I have been doing more research and I found the issue but I am not sure how to fix it.
I dynamically load the tree when nodes are opened. I have added a search capability which automatically opens the tree for the user based upon the item they picked in a RadAutoComplete box. The tree opens fine but the item is not selected. I open the tree in the RadAutoCompleteBox's selectionChanged event. I load the ViewModel items the user picked and set IsExpanded to true. The GUI does not draw the tree opening until the selectionChanged event finishes. After creating the ViewModel objects I set the tree's SelectedItem in the RadAutoCompleteBox selectionChanged and it appears that it does not apply since the tree has not opened yet.
If I manually open the tree, use the AutoComplete to search for a node and select it, the node is selected and the tree's SelectionChanged fires.
loop through ViewModel creating new objects and setting their IsExpanded to true
When the loop is done set the tree.SelectedItem = the object the user selected
End of SelectionChanged
It appears that I need to set SelectedItem after the tree has opened all of the nodes. Any opinion on a better way to do this?