I like this, but I wonder about other nutrients plants need. Do we return those to the soil when we put charcoal back, or do we lose some when we make the charcoal? You wouldn't want to pump up fertilizer need during the process.
Are there other good uses for carbon that would help? Roadbeds? Construction materials? Media for hydroponics that, when clogged gets buried?
Shamefully, I'm confused by your question.
Any chance of re-phrasing it?
In much of the farm land devoted to growing animal feed (I.e., most of it) trees will happen through benign neglect. Simply ceasing the energy inputs (farming) will bring on the sequestering of carbon.
The problem is, how addicted are we to meat? Clearly, it is not required, and most authorities on the western diet and its problems suggest lower consumption of meat.
The hungrier half of the world is moving more aand more toward animal protein, which indeed, gives them and their babies a better chance for health.
However, the privledged western nations have since figured out a diet that would keep the poor healthy without needing to get into heavy meat consumption, with its related destruction of forested lands, and hard demands for water and energy.
Of course, their are wide swaths of land that aren't fit to grow trees or crops.
Wild herbivores do well in such marginal areas, in which case, hunting is appropriate.
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