Especially if that root in the fourth shot is from a pine not an oak.

The brown flocks on the edge of the thick, persistent annulus along with whitish cap fibrils that age into dark scales, caespitose growth. At least some of the basidia should have clamps at the base. Here is a link to a key in Mycotaxon (1987) to five species of Armillaria that I have been using along with the Volk web site. http://www.cybertruffle.org.uk/cyberliber/59575/0030/0102.htm