The Property Tree Browse window shows the properties that have been defined in a hierarchical fashion. The hierarchy tree shows the top level properties, below them are level two properties, and so on. The Property Tree Browse window also shows any assets that have been linked to the properties, at the appropriate levels.
If an item has a plus sign (+) then there are more items below it in the hierarchy. You can click on the plus sign to expand the next level in the hierarchy. When a level in the tree is expanded, the plus sign will change to a minus (-) sign. If you click on the minus sign, the level will be collapsed.
If an item does not have a plus sign next to it, then there are no more locations or assets below it in the hierarchy.
This window is a visual representation of the property hierarchy. It allows you to see how your locations fit together in the overall scheme of properties.