It is unlikely that trees growing near the construction site of a new hope of other structures will escape the event unscathed. When all the equipment is gone the trees should be inspected for damage and treated. Landscape trees add value to the property, so spending some money on their future health is warranted. The two primary types of damage are wounds to the trunk or crown, and soil changes that are detrimental to the root system.
Trunk and crown injuries are usually obvious. Branches that are split, torn, or broken should be removed. Also remove any dead, diseased or rubbing limbs from the crown of the tree. It may be necessary to remove some lower limbs to raise the canopy to provide clearance around the new structure.
If the trunk has damage, remove any loose bark and cut away any jagged edges with a sharp knife. Take care not to cut into the lighter colored living tissue. Wound dressings are not recommended, as they have not been proven to be beneficial to tree.
Soil related problems include compaction from equipment use and changes in soil depth through grading and fill material. Both cause a depletion of the oxygen supply to tree roots and can cause a tree to decline rapidly. Soil aeration can help, and the most common method involves drilling holes in the ground. The holes are 2-4 inches in diameter and made about 3 feet on center throughout the root zone of the tree. The depth should be at least 12 inches, but may need to be deeper if the soil grade has been raised. Sometimes the holes are filled with peat moss, topsoil, or some other material that maintains aeration and supports root growth. This is called vertical mulching.
A recently researched aeration method that shows promise is radial aeration. Narrow trenches are dug in a radial pattern throughout the root zone. The trenches appear similar to the spokes of a wagon wheel. The trenches should begin 4-8 feet from the trunk of the tree to avoid cutting any major support roots. They should extend at least as far as the drip line of the tree. For soil compaction the trenches should be about 1 foot deep. If the soil grade has been raised, they need to be deeper. The trenches can be backfilled with topsoil or mulch.
A good arborist can assist you with deciding on the best treatment for your trees, and can be well worth the money. Trees can add 20% to the value of your property, so consider it a real estate investment.