Trenches for irrigation or electricity should be routed around the protected root zones of important trees. If placing a trench near trees is unavoidable, dig through the protected root zone by hand. When roots more than inch in diameter are encountered, tunnel under them to avoid damage. Adding or removing soil within the protected root zone should be avoided. Adding fill causes soil compaction and changes the site's drainage.
Soil compaction suffocates roots and can eventually kill the tree.
Established trees require supplemental watering during dry periods. The best way to determine if a tree needs water is by looking at the foliage and feeling the soil. When leaves on deciduous trees begin to droop, it's time to water. When squeezing a handful of this soil, it will pack together but can still break apart easily. Soil that's too dry will crumble when squeezed.