National grid had to lay gas pipes through my garden, which is directly in the path of one cherry tree. They vacuumed earth around one main area near the tree, therefore, exposing roots. Will this in any way damage the tree if roots are exposed and, if not, for how long can they remain visible with no earth?
If it is a well established tree, some temporary root exposure will not hurt the tree much. If it is not too late, you can cover the roots with wet blankets to reduce damage. When they rebury the roots, give the tree some bone meal. This will help it regrow any roots that may have been damaged.