There are several large surface roots around my maple tree. Can I safely cover these roots with soil?

FAQ
Question: 

There are several large surface roots around my maple tree. Can I safely cover these roots with soil?

Answer: 

Trees have shallow roots. The vast majority of a tree’s roots are located in the top 12 to 18 inches of soil.  As the tree roots grow, some of the larger roots near the soil surface may emerge from the ground. While many individuals regard surface roots as unwelcome, they are normal for many trees. 

It’s usually best to ignore surface roots as much as possible. (Granted, mowing around surface roots can be tricky.) Covering the area around the tree with 1 to 2 inches of soil provides only temporary relief. The tree roots will continue to grow and will probably reappear in a few years. Placing 4 or more inches of soil around a tree may damage or destroy it by depriving some of the tree’s roots of oxygen. 

If you’re not fond of mowing around the tree roots, you could destroy the turf and apply mulch around the tree. Wood chip or shredded bark mulches are actually beneficial to trees. An appropriate mulch depth for areas around trees is 2 to 4 inches.  Shade tolerant perennials, such as hostas, ferns, woodland phox, wild ginger, and barrenwort could also be planted around the tree.