Birch plate. Beware of termites.
The item id for Plate Large Birch Equilateral in unturned is 1144. You can use this ID with the commands below to spawn the item, give it to a player or buy it on a modded economy server.
Useable: Barricade
Build: Freeform
Size_X: 2
Size_Y: 2
Size_Z: 0.325
Health: 300
Range: 8
Radius: 0.5
Offset: 1.875
Explosion: 28
Blueprints: 2
Blueprint_0_Type: Barricade
Blueprint_0_Supplies: 1
Blueprint_0_Supply_0_ID: 37
Blueprint_0_Supply_0_Amount: 4
Blueprint_0_Build: 27
Blueprint_1_Type: Barricade
Blueprint_1_Supplies: 1
Blueprint_1_Supply_0_ID: 1150
Blueprint_1_Supply_0_Amount: 4
Blueprint_1_Build: 27
PlacementAudioClip: Sounds/WoodenPlacement.mp3
Has_Clip_Prefab: false