Summer is finally here. In the Pacific Northwest, that means an extended period of hot, dry, sunny weather. While you are soaking up the rays, remember that newly planted trees need adequate moisture to establish new roots. A good rule of thumb is to water a new tree with five gallons of water for each caliper inch (the diameter of the tree trunk measured six inches above the ground), at least once a week during the dry months, for the first three years in its new location. But watch your trees for signs of stress. When temperatures rise above 80 degrees trees may need more water to support root and top growth, especially if you live in a windy part of the state.