Some time after the Civil War started the Stormcloaks tried to burn down the mill, but they were discovered and stopped in time.
Hjorunn will buy any Firewood the Dragonborn has chopped at the nearby block for full price.
If The Elder Scrolls V: Hearthfire is installed, the Dragonborn can purchase Sawn Logs from Kharag gro-Shurkul at a rate of 20 logs for 200 ; however, he won't let the Dragonborn cut any Sawn Logs, but it is unknown if that can change.
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