There is a very large pine tree near our house. Yes, adding soil to the top of existing roots is a problem. It often injures or kills trees by decreasing the oxygen supply to the roots.
Inadequate oxygen interferes with metabolic processes and root growth.
Once root growth slows down, the supply of water and minerals to the tree is diminished. Lack of root growth and consequent decreases in water uptake lead to water stress in the shoots, thereby reducing photosynthesis but increasing respiration. Decreased nitrification and eventual loss of nitrogen to the tree reduce vigor and growth and may eventually kill it. McKenzie The information given herein is supplied with the understanding that no discrimination is intended and no endorsement by the Purdue University Cooperative Extension Service is implied. Any person using products listed assumes full responsibility for their use in accordance with current direction of the manufacturer.