If fire breaks out and catches in thorns so that the stacked grain or the standing grain or the field is consumed, he who started the fire shall make full restitution.
#exodus 22:6 #mishpatim

The key in dealing with accidental damages is restitution. The idea is not to punish someone for making a mistake, but to make it right. Punitive damages for negligence should be strictly limited regardless of the resources of the perpetrator.