In reply to Mr Humphrey Carter’s sad story of his dog, I would like to try and help, maybe explain a possible cause.
I live on Majorca part of the year, and have seen these cones in the trees before.
Most of the time they are put up the in the trees at this time of year, to attract the Arugas (caterpillars) these are very poisonous, and can kill in certain circumstances.
The rash Mr Humphrey mentions, is from the hairs of the caterpillars, if touched. People should be very aware of these insects, and they can be identified by the way they follow each other in a line (Pine procession caterpillars )
All residents should look online about them.