Decor and furniture
Sign Decal Wood 8x4
It's a sign. You write things on it.
Harvest drops
Wood× 2
Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.
When it collapses
Falling, it leaves 
Wood Debris (Terrain) (75% of the time) where it lands.
Where to find (4 POIs)
Dr. Karen Higashi Residence (tier 5), Navezgane High School (tier 4), The Bear Den (tier 3), Deracinated Domicile (tier 1).
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.