We looked more closely at the fir tree near 1007 Cloverlea. The needles are green above with the silver or white stripes below. Considering the new Maryland guide to conifers, this may be a Fraser Fir. The twigs and the bark are approximately right.
The needles and flat and do not roll between your fingers. Removing the needles shows small circular divots in the twig. Tips of the needles are blunt to indented.