Ken Peavey wrote:
Seems to me leaving them in makes for instant hugelkulture.
This is exactly what Masanobu Fukuoka was doing. He would plant fast growing trees and then chop them down after a certain height... just for hugelkulture. Let nature do most of the work!
Roots take decades to decay. You can drill holes in the stump to give funghi spores more space to attack. You can infect woody material with spores when you crumble already rotten wood in the holes.
About ten years rotted out all the roots and stumps. We've done clearing multiple times leaving the stumps in, flush cut to the ground. The stumps naturally become infected with mushrooms in a short period of time. Grazing animals help to mow down the regen which kills the roots since they can't get new energy.
Our experience is with aspen/poplar, maple, ash, spruce, fir and white pine.
Results may vary with climate.
We cut down a lot of diseased chestnut this winter and planted fruit trees between the roots. The regrowth helps to keep the area cooler and we use the whips to support plants. The new trees are doing well so far.
I wish more people would post photos, it helps a lot to see what people are doing.
Philip, I guess it depends on the size of your garden. I'm very lucky to have the space to work around root stumps but if I had a smaller garden I'd be tempted to pee on them too !