Mulch is invaluable for tree health and care because it insulates the soil, and provides a buffer from hot and cold temperatures. Mulch retains water to help keep roots moist. Additionally, it keeps weeds out to help prevent root competition.Mulch retains water which helps to conserve moisture needed by the tree's rootsystem. Mulch also assists in weed control. By reducing weeds, whihc is a huge competitor for moisture, more moisture is available to the tree's root system allowing trhe tree to live and grow with minimal stress from lack of water.