Although it takes longer than chemical herbicide, rock salt can effectively kill tree roots by robbing them of water.

Will table salt kill tree roots?

If you need to kill an entire stump, drill holes in the top of the stump as well. Fill the holes in the roots and stump with salt. Salt in any form can be used, whether it be standard table salt or rock salt. … The salt may make it difficult for plant life to grow in the area for the next several years.

How does salt kill plant roots?

1. Drill holes into the stump.
2. Pack the holes with rock salt.
3. After all of the holes are packed and the stump is covered in salt, pour soil and mulch over the stump.
4. Then, pour water over the mulch—this will dissolve the salt, help the roots absorb the solution, and pack the soil.