Tree Root Killer

Tree Root Killer
Often, clogged sewer systems are caused by tree roots. Aggressive roots have a tendency to completely destroy the sewer system, and therefore, it is necessary to have a handy tree root killer in case it is needed to be used.
Gardenerdy Staff
Last Updated: Feb 9, 2018
Man cuts a tree.
There are many kinds of tree root killers available in the market, but while choosing one, care must be taken keeping different aspects in mind. This is because, almost all the available products are chemical-based, and wrong usage may lead to disastrous consequences. Since the tree root effects on soil can be long-lasting, good care of the soil must be taken too. Always read the instructions mentioned on the box cover of the root killer carefully before using. Traditional methods can also kill the tree roots, but you need to have patience for that. Ultimately, you have to remove the tree roots physically, but it helps a great deal if they are dead.
Types of Root Killers
Roundup: Roundup is a chemical root killer for trees which has been the most popular root killer in terms of sales, since 1980. The main ingredient of Roundup is glyphosate isopropylamine salt. Once Roundup is applied on a tree stump (as per instructions), the leaves start yellowing within 48 hours. Roundup systematically kills the plant from inside.
RootX: The main ingredient of RootX is aquatic herbicide dichlobenil. Although, RootX is chemical in nature, it does not harm your pipes or septic tanks or any kind of drainage system. RootX is the main competitor to Roundup. It is highly effective and safe to use too.
K-77 Root Killer: K-77 is very effective in killing roots within a week or so. And the best part about it, is that it does this without affecting the surrounding trees or ground in any way. A point to note is that, make sure your drainage isn't completely blocked and stagnant. There should be some amount of flow for K-77 to have the desired effect.
Copper Sulfate: Before the advent of Roundup and RootX, copper sulfate was used to clean all pipelines. Although copper sulfate was very effective in unclogging the pipes and killing the tree roots, it had many costly side effects. Copper sulfate being acidic in nature, reacted with the pipes and steadily eroded them. It killed the bacteria in the septic sewer system as well. The eroded pipes would eventually crack and leak the chemicals which were inside. Modern-day plastic pipes do have tolerance to copper sulfate, but the bacteria does not, so usage of copper sulfate is not advised.
Nitrogen Fertilizer Liquid: Yeah I know, it's a contradiction. Nitrogen is a fertilizer, not a tree root killer right? The usage of this fertilizer is quite peculiar, as described below:
  • Drill 10 to 15 holes in the tree stump. They should be about 10" deep.
  • Now pour the nitrogen fertilizer liquid into these holes.
  • The nitrogen fertilizer (which is responsible for tree growth when mixed with soil), starts eroding the tree stump from inside.
This process is slow and not reliable. If a sewer system is completely clogged by tree roots, the use of a nitrogen fertilizer to unclog it is not advisable.
Tips on Using Tree Root Killers
  • Treat the entire stump. If holes are being drilled, make sure the drilling is done all around the edges of the stump.
  • The best time to use root killers is autumn and winter. As much as possible, avoid doing this in summer or spring.
  • It is a good idea to cover a cut stump with plastic, so that it secures the stump and keeps off rain and other elements which may encourage sprouting.
  • Always wear protective clothing while using root killers.
  • Keep children and pets away from the location.
Some Home Remedies for Killing Roots
Salt: Simple plain old salt will do the trick. Make a highly concentrated saline solution, and pour it in the soil around the tree stump. You have to do this at least five times a day, until all the tree roots are dead. According to soil science, by using salt, you are rendering the area completely barren.
Asafoetida: It is a traditional Indian, low-cost, easy-to-use, and time-consuming root killer. But generations and generations of farmers have proved this method of tree root killing to be extremely effective. You have to stuff the tree stump with bits of asafoetida, as much as you can, and as many times as you can. Drill holes and stuff it with asafoetida. You'll find asafoetida at any convenience store. Asafoetida takes a minimum of two weeks or even more to kill the tree roots. It also maintains the soil texture, and does not have any side effects (except of course on the tree stump).
Caustic Soda: Make a solution of caustic soda and water (one part caustic soda and two parts water), and apply this solution three to four times on the stump. Gradually, it'll kill the stump, and then go on to kill the roots as well. But the roots may need to be physically removed.
Compost Piled on Tree Stump: Cut the tree in such a way that its stump is at ground level. Make a big pile of compost on the tree stump. The chemical substances from the compost helps kill the stump and eventually the roots as well. But composting should be done only if you are not in a hurry.
Baking Soda and Vinegar: Apply a thick coat of baking soda on the roots and pour about a gallon of vinegar on the stump. Do not get alarmed by the fizz. It's an effect of the chemical reaction. This mixture is also an effective root killer.
All the above mentioned tree root killers should be handled with care, and the proper instructions should be followed, so you can have an event-free process to kill tree roots. Always use rubber gloves while handling a chemical based tree root killer. I hope the above mentioned methods help in getting rid of the tree roots out of their land and sewage system.