Update from the olive grove: fire and insects (part two)

As if the drought, the fires, the variuos insect attacks were not enough, something unknown got noticed some time ago in one orchard. The weakest young trees were consistently loosing leaves from part of the branches, which in some cases were (are) completely essiccating.

At closest inspection, the reason for the above seemed to be those small scratches/holes:

You can see here another branch, showing the same pattern:

The bamboo sticks that were supporting the plants during their greenhouse stay looked even worst:

We still do not know who or what has made those piercings and whether it poses any major danger to the orchard. Some pieces of bamboo have been sent to the agronomy university and we hope they will be able to name the piercer. Our agronomist thinks it's a species of cicada and that the piercings are egg nests...

Just to be on the safe side, we removed the bamboo and cut off the pierced branches. We'll see...