Thank you so much for all the info!!!! You had me at helping break up clay soil! Gotta try this. I realize I'm a dinosaur, don't have cell phones and have a terrible time trying to find info on the internet ( theres just so much I get overwhelmed and confused). What I'm saying is I would never have been able to find all this on my own, and I'm so grateful to you for taking the time to write all that out and for being so nice about it. Bless youYou can find a lot of good info on biochar online, but the basics is that it's a carbon source with a very high surface area. That makes it great at retaining nutrients and water, and adding carbon to your soil (which can help break up clay soil and provide a better growing medium).
Wood ash also has it's uses in the garden, especially if you have acidic soil like we do up here in the northeast. Ash adds trace minerals and lowers PH, while biochar adds carbon and surface area. Very complementary.
Speaking of complementary, adding biochar to your compost makes both a bit better. The biochar absorbs nutrients (some call this "inoculated") that otherwise might leach away or cause odors. When added to your garden, the biochar slowly releases the nutrients, helps retain water, etc.
From a sustainability standpoint, one ton of biochar sequesters roughly 3 tons of CO2 in the soil, potentially for a long period of time. So, it's a great tool for reducing your carbon footprint and putting that carbon where it belongs...in the soil.
I use biochar in my coop bedding to absorb excess nitrogen (reduces odors and healthier for the chickens). The bedding (with biochar) then goes into the compost. Once the compost is ready, it goes into whatever planting project I have. "Stacking functions", if you will.