Here's a spell that would have a huge environmental impact:
Charcoal (A)
Regular
This converts a cubic yard (1/5 cord) of wood into charcoal. This is about seven times as effective as charcoaling (
ref), which makes the elves and druids happy (well... less angry). It
is exhausting and takes a long time to cast, but still much much swifter than charcoaling the wood the traditional way.
This spell belongs to the Fire and Plant colleges.
Duration: Permanent.
Time to cast: Casting the spell takes 10 minutes, but the actual process takes 1 hour.
Cost: 10.
Too powerful?