Minecraft wiki entry for Configured_feature, associated text: block_column
 direction: The direction of the column. One of up, down, north, east, south, or west.
 allowed_placement: A block predicate.
Block predicate[show]
 prioritize_tip: Determines where to cut off blocks when space is restricted. If true, will start removing layers from the start of the column.
 layers: The layers.
 height: Int provider specifying the height of the layer.
Int provider[show]
 provider: The block to use for this layer.
Block state provider[show]