Autumn Blaze exposed roots
The tree is 18 years old and in recent years more roots have been exposed above ground making mowing difficult. Can I cover the root with several inches of soil and plant new grass seed without harming the tree?
Rice County Minnesota tree roots
As long as you have this tree you will have surface roots and cutting them will not only rob the tree of water/nutrients but expose it to possible infection. Rather plant a ground cover between the roots and mulch lightly over the area. For more information see http://www.extension.umn.edu/garden/landscaping/implement/planting.html merely covering them with soil will deprive them of oxygen plus the roots will try to raise more.