With effort this yearI made about 100 gallons of charcoal from
tamarack wood. Pulverized the charcoal with a large mortar and
pestle. Spread the charcoal around 11 rose plants. I have a
Master's degree in chemistry and I agree the charcoal would hold
cations but I think (without proof) that bacteria living in the
charcoal pores would have a great effect on soil fertility. Too
early to make any assumptions but I believe charcoal works in
tropical soils but it is unclear about temperate soils.