# Best way to kill a plant/tree **URL:** \ **Category:** Factual Questions\ **Created:** [May 12, 2003, 12:25pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674 "2003-05-12T12:25:51Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 12:25pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/1 "2003-05-12T12:25:51Z")
In back of my mother-in-law’s house is a tree of some poison-ivy type variety with little poison plants growing all around it. From what I’m told they have tried dumping motor oil and other not so environmentally friendly substances on it without it dying or even even succeeding in keeping the little plants from growing back again. So far this tree has hospitalized two and sickened more. So Dopers, what’s the best way to kill plants/trees with extreme prejudice? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [May 12, 2003, 12:45pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/2 "2003-05-12T12:45:02Z")
Cut it down and feed it to a rented chipper. ---
**Author:** ![Daftbugger](https://avatars.discourse-cdn.com/v4/letter/d/9fc29f/32.png) [@Daftbugger](https://boards.straightdope.com/u/Daftbugger)\ **Post date:** [May 12, 2003, 12:46pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/3 "2003-05-12T12:46:08Z")
Cut entirely around the trunk with a knife ---
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 12:49pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/4 "2003-05-12T12:49:37Z")
Poison plant. Don’t really wanna have to get in there with a knife. Isn’t there something I can spray or dump on it? ---
**Author:** ![Aankh](https://avatars.discourse-cdn.com/v4/letter/a/ebca7d/32.png) [@Aankh](https://boards.straightdope.com/u/Aankh)\ **Post date:** [May 12, 2003, 12:51pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/5 "2003-05-12T12:51:16Z")
Giving it to [Maureen, Lissa, and co.](http://boards.straightdope.com/sdmb/showthread.php?s=&threadid=182755), apparently. 😛 ---
**Author:** ![Kamelion](https://avatars.discourse-cdn.com/v4/letter/k/8baadc/32.png) [@Kamelion](https://boards.straightdope.com/u/Kamelion)\ **Post date:** [May 12, 2003, 12:55pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/6 "2003-05-12T12:55:45Z")
… their ‘remedy’ for a sick-looking tree was to ‘prune it back so it will grow back healthier’. Their idea of ‘purning it back’ was to take off ALL THE BRANCHES THAT HAD LEAVES - cut back to about half the length of the branch. :smack: Quick Biology less for ya: PLANTS NEEDS LEAVES. More advanced lesson: TO PHOTOSYNTHESISE AND PRODUCE CHEMICAL ENERGY. That tree had no hope. Another effective method is ringbarking. Another quick Biology lesson; apologies if I’ve really made a mess of it, I’m afraid xylem and phloem are a weakness of mine. The method still works, anyway, even if the theory’s messed up. The bark of a tree contains xylem, a conductive tissue through which the water is transported about the plant. It MUST be uninterrupted to function. So, cut off a strip of bark ALL the way around thet tree so that the roots and leaves effectively have no contact. With the input (roots) and output (leaves) separated; the transpiration stream is messed up in a BAD way and the plant’s water transport ceases to function. And VOILA! Soon you will have a very thirsty and very dead tree. Non-tree plants are a bit more difficult, I’m afraid… ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [May 12, 2003, 1:05pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/7 "2003-05-12T13:05:01Z")
Buy a bottle of Round-Up at the local garden shop. Spray it all over the leaves. Spray on a calm day and do not spray it on anything else, it kills whatever vegetation you spray it on. Do not spray if rain is expected within 24 hours. I have used this as a last resort on tenacious weeds and it works wonders. It takes about a week before you see the plant dying off. P.S. The motor oil was really a stupid idea and probably illegal. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [May 12, 2003, 1:05pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/8 "2003-05-12T13:05:50Z")
It sounds as though the OP might have some kind of sumach tree or related; ring-barking will only work if you keep at it because the tree spreads by suckers which can pop up some distance away from the parent; it may even regrow if it is cut to the ground - although the plant needs leaves to live, it can recover using food stores in the roots. (although if you repeatedly cut it down it will eventually weaken and die) Treat the stumps with a proprietary stump killer to be sure… ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [May 12, 2003, 1:09pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/9 "2003-05-12T13:09:06Z")
Triox. Garden Centers and home centers carry it. Ortho product. Ivy type tree??? Give us a better descript of the plant in question. ---
**Author:** ![Aro](https://avatars.discourse-cdn.com/v4/letter/a/b3f665/32.png) [@Aro](https://boards.straightdope.com/u/Aro)\ **Post date:** [May 12, 2003, 1:10pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/10 "2003-05-12T13:10:58Z")
I’ve seen contactors on site kill beautiful sequoias by hammering a ring of copper nails around the truck and waiting until it rots. I have no idea as to the scientific validity of this method, but it seems to be an effective to kill off an unwanted tree. But this is really an underhand, stealth method of tree removal and takes a fair length of time to achieve the expected goal. ---
