Poison ivy : copper and sulfur for knockback?


I have a huuuuuuge patch of PI that i gotta destroy. Makes me ER visit ill.
It laughed at roundup. A jabba the hutt kinda laugh. Salt/vinegar/soap HAHAAAA. Yeah right.

Im going to smother it, but wondered if anyone tried a nasty strong tank mix of copper and sulfur to the leaves to burn them prior to wading in (in full bunny suit) to lay the cardboard and heavy landscape fabric down


Triclopyr 4E



PI will not laugh at Roundup, if you make it twice stronger that it should be. Buy concentrate and mix yourself. Spray till point of run off, try to cover all leaves. In few days come back - spray what is not wilted. Do it for couple weeks. They will die eventually. Now the tough part. You will need to somehow remove that dry PI material(they are still poisonous, DO NOT BURN!!!) and PLANT something on the spot. PI is earth bandage, it will fill in empty spots. The easiest way would be cover whole thing with a planter, or lay heavy landscaping fabric and bring some soil to place on top and plant something. If you brave enough to remove it, leave it till fall covered with cardboard, it is easier to remove when it is cool - you will need full body protection - I used rubber boots, heavy pants and washable jacket , heavy rubber gloves. Make sure you do not wipe sweat while you working there… Bag the derbies from top of the soil in trash bags. When soil is clean, dig the rest of the roots with the same precaution. After you done, ask somebody wearing gloves to help you to undress and place the close in the washing machine. Take lukewarm shower, with soap. And hope, you didn’t get it :grin:.


I’ve never heard of or experienced Roundup not working. It may take one to two weeks. Perhaps concentration was too weak or coverage was not complete.


Yes what richard said. Sold commercially as Crossbow. You can purchase the knockoff (crossroads) at Rural king for about 1/5th the cost.


Out here in California we have poison oak. I know it’s more irritating/sickening, but I’m not sure if it’s more/less tenacious than poison ivy. Roundup Toughbrush works very well, but regular roundup is pretty ineffective. The Toughbrush label says it’s for poison oak and ivy, not sure if it’s necessary for ivy though. Works pretty well on poison oak, although you have to get it early when it comes out in spring and takes multiple applications to be very effective.


I have indeed experienced many shrubs and brush species laughing at glyphosate. Even at much higher than recommended application rates. Using gly to kill PI is an exercise in futility. It may burn the stuff to the ground, but it will come back from the roots.

I use Crossbow on tough to kill brushy species. I also have used straight triclopyr. Both work very well


smsmith -

I applied it almost full strength. It wilted, looked dead and burnt. 3 weeks later when i checked it was like i never was there at all. Unbelievable.

Thanks. Will try the triclopyr and cover kill. Will tell my neighbor to try it on his side as hes had the same problem.


Stuff makes me so sick. I hate it.
Good removal advice ty


Never tried Toughbrush.
Maybe some of this crap is resistant. I dunno. I feel crazy trying escalating so many times to try to kill this.




What i thought too. I dont like roundup, never needed it. Felt bad using it at such high strength and then to still be messing with the PI after 3 sprays … :astonished:


Roundup Tough Brush simply has some added triclopyr


smsmith (i keep hitting the wrong reply button!!!)

Ok. Im going to use it. Cover it all with layers of cardboard and fabric and maybe over-plant it in a few years :+1:


Stay on top of the PI. I have eliminated a LOT of it here, but thanks to nobody else in the area trying to control the stuff it keeps showing up. Birds and mammals actually use PI foliage and fruits for food. PI shows up on my fence lines most every year…I imagine thanks to birds pooping out seeds. My wife and step-kids get severe reactions to the stuff and no matter how many times I’ve showed it to them…they continue to struggle with consistently IDing the stuff. I persecute PI with extreme prejudice


Yr poor family. I get that totally ive ended up with steroids and even inhalers bc of it.
‘Extreme prejuduce’
That is exactly how to go.


Consensus is triclopyr. TY


My best tool for fighting ivy is the lawnmower. In my experience ivy hates to be mowed, and doing so regularly will chase it out of an area reasonably quickly. A weedeater will do the same as long as you get all the leaves.


I’ve had success with Triclopyr against PI as well. Crossbow is a mix of 2, 4-D and Triclopyr. I use Bayer Advanced Brush Killer Plus which only has Triclopyr as it’s active ingredient.


Thanks, I couldn’t remember what the additive was.