I saw a sign today advertising “We level lawns. Organic soil.” Is there such a thing as inorganic soil? I thought this was utterly ridiculous. But maybe, just maybe, mind you, I am uninformed.
Probly, like “organic foods,” organic soil contains no more than some pre-agreed-upon amount of pesticides and/or herbicides. Then again, maybe it just distinguishes the stuff from packing peanuts.
There are indeed inorganic soils. ‘Soil’ as a term refers to the mineral material in the substrate, the organic matter, the water and the biotic factors and a few other things. The mineral material is usually comprised of weathred rock and is by definition inorganic and comprises the majority of most soils. Some soils such as recent volcanic ash and sand contain almost nothing but this inorganic material. The organic matter is largely decayed and decaying plant material, with a little animal matter and occasional other interesting things like coal. The biotic factors are bacteria, fungi, worms etc. So something like sand is an inorganic soil. The only organic soils I can imagine would be either from a compost heap, peat or very, very finely mulched plant material. It wouldn’t even technically be a soil then, since there is no inorganic component. It’s just mulch or compost. I can’t imagine for the life of me what you’d do with it since it would eventually decay into water and gas given emough time. But far be it from me to question.
Since they advertise that they “level lawns,” I would assume they are reassuring potential customers that the fill they bring in is clean, free of pesticides, herbicides and other contaminents.