Oh, it was just the white thorn bushes right at that corner of trail that had completely overgrown the trail. Couldn't even see the cut logs, or really any logs for that matter, that usually help me indicate where the trail was. I knew roughly where I was, just wasn't sure which drainage to go up and didn't really want to backtrack through all the white thorn if I picked the wrong one. I was there July 11, 2008 so sometime around the time you must have been there.
Haven't made it up that section of the Old Tioga Rd, but I would think fire would help clear up the area, provided it is not a 'catastrophic' fire. Clears out the underbrush and smaller trees, the bigger trees survive and have more room to grow. I thought that fires in general are healthy for a forest. But I don't know enough about fire to say authoritatively if it would be good for that area.