So, no takers? Nobody want to tell me these trees are going to drop dead tomorrow? I was hoping for a realistic conversation about the real difference between organic and non-organic media, unlike the gobbledegook of the past. Looking at these pictures, one could safely assume that ultra high drainage is not the most important feature of media. There are other contributors to the health of trees, not the least of which is the biome that exists in good garden and/or top soils that doesn't exist in a media where rocks exceed some percentage I could not specify.
Since I am not scientifically trained, I can't articulate the facts, but they are something like this: There are populations of micro-organisms that need this or that combination of mineral constituents in soil. The more varied the minerals constituents, the more varied the populations. There are symbiotic relationships of myriad bacteria, fungi, et al that aid plants gathering resources and keeping the media healthy. If a media is made up of two kinds of rocks and a smattering of organic material it does not provide the wide platform of materials that good top soil does and is missing the biome that needs whatever other mineral compounds that are missing. Also, the size of the particle is important. Only the surface of the particle is available to be used by the biome. The amount of surface area available on one bonsai media rock is thousands of times smaller than the same volume of the mineral fraction of good top soil, and will support a concurrent thousands of times fewer micro-organisms. With a higher organic content which absorbs water by wicking it into its fibers and drys out slower than a free drop of water, a greater volume of the moist organic material can be in contact with a mineral surface making both more available to the biome.
Some of the biome works best in dry soils, some in wet soils. Populations wax & wane as the soil cycles through wet, dry, wet, dry, and the work gets done more or less continuously. If the media is on the dry side for a disproportionate percentage of the time, then the work that needs to be done in the wet period may not get done at all, or not as well as it should or is needed. This, in combination with the smaller, less varied population due to fewer mineral compounds being present makes for a much less efficient media providing less for the plant.
Oxygen is a gas. It permeates the soil and is hard to exclude. It can flow into soils from any surface, not just the bottom of a pot, and will do so as fast than the biome uses it. Nature abhors a vacuum and will fill it with air, immediately. Oxygen is present in water, even standing water. Lots of plants can live with wet feet and manage to get enough oxygen (see photos). The problem with standing water is that it holds the sulfur dioxide in solution which would ordinarily escape as a gas. It becomes a poisonous pool in a container.
There is no argument whether or not root rot kills plants. The question is where does rot root come from? Does it come from roots kept too wet (see photos), or is it the devolution of roots which are in an unhealthy media that does not support the biome that does its job when the media is at the wet end of the wet, dry, wet, dry cycle?
Attention Shallow Bastards of the World: Do not cite your anecdotal experience as an argument. There are thousands of media mixes being used by thousands of B'NUT users which proves only that almost any mix can be used successfully by someone, someplace, sometime. Cite facts. If you are like me and scientifically challenged, get as close as you can to facts and admit it so your offering can be useful in its context.
So B'NUTers, what say you?