Big tree roots penetrate the ground for extended distances, sending out smaller feeder roots that have the ability to sense potential sources of nutrients. Sewer and septic lines give an ongoing and constant source of nutrients and water. When feeder roots detect this source through small cracks or drain holes, the lines may get clogged by development of new roots taking advantage of this food resource. Copper sulfate, sold in the form of blue crystals, which can kill the roots that clog lines without undermining the whole tree.
Treating Septic Lines
After the leak in septic lines becomes slow due to tree roots starting to grow in number, it is possible to care for the backed-up lines with copper sulfate. The roots will absorb the copper, but it is going to only spread a short distance to the main system. The localized copper toxicity will likely destroy the offending roots that then break down over the length of several weeks or days. To deal with septic systems, add copper sulfate to the distribution box in which the lateral lines connect. However, if there is not any access to this box from above, you can add two pounds of copper sulfate to a 300 gallon septic tank by flushing down the toilet, 1/2 cup at a time.
Treating Sewer Lines
Some nations, like California, don’t allow copper compounds for sewer root control since copper is not adequately eliminated in waste water treatment plants. Copper sulfate also corrodes the thin metals used in the plumbing of sinks and bathtubs. If tree roots are an issue in sewer lines, utilize physical removal of origins by a plumber, and root barriers. For serious recurring problems, consider removal of the trees.
Tree Root Growth
Tree roots grow the most during the fall and early winter when the above-ground region of the tree starts to go dormant. If roots are the cause of your plumbing problems, fall and early winter is when you should pay more focus on leak rates. Copper sulfate works best when you treat the problem early so the time it takes for the dead roots to decay and reopen the lines is as short as possible.
Permanent Septic Solutions
You may add small quantities of copper sulfate many times a year to prevent roots from discontinuing up septic lines so long as a single septic tank does not receive more than 4 pounds a year. However, feeder roots will continue to find the mineral supply if you don’t find a permanent solution. After removing the stoppage using copper sulfate, permanently block the origins using a barrier placed in the ground, like commercially available copper sulfate-soaked cloths.