How is the Portfolio Tree related to the Project Tree?
This article explains how the Portfolio Tree is related to the Project Tree.
Answer
The Portfolio Tree uses the selection in the project navigator to set the initial default scope or project of the portfolio items to display.
Displayed portfolio items include all portfolio items and children, regardless of where the child items sit in the Project Tree (provided the user has permission to view child items). So, if a portion of the features or backlog under a portfolio item is farmed out to another organization, that feature or backlog will still be visible under the parent portfolio item in the Portfolio Tree.
Default rollup values for Estimate and Progress are, likewise, inclusive of all lower level work regardless of project. To specifically view rollups that include only items in the currently selected project scope, customize your view to show the 'Scoped' columns for Estimate and Progress.
Cross-Project View Example
For example, using the setup below, when a user in the Team 3 project views the Portfolio list, it includes the Cross Team Feature - Team 3 Sub-Feature portfolio item and both stories below it even though the story in Team 4 falls outside of the selected project scope. Likewise, the Estimate total for Cross Team Feature - Team 3 Sub-Feature includes the points for the stray story in the Team 4 project.