[danieltillett]

You can't just bury trees whole, you need to convert the cellulose and lignin into charcoal so the microbes in the soil can't break down the carbon (coverting wood to charcoal basically scrambles the carbon bond structure preventing the easy enzymatic cleavage of the cellulose polymers).

A few people have suggested doing exactly this with nitrogen fixing trees like Casuarina sp.

[ianai]

I’m not sold on having to make them charcoal. My thinking is they are essentially rejoining a natural cycle at that point. And probably a portion may be sold for consumer products. The carbon needs to be out of the air, yes. But it doesn’t have to be locked underground to be out of the air.