Biochar trench method works well.

Hi,

I just wanted to dutifully report that I burned some brush in a trench the other day to see how that method of biochar production worked. I was impressed.

I usually just burn large piles of brush, mostly because I don't have a lot of spare time and I do have a lot of dead, dying or just congested plant matter around my property. By adding it to the top of the pile every time the flames died down I was able to create TONS of char this way.

But finally I got around to digging a small trench (now that I know it works I'll make it 2x as long and 1.5x as wide) and burning the slash in the pit. Same method as before, add new wood as the flames die down from the last batch. One small pile, say 8 feet in diameter and 4 high produced 15 gallons of prime charcoal. It's hard to gauge how much  plant matter was there, especially in gallons, before burning but it looks like almost none of it turned to ash! Incredible.

Cons: Digging a stupid hole, having to either dig another stupid hole or drag brush long distances for each new cleared area. Also, having to trim the brush to fit in the trench kinda sucks.

Credit to the Skillcult guy on YouTube for the inspiration. Thanks!

Thanks for sharing, I have been wanting to give biochar a try, sounds like a good way to get into it! How deep did you dig the hole?

I dug it about 2 feet deep which seemed about right. This width of about 2 feet worked fine but I since I was burning mostly black oak and manzanita branches I spent too much effort shaping the branches to fit in the hole. The manzanita especially doesn't want to bend into the hole. I plan to expand the trench to: 7' long x 3' wide and keep it 2' deep.