Rich Grise fired this volley in
news

I've always thought it would be fun to burn out a stump with oxygen -
ordinary welding oxygen, with about 6' of 1/4" or so stainless steel
tube; start a little fire on top of the stump, and blow O2 on it.
Would that work?

It'll work.

Let's say the stump weighs 150lb. About half that is carbon. Let's
delete the moisture, and say 60lb. It takes 32/14 oxygen to burn carbon.
So it'll take about 137lb of oxygen to burn 60lb of carbon (not counting
losses and H20 from the hydrogen in cellulose). A more reasonable figure
for burning wood would be 200lb oxygen per 150lb stump.

There's about 13.38 pounds of oxygen per 150cu.ft. cylinder, so it'll
take 15 full 150cu.ft. cylinders to burn a 150lb stump to the ground.

Good luck!

LLoyd