Produces tree trunks out of 2 unprocessed wood. Necessary to make ammo for arrow towers.
- You should keep these 2-3 levels lower than your base.
- Only upgrade them if you see your supply is full but need more ammo.
- Keeping them the same level as your other industry helps keep ratios filled.
- These are a low priority for upgrading. Only upgraded if needed.
- Keep them 1-2 levels higher than your Harvesters.
- don't forget to upgrade steel factories to the same level, to keep arrow production steady.
Characteristics at different levels
 original reference