt is used by the protozoa as B-12 (cyanocobalamine) to access these humic complexes, and a soil that contains good reserve P but doesn’t release it is showing it needs Co. Even 500 g of cobalt sulphate in a ton of compost should give the required Co availability to get the soil’s digestion and nutrient release going again. As for the BioAssay, the reason most things will lag behind the General Vitality is the GV is showing you what is happening when everything works together—the synergy. The whole is greater than the sum of its parts. When something is higher than the GV it is holding things back, but that doesn’t often occur, or not with many things. Usually everything else is lower than the GV. It’s the things that are lowest that reveal a need to boost them to raise the GV, but the GV SHOULD be higher than most other things. As for the pattern analysis, this is a research project of mine based on the different octaves of the periodic table. I’m trying to figure out what it means. Best wishes,Hugh Lovel