Stefanos, what terrible news. Your trees! Like you asked how does that happen to something that has been thriving for thousands of years in the same area. A little bit different, and a little the same this year there have been MANY Saguaros that have died here in the desert. They are only hundreds of hears old, still that is so fascinating to me that after hundreds of year this would be the year they died. We had an extremely hot summer and the lady at the Desert Botanical Garden said that the summer before was hot too and the temperatures didn't cool down at night, too much stress.
Wow, if even cactus are dying from the heat we are in trouble! Sorry to hear that. The olive trees will recover, they have done it in the past and I trust that they are very resilient but I don't expect much of a harvest for one or two more years. That is of course if the weather pattern doesn't deteriorate and this kind of drought and heat remains a rare event that happens seldom.