There is a table called "ItemImportMethod" which lists each Item and the method of which it came to exist in the database.
The ‘ImportMethod’ column can have the following values:
0 – Standard local object
1- External Object, e.g. item imported from xml.
2 – Originated from standard Replication
3 – Hierarchy managed item
When a hierarchy managed item is reset due to the node being removed from the hierarchy structure, the ‘ImportMethod’ column for the item is changed from 3 to 0.