**Author:** ![Aro](https://avatars.discourse-cdn.com/v4/letter/a/b3f665/32.png) [@Aro](https://boards.straightdope.com/u/Aro)\ **Post date:** [May 12, 2003, 1:12pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/11 "2003-05-12T13:12:13Z")
truck should = tru **n** k ---
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 1:28pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/12 "2003-05-12T13:28:11Z")
> [@](#): > > _posted by CookingWithGas_ > **P.S. The motor oil was really a stupid idea and probably illegal** Probably, but after a few hospitalizations you tend to care more about family than a small contaminated spot in your back yard. > [@](#): > > _posted by Philster_ > **Ivy type tree??? Give us a better descript of the plant in question.** To tell the truth, I haven’t been close enough to get a good look at it. It’s only been pointed out to me. I can’t give much of a description other than its about 7’ tall. Is Triox for plants and tree’s or plants only? And will it permanetly destroy the root structure so it doesn’t decide to grow back again next year? ---
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 1:31pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/13 "2003-05-12T13:31:52Z")
That one sentence was supposed to be, "Is Triox for plants only or plants and trees? ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [May 12, 2003, 1:50pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/14 "2003-05-12T13:50:34Z")
> [@](#): > > \*Originally posted by CookingWithGas \* > The motor oil was really a stupid idea and probably illegal. It is definitely illegal and harmful for the environment and there is no excuse for doing something illegal and stupid. You might as well kill a virgin. If the plant is a problem go to the hardware store where they sell products for this purpose which (surprise) carry directions for use right on the label. And if you do not want to take care of it yourself in a responsible manner then hire the services of someone who will do it for you. ---
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 1:55pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/15 "2003-05-12T13:55:37Z")
What does killing a virgin have anything to do with anything? ---
**Author:** ![N9IWP](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/n9iwp/32/3154_2.png) [@N9IWP](https://boards.straightdope.com/u/N9IWP)\ **Post date:** [May 12, 2003, 2:26pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/16 "2003-05-12T14:26:18Z")
flame thrower? Seriously it it might be bet to hire sombody who already owns protective clothing. brian ---
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 2:52pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/17 "2003-05-12T14:52:25Z")
> [@](#): > > \*Originally posted by sailor \* > **It is definitely illegal and harmful for the environment and there is no excuse for doing something illegal and stupid** WELL, mister condescending, according to my state regulations [http://www.pacode.com/secure/data/025/chapter291/chap291toc.html](http://www.pacode.com/secure/data/025/chapter291/chap291toc.html) (please reference article 291.203) it doesn’t seem like the activity was illegal and I therefore ask you to cite the law or regulation that makes such an activity illegal. And I’d also ask to explain why it was stupid since it doesn’t seem to present any risk to the surrounding environment or anyones health. ---
**Author:** ![Philster](https://avatars.discourse-cdn.com/v4/letter/p/13edae/32.png) [@Philster](https://boards.straightdope.com/u/Philster)\ **Post date:** [May 12, 2003, 2:52pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/18 "2003-05-12T14:52:25Z")
Well, cut the sucker down! Then dig the roots up! Or, the removal of the bark will do it, but the roots of an ivy type plant will be back. Get busy cutting it down, and poison the roots (see local garden center for area specific products. Garden centers carry products very different from region to region and very different in danger levels). ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [May 12, 2003, 3:01pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/19 "2003-05-12T15:01:11Z")
Just curious… How in the heck did you get your username? ---
**Author:** ![Jdeforrest](https://avatars.discourse-cdn.com/v4/letter/j/49beb7/32.png) [@Jdeforrest](https://boards.straightdope.com/u/Jdeforrest)\ **Post date:** [May 12, 2003, 3:04pm UTC](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674/20 "2003-05-12T15:04:17Z")
> [@](#): > > \*Originally posted by sailor \* > **It is definitely illegal and harmful for the environment and there is no excuse for doing something illegal and stupid** WELL, mister condescending, according to my state regulations [http://www.pacode.com/secure/data/025/chapter291/chap291toc.html](http://www.pacode.com/secure/data/025/chapter291/chap291toc.html) (please reference article 291.203) it doesn’t seem like the activity was illegal and I therefore ask you to cite the law or regulation that makes such an activity illegal. And I’d also ask to explain why it was stupid since it doesn’t seem to present any risk to the surrounding environment or anyones health. [Next page](https://boards.straightdope.com/t/best-way-to-kill-a-plant-tree/174674.md?page=2)