drill some holes in it, and put in some mushroom plugs.
the fungi will help break it down.
i would use 2 or more species, you may have to research which is best.
you can add nitrogen on top also (urine works)
i had a couple of trees i had cut down in my yard.
it took over 5 years, but, it produced the best soil / growing medium i could have hoped for.
everything i planted there took off.
the decaying wood, and channels left by the roots
provided air and water pathways, habitat for worms, and lots of broken down material
I'm thinking as a long range project is there any tree that would grow super fast with minimal effort that i can do this with?
I'm thinking to convert a large area of poor soil say like an acre? Would this be the cheapest way to amend the soil? Grow the species for a few years then slowly start cutting down and planting a edible producing tree next to it. Eventually like in 10 years you have a whole orchard with much better soil. Or would this be a poor idea?
moringa would be a good choice.
i had a couple die on me, and the material is spongey
twigs will snap with 2 fingers. it breaks down very easily.
lots of nutrients as well.
i would use a few varieties though. maybe some nitrogen fixers.
locust comes to mind. Siberian pea... they wont break down as fast,
but you can chop+drop branches for mulch.
i think a cheap way to amend the soil
would be something like alfalfa
sunflowers should be fairly cheap for a pound of seed
and they are great for the soil, bring worms in...
as does mustard and radish.
google "cover crop" and mustard, or sunflower etc...
or, put it in youtube... lots of info there on cover crops.