How do you handle a station that is both a source and a destination for a resource?

I have a large station with a forest on one end and a sawmill on the other. Wood is piling up in the station; does any portion of it get consumed directly by the sawmill? What do I need to do to get the rest of it consumed as well (preferably by the same sawmill)?

Solution 1:

This station is exactly like a passenger station that both generates and accepts passengers:

• the wood that is being generated there needs to be taken to another station that accepts wood.
• the station will accept wood from other sources, but never from itself.

None of the cargo is "absorbed" by the local sawmill - you will need to transport all of it away, and if you want that local sawmill to generate goods you will need to transport wood in from another source.

Solution 2:

it won't be consumed, a station can either be a source or consumer, but not both. What you have to do is create a separate station, preferably that only covers the sawmill, and transfer between those two.

If you can't, you'll have to specify which station to load/unload at as shown in this answer