Question
We had major problems woth sewar line floods, at least twice a year, because of the roots in out pipes.
We cut down the trr - is it possible that the roos are still grwoyng - as we continue to have blocked sewer lines, with roots ???

Answer
I would use a herbicide in the pipes to kill the roots and then if the trres sprout use Roundup to kill the sprouts.



The roots of trees extent out about 1 1/2 times the width of the foliage and the roots at this point are smaller and usually the ones entering the pipes.  Older sewer lines are made from clay type pipes in sections and these have openings at the joints where roots can enter. The newer plastic pipes do not have this problem. One of the ways to stop the roots is replace the pipes but this is quite expensive. There are chemicals that can be flushed down the toilet that will kill the roots in the lines.

The destruction of root hair growth in pipes can be accomplished by mechanical removal. Mechanical removal of the root ball blockage does not prevent the recurrence of new growth. In contrast, chemical technology, which is primarily based on herbicides, has advanced to the point where either in combination with mechanical removal or by chemical means alone, the root mass can be removed and future growth retarded or eliminated. Continued application of the appropriate chemical will degrade any remaining root masses, destroy root hairs remaining in the pipe and effectively eliminate future root growth in the pipe. A note of caution, the timing involved in the combined use of cutting tools and a chemical is critical. Cutting removes the roots and root hairs through which the chemicals are absorbed. After cutting roots will secrete a fluid, which hardens and covers the cuts caused by the mechanical process. This hardened fluid and the absence of root hairs removes any pathway through which the chemicals can penetrate the root system in the pipe. To use the combination of a mechanical and chemical approach, the chemical should be applied immediately after the root mass is cut or wait a period of 3-6 weeks, at which time sufficient new root hairs will have emerged to provide a pathway for the chemical. If only a chemical approach is utilized, the initial application will destroy the root hairs and begin the process of degrading the remaining root mass. The degradation process may take weeks depending on the nature and size of the root system. It is also important to begin the treatment as part of a preventive process, whereby the treatment process begins prior to blockage, i.e. typically in spring and in the fall. The chemicals employed are non-systemic herbicides, therefore present no danger to the tree system as a whole.

Copper sulfate is the most common herbicide used by the homeowner and is an EPA registered product. The copper sulfate is applied by flushing a significant quantity, usually 2 to 4 lbs., into the drain line through the toilet that is closest to the discharge line or through the discharge line clean-out plug. Drain waste discharge lines are usually partially filled with water and the root hairs and root balls are commonly in contact with that water. Once flushed through the toilet, some of the copper sulfate dissolves and is taken up by the root hairs, while the larger crystals become enmeshed in the root mass and provide a longer lasting treatment effect. The copper sulfate should be applied during periods of low water volume flow in order not to prematurely flush away the product or dilute its concentration. The copper sulfate will kill the root hairs upon contact and overtime the larger root ball. Copper sulfate will not remove mechanical obstructions, grease or other matter not related to the root system.

Dichlobenil is an aquatic herbicide approved by the EPA that kills root systems within an hour of contact. Dichlobenil has been used to control aquatic weeds for many years and due to its low water solubility has little effect on microbes or bacteria. Dichlobenil has also been packaged with a variety of foaming agents and surfactants in order to increase the absorption efficiency of the dichlobenil by the root system. These agents include sulfamic acid, whose alkali derivatives have been identified as being poisonous to woody plants and surfactants, which help the herbicides cling to and penetrate the root hair system. Dichlobenil systems are available through professional sewer maintenance personnel or through common retail outlets. One of these is called RootX. Here is a web link to RootX information. http://www.pipedoctorusa.com/RootX_Application_Notes_and_Directions.html