Update: I gave a young oak a deep root soak instead of surface watering
I did it for a client's tree in Boise last fall, thinking it would help with drought stress. The next spring, it put on almost double the new growth compared to the same species nearby. Anyone else seen results this strong from switching watering methods?
Had the same problem with some shrubs last season, Amy. Switched to a slow, deep soak at the roots twice a week instead of a daily sprinkle. The difference was huge, the plants just looked stronger and held up better in the heat. It takes a bit more time to set up, but you save water and get better results.