Tree will lose moisture by transpiration through the leaves. The porse of the leaves will release moisture during the photosynthesis process. The tree will try to clse its pores to try to conserve moisture but it is impossible to stop the lose completely in high temperatures. The best thing to do for all your trees and shurbs is to water them. The water of shurbs is fairly easy as most of us do that already but to water a tree can be a little more challenging. In order to water your tree just apply a hose with a sprinkler attacment and allow it to water the entire root system. (Note: the root system extends a min. of the enitre canopy of the tree.) About a half an hour in multiple spots will be a good average time to keep your tree watered. If the temperature are high and conditions are dry this should be done daily if possible. Please note less water will be needed on smaller or newly planted trees.