Assembly: Microsoft.SharePoint.Taxonomy (in Microsoft.SharePoint.Taxonomy.dll)
If this property is true and the TermSet is open, then typing text in the taxonomy field editor control will display a Create New option in the Suggestions drop-down list if that Term does not already exist at the root level of the TermSet. Selecting the Create New option will create a new Term with that text as the default Label object.
This property does not apply to the the Enterprise Keywords TermSet, since it always allows new Term objects to be added by selecting Create New in the Suggestions drop-down list.
It is not possible to create Term objects that are created by using the Create New at an arbitrary position in the hierarchy of Term objects in the TermSet. All Term objects created with this option are created at the root level of the TermSet.