Ky property is wooded, mixed hardwood and softwood and this is how I to it....
When I cut them down, I leave about 12" proud of the ground.
Then I drill 1/2" holes all the way around in the cambium layer (just below the bark but not into the inside wood. I fill the holes with straight glyphosate (Roundup) and I drill 1" diameter holes down into the stump about 12" deep (with a ship auger) and then drill intersecting holes in from the sides. I fill the vertical holes with epsom salts.
Let them sit in the weather for a month or two (the stump will start to decompose and turn gray.
When it turns gray, I bore some more 1" holes straight down about 12" and fill with diesel fuel and let it soak in, I do that a couple times.
Then I place a 55 gallon drum (with both ends cut off (as a chimney), place it over the stump and cover the top with match light charcoal briquetts and light it up.
Takes about a week but I've had 100% success in burning them out. After it gets going good and burns up the diesel, it makes a pretty good BBQ fire.
The Glyo kills all the roots and what is left is a hole with ashes. Cover it up and call it good.
Like I said, I've had 100% success so far.
The only limit I have is the drum diameter. I do rake a hole saw and drill a few holes around the base of the barrel to act as a draft source. I don't use a leaf blower or anything, I just let it roast itself. The trick is to let the diesel soak in real well. if you get in a hurry, the stump won't burn all the way down.