Coming along way after the fact, what an explosion of lovely thoughts, discussions and pictures! Makes me want to get my soil and closet back up and running even more
Thanks guys!
@Organic Sinse : it's lovely to get to see your grows and read about your compost concoctions again, such a pleasure!
I do have a few questions regarding the bark chips:
- what kind of bark are you using? It sort of looks like coniferous where I can spot it on the pix, but is it?
- any specific reason as to why bark and not wood chips?
The reason I'm asking is that a part of what I've been doing out there in the real world (urban landscaping) is to establish the use of wood chips from deciduous plants in lieu of those ubiquitous (coniferous) bark chips.
This comes mainly from a reasoning centering around ecological succession and soil conditions required for the appropriate groups of microbial populations in the soil for the plants we want to grow.
In terms of succession, the conifers are the last group of species to colonize out there in nature. Starting from bare soil, nature moves through opportunistic, flimsy weeds as pioneers, on to brassicas and tap-rooters who start conditioning the soil to greater depths, on to annuals, which on their more developed end include pretty much all our veggies - and cannabis. Then enter the perennials, grasses, row crops, shrubs, bushes, deciduous trees, and finally come the conifers, giving us our climax communities.
In each stage of succession, plant matter becomes more complex and nutrient requirements change, which isn't a problem since out in nature, each plant that grows in that soil and dies there leaves its organic matter behind, conditioning the soil ever more in a successionally more developed direction.
What is less commonly known is that there is a corresponding successional development of the microbial populations in the soil.
In the weed stage, all the soil harbours is bacteria, at best accompanied by bacterial feeding protozoans and nematodes. As organic matter builds up, fungi start taking hold and greatly improving the soil quality in terms of structure, air & water holding capacity, and nutrient cycling. Moving along the successional line, fungal presence keeps increasing.
So where we have a fungal to bacterial biomass ratio of 0.1 in that weedy field, we will have a ratio of 0.75-1 in our healthy veggie garden, a ratio of 2-5 and upwards in the root zones of our raspberries, currants.. and ratios of 100+ in healthy forest situations.
And along with these come ever increasing numbers and species of flagellates, amoebae, nematodes and microarthropods, who are essential to making the nutrients stored in the bodies of bacteria and fungi plant-available:
The bacteria and fungi mine nutrients from the soil (from mineral as well as organic matter) and store them in organic forms within their bodies, the predators then eat the bacteria and fungi and excrete nutrient excesses in plant-available form. And that will be happening mainly and most intensely in the plant's rhizosphere, because the plant is directing all this cycling underfoot by putting out exudates to attract and feed exactly the right types of microbes who will mine what they need at any point of their life cycle. About half of what a plant photosynthesizes goes straight into the production of these exudates, which can be very differently composed to feed different groups of microbes - even within the same root system.
It's mind-boggling when you think on it for any amount of time! We still know very little about these mechanisms, which has to do with research funding and interests of the money-givers. But it has been safely established that natural nutrient cycling is vitally dependent upon the cooperation of the soil food web with the plant, initiated and orchestrated by the plant itself.
What does need to be provided is the microbial herd itself, and we need to do this actively when working in closed systems as we do. And you are already doing that, by using your leaf mold and diverse composts, aerobically produced from well-balanced proportions of inputs!
But with every input you also have microbes piggybacking in, replenishing and developing your ecosystem. Now, conifers are way beyond cannabis successionally speaking, so will be bringing in sets of microbes that will less likely be put to use. They won't do harm, they won't even die, just go into a long dormancy, but it seems kind of a bit of wasted opportunity to me, as the sets found in deciduous plant matter will be much closer to home and more likely participate in the nutrient cycling feast underground.
I recently declared the only thing bark chips are good for is paving the way in people's minds for using the more wholesome wood chips lol
Firstly, they're hydrophobic. That's what they're meant to be, they're bark, protecting the tree from the elements! So they hold on to nothing, and also decompose very slowly just for being bark.
Coniferous bark takes it a step further, as it contains antifungal terpenes if not very well aged, and will slow decomposition yet more.
So unless we want to harness these properties for some reason (e.g. drainage, or in landscaping, "decoration"), it really isn't the ideal choice for woody additions in terms of soil production and nutrient cycling. And we
want good woody additions, as the complex organic molecules it's made up of is staple fungal food. And most of the time it's fungi we are missing in our soils.
Goodness grief, I've gone and written a book - again! Old habits die hard lol :smoking:
I do hope it all makes some sort of sense though!
Cheers!
