It’s likely that the reason your trees died from drought is that someone many years ago planted a variety that is not native to your region, thinking they would water it regularly, then they moved away and someone came who didn’t know it needed supplemental watering beyond rain. Plus, as a landscape designer for ten years, I know that every tree species has a finite lifespan, some longer, some shorter. Unfortunately, the crews I worked with cut down thousands of trees, because they were the right type, planted in the wrong place or at the end of their natural existence. Tree maintenance is one of the most expensive home improvement costs, because it is such a dangerous and equipment-intensive profession (tree companies have to carry extensive liability insurance with huge premiums). Everything else in your article is spot on.