Air spading uses high pressure air with a handheld spade (like an air gun) to expose roots systems without harm. It uses high pressure air to expose the root system, so the roots can be pruned before any excavation occurs. This helps minimize damage to the tree roots because they are properly pruned, limiting the number of roots that are exposed during excavation and preventing further damage that can lead back to the trunk of the tree. It is extremely important to consider the roots of a tree underneath the ground as this is what keeps the tree stable and healthy. It is a common myth that tree roots grow deep although its uncommon for trees to have roots deeper than about 2m (most roots are found close to the soil surface, with 90% or more of all roots located within 60cm of the ground surface). Tree roots can extend to 5m or more from the trunk of the tree. In general, the rule of thumb is that is a tree should not sustain more than 25% root loss during construction.