I enjoyed my long weekend in Pittsburgh for Thanksgiving. Very few photos were taken, though I do have a couple:
When I got back to State College yesterday I spent some time in the lab weighing firs, went to a PSCG meeting, and went grocery shopping. Today I scanned roots, weighed firs, and started gathering information about analyzing all my root scans.
My junior rhizotron experiment is finally starting to show some losses due to phytophthora. The disease has been slow developing due to the season. This is a combination of two images I collected today:
It is difficult to see detail. The needles on this fir are gray-ish green and completely dried out. All the roots are discolored. Plants that have no foliar symptoms have light colored, healthy roots. It’s a nice sight. It shows me that in this situation the isolate of P. cactorum I have is more virulent than the P. drechsleri isolate. I’m hoping this conclusion becomes even clearer over the next week or two